OF THE EPA ALSEA II
STUDY AND REPORT
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ENVIRONMENTAL HEALTH SCIENCES CENTER
OCTOBER 25, 1979
A SCIENTIFIC CRITIQUE OF THE EPA ALSEA II
STUDY AND REPORT
Sheldon
Sheldon L.
L. Wagner,
Wagner, M.D.
M.D.
Research Professor, Environmental Health Sciences Center
Oregon State University, Corvallis
James
James M.
N. Witt, Ph.D.
Professor, Department of Agricultural Chemistry
Oregon State University,
University, Corvallis
Corvallis
Logan A. Norris, Ph.D.
Supervisory Research Chemist
Pacific Northwest Forest and Range Experiment Station
USDA Forest Service, Corvallis
James E. Higgins, Ph.D.
Assistant Professor, Department of Epidemiology and Statistics
University of South Carolina, Columbia
Alan Agresti, Ph.D.
Associate Professor,
Professor, Department
Department of
of Statistics
Statistics
University of Florida, Gainesville
and Visting Associate Professor, Department of Statistics
Oregon State
State University,
University, Corvallis
Corvallis
Oregon
Meichoir Ortiz, Jr.,
Melchoir
Jr., Ph.D.
Ph.D.
Assistant Professor, Department of Experimental Statistics
New Mexico State University,
University, Las
Las Cruces
Cruces
October 25, 1979
ENVIRONMENTAL HEALTH SCIENCES CENTER
Oregon State University
Corvallis
FORWARD
Health is a very precious possession of the human.
It should not be
needlessly jeopardized but rather protected by every rational means.
Increasingly, we have been concerned with chronic effects produced by
environmental agents - physical, biological, and chemical.
In recent
years, much attention has been focused on chemical agents in the
environment, particularly
particularly the
the man-made
man-made chemicals
chemicals that,
that, by
by one
one means
means or
or
another, find their way into the environment.
The Environmental Health
Sciences Center at Oregon State University, established over a decade
ago, has as its primary mission the study of the toxicology of
environmental chemicals in order to assess possible hazards and provide
a basis for developing strategies to prevent these hazards.
The Center,
supported by Oregon State University and grants from the National
Institute of Health, pursues this mission through research, training,
and a number of other activities.
From
From time
time to
to time,
time, special
special problems
problems
arise calling for study and evaluation by interdisciplinary task forces.
Such task forces bring their expertise to bear on the problem of
collecting and analyzing the relevant information and then preparing a
report for public use.
For some years, the use of the herbicide 2,4,5-T has been under serious
challenge by some segments of the public and the scientific community.
Many studies using laboratory animals and doses above that experienced
in
in the
the environment
environment have
have been
been carried
carried out
out on
on the
the toxicology
toxicology of
of 2,4,5-T
2,4,5-T
and its low level contaminant, TCDD.
However, some
some individuals
individuals have
have
However,
claimed to have suffered ill effects from exposure to 2,4,5-T in the
environment.
One such claim involving spontaneous abortions resulted in
the Environmental Protection Agency "Alsea II Study."
The results of
this study played a prominent role in the Agency's decision to suspend
the use of 2,4,5-T in forestry.
AA number
number of
of individual
individual scientists
scientists and
and groups,
groups, not
not only
only in
in this
this country
country
but in other countries as well, challenge the study and its conclusion.
Consequently, because of this sharp difference of opinion and the
familiarity of staff
staff members
members and
and associated
associated investigators
investigators of
of the
the
Environmental Health Sciences Center with the area and the problem, it
was felt that the Center should undertake its own independent study.
Accordingly, an interdisciplinary task force to study this problem was
formed.
It was composed of Sheldon L. Wagner, M.D. (toxicologist);
James M. Witt, Ph.D. (environmental toxicologist/hazard assessment);
Logan A. Norris, Ph.D. (environmental chemist/forestry); James E.
Higgins, Ph.D. (statistician); Alan Agresti, Ph.D. (statistician); and
Melchoir Ortiz, Jr., Ph.D. (statistician).
After detailed study,
consultation with many colleagues and the development of new
information, this task force prepared the following report.
We believe
that it adds substantive new information that would be of wide interest
of those concerned with the problem.
V. H. Freed, Ph.D.
Director, Environmental Health
Sciences Center
Oregon State University
11
TABLE OF CONTENTS
SUMMARY............................................................
STJMNARY............................................................
INTRODUCTION .......................................................
.......................................................
PART 1.
THE
THE DEVELOPMENT
DEVELOPMENT AND
AND COMPARISON
COMPARISON OF
OF THE
THE HOSPITALIZED
HOSPITALIZED
SPONTANEOUS ABORTION INDICES .......................................
DESCRIPTION OF THE THREE AREAS INCLUDED IN THE ALSEA II
STUDY.........................................................
Description of the
the Study
Study Area
Area ............................
............................
Description of the
the Control
Control Area
Area ..........................
..........................
Description of the Urban Area ............................ 10
Comparisons Among the Three Areas ........................ 13
THE HOSPITALIZED SPONTANEOUS ABORTION (HSAb) DATA BASE ........ 14
The Hospitalized Spontaneous Abortion Index (HSAI) ....... 15
Medical Practice Profile ................................. 16
Physician
Physician Distribution ..............................
.............................. 16
16
Hospitalization Rate for HSAb Patients .............. 17
TheStudy
The
Study Area
Area .................................
................................. 17
The Urban Area
Area .................................
................................. 18
TheUrban
The Control Area ............................... 19
COMPARISON OF HSAb, HSAI DATA ANONG
AMONG AREAS ..................... 20
PART 2.
SEASONAL
SEASONAL CYCLIC
CYCLIC PEAKS
PEAKS IN
IN THE
THE HSAI
HSAI .........................
......................... 25
25
CYCLIC PEAKS .................................................. 25
THE JUNE PEAK ................................................. 27
PART 3.
RELATION BETWEEN HSAI
HSAI AND
AND 2,4,5-T
2,4,5-T USE
USE IN
IN THE
THE STUDY
STUDY AREA...
AREA
31
31
LENGTH
LENGTH OF
OF GESTATION
GESTATION ...........................................
........................................... 31
31
2,4,5-T SPRAY DATA
DATA ............................................
............................................ 32
THE HSAI VERSUS 2,4,5-T SPRAY DATA ............................ 35
POTENTIAL
POTENTIAL FOR
FOR HUMAN
HUMAN EXPOSURE
EXPOSURE ..................................
.................................. 39
39
CONCLUSIONS ........................................................ 43
APPENDIX 1 - Population Statistics .................................
................................. 47
47
APPENDIX 2 - Hospitalized Spontaneous Abortion Statistics .......... 53
APPENDIX 3 - 2,4,5-T
2,4,5-T Use
Use Statistics
Statistics ................................
................................ 75
75
iii
A SCIENTIFIC CRITIQUE OF THE EPA ALSEA II
REPORT-i'
STUDY AND REPORT-'
by
Sheldon L. Wagner, James M. Witt, Logan A. Norris
James E. Higgins, Alan Agresti, and Melchoir
Meichoir Ortiz, Jr.
SUMMARY
In 1978, women living near Alsea, Oregon, a forested area in which
2,4,5trichlorophenoxyacetic acid (2,4,5T) is used seasonally, noted an
2,4,5trichiorophenoxyacetic
apparent temporal relationship between their spontaneous abortions and
the use of this herbicide on adjacent land.
A twopart investigation of
this incident was conducted by the U.S. Environmental Protection Agency
(EPA).
The first part (Alsea I) did not find a relationship between
spraying and abortions.
In the second part (Alsea II) EPA reported (a)
the abortion rate was higher in the Study area than in either the
Control or Urban area (b) there was a seasonal fourmonth cycle of
-
(c)
abortions with an outstanding peak in June in the Study area and (c)
there is a significant crosscorrelation between the spontaneous
abortion index and the pattern of 2,4,5T use in the Study area.
Our
Aisea
critique does not support any of the three conclusions from EPA's Alsea
II study.
This critique shdws that EPA reached erroneous conclusions from the
Alsea
Alsea II study because of:
(1) failure to account for differences in the
characteristics between the Study area and the Rural and Urban control
spontaneous
data on
on spontaneous
areas, (2) inaccuracies in the collection of data
abortions, (3) failure to account for marked differences in the medical
data on
on 2,4,5T
2,4,5T
practice among areas, (4) incomplete and inaccurate data
magnitude of the monthly
monthly
use,
use, and
and (5)
(5) failure
failure to
to recognize
recognize that
that the
the magnitude
contributions by
by Scott
Scott Overton,
Overton, Ph.D.,
Ph.D., Professor,
Professor, Department
Department
'Inc1udes contributions
!"Includes
of Statistics, Oregon State University, Corvallis, Oregon.
variations in rates of hospitalized spontaneous abortions (HSAb) in all
three areas is no greater than would be expected due to random
variations.
When corrections for some of these problems are applied, we
find the rate of spontaneous abortions in the Study area
area does
does not
not appear
appear
to be related to the use of 2,4,5T.
Retrospective studies
studies such
such as
as the
the Alsea
Alsea II
II study
study are
are exceedingly
exceedingly
difficult to conduct.
The net effect of attempting a comparison among
several poorly identified populations is to obscure the potentially
significant data by the mass of other data containing no information.
When poorly done, these studies confuse rather than clarify issues,
Issues, in
this case the risks from using agricultural chemicals in our country.
The original contention of the women from Alsea,
Aisea, Oregon, namely that
there is a relationship between herbicide use and miscarriages, is not
supported by the data in EPA's Alsea II Report.
INTRODUCTION
Controversy, both technical and philosophical, has surrounded the use of
2,4,5T in
in forestry
forestry since
since the
the late
late 1960's.
196Os.
It was
was heightened
heightened by
by (1)
(I) the
the
It
use of
of "Agent
"Agent Orange"
Orange" (a
(a herbicide
herbicide formulation
formulation containing
containing 2,4,5T) in
use
Vietnam and (2) the discovery that 2,4,5T contained the highly toxic
trace contaminant, 2,3,7,8tetrachlorodibenzopdioxin (TCDD).
In 1978,
EPA issued a Rebuttable Presumption Against Registration of 2,4,5T as
provided for in the Federal Insecticide, Fungicide, and Rodenticide Act
as amended.
EPA stated that pesticide products containing 2,4,5T
and/or TCDD could produce oncogenic or other toxic effects (including
reproductive effects) in laboratory species and therefore presumably
could do so in humans.
humans.
In July, 1978, EPA began an investigation into a possible cause/effect
relationship between spontaneous abortions in humans and the use of
2,4,5T on forests
forests in
in the
the Alsea
Alsea area
area of
of western
western Oregon.
Oregon.
The
investigation was precipitated by a letter signed by eight women living
in the area who felt there was a temporal relationship between
miscarriages and forest spraying between May 1973 and March 1978.
The
The
investigation was conducted by the EPA Office of Pesticide Programs,
Benefits and Field Studies Division, Human Effects Monitoring Branch,
Epidemiologic Studies Program.
It was divided into two phases.
The first phase, called Alsea I, was conducted by (1)
(I) having the women
who raised the issue complete a lengthy health questionnaire, (2)
determining the amount and timing of 2,4,5T use in the 400 squaremile
Alsea Basin, and (3) having the data reviewed by 10 Universitybased
obstetricians and/or clinical epidemiologists.
The reviewers
unanimously concluded there was no cause/effect relationship between the
miscarriages noted by the women and the use of 2,4,5T and "that there
was no real evidence of an epidemic based on the data presented."
Several, however, commented that most of the abortions in this sample
occurred in the spring, and EPA staff noted a possible temporal
relationship between the miscarriages described by these women and the
application of 2,4,5T in the spring.
P
The second phase, called Alsea II, was initiated in October 1978.
It
was to investigate the possible relationship between spontaneous
abortions within the first 20 weeks of gestation and the use of 2,4,5T
over a substantially larger geographic area and population base than
that included in the Alsea I study.
The Alsea II study is an observationalretrospective study of
spontaneous abortions and the use of 2,4,5T in forest spraying.
Most
ecological and sociological data come from observational studies, in
which experimental controls cannot be exercised.
The mechanics of
analysis of such data may be the same as that of formal experiments, but
the inferences are substantially different, as are many of the
associated methods and protocol.
For example, associations may be
proven from observational data, but causality of an observed association
may be inferred only by assumption.
In such cases all possible
alternate explanations of the association must be examined.
If they can
be rejected the explanation by causality is more tenable, but it stil.l
is not proven.
It is proper to use observational, studies to pose
hypotheses, and to express the results only in terms of the identified
associations.
Retrospective studies require a greater subjective element in the
analysis and greater ingenuity and insight on the part of the
investigator.
Analysis of experimental, data is dictated by the design
of the experiment; analysis of data from retrospective studies is guided
by the perspective of the system being studied.
Review and interaction
with peers is an important part of observational studies.
The Alsea II
study suffers serious shortcomings in both these regards.
Alsea II is not only a retrospective study, it is comparative in that
data on spontaneous abortions in one area were compared with similar
data from other areas.
A basic assumption in any comparative study is
that those data being compared are either comparable directly or are
adjusted on
on aa rational,
rational basis
basis to
to make
make them
them comparable.
Three kinds of
data were collected by EPA for use in the Alsea II study.
They are:
1.
HospItalized spontaneous abortions following no more than 20
Hospitalized
weeks of gestation.
2.
Live
Live births occurring in the same area.
area.
3.
The timing and magnitude of the use of 2,4,5T in the Alsea
Aisea
Basin
Basin portion
portion of
of the
the Study
Study area.
area.
uses of
of each
each of
of these
these data
data and
and how
how they
they were
were analyzed
analyzed
The sources and uses
are examined in later parts of this critique.
The Alsea II study covered the time period 1972-1977, and an area of
approximately
approxImately 1600
1600 square
square miles
miles including
including all
all of
of the
the area
area in
in the
the Alsea
Alsea II
study.
This was called the Study area.
area were also included for comparison.
A rural Control and an Urban
At the conclusion
conclusion of
of the
the Alsea
Alsea
II study, the results were given in "Report of Assessment of a Field
Investigation of SixYear Spontaneous Abortion Rates in Three Oregon
Areas in Relation to Forest 2,4,5T Spray Practices" dated February 27,
1979 (Alsea II Report).
1.
I.
In this report, EPA concluded:
The 1972-1977 abortion rate index was significantly higher in
In
the Alsea II Study area than in either a rural Control or a
nearby
nearby Urban area.
2.
There was a statistically significant seasonal cycle in the
abortion index in each of the areas with a period of about 4
months.
In particular, there was an outstanding peak in June
in the Study area.
3.
There was a statistically significant crosscorrelation
between the spontaneous abortion index in the Study area and
the pounds of 2,4,5T applied by months in the Alsea basin,
1972-1977, after aa lag
lag time
time of
of two
two to
to three
three months.
months.
The results of the Alsea II study added substantially to the controversy
regarding the use of 2,4,5T in forestry.
It was an important factor in
the EPA decision to issue an emergency suspension of the uses of
2,4,5T in forests, pastures, and rightsofway in the United States.
The purpose of this critique is to examine the methods, data,
assumptions, and analysis of the data in the Alsea II Report to
determine if there is an adequate basis for the conclusions reported by
EPA.
This critique has three major parts, one for each of the EPA
conclusions:
Part 1 reviews the areas studied and the hospitalized spontaneous
abortion indices (HSAI)
(HSAI) to
to determine
determine if
if differences
differences in
in the
the indices
indices
among geographic areas can be detected based on the methods and
data in the study.
study.
Part 2 examines the HSAI for the various areas for cyclic trends
with particular attention to the reported June peak in the Study
area.
Part 3 examines the pattern of 2,4,5T use in the Study area to
determine if there is a relationship between either the amount or
timing of
timing
of the
the use
use of
of 2,4,5.-T
2,4,5T and
and the
the HSAI
HSAI in
in the
the Study area.
area.
Appendices which include both basic data and data analysis are provided
for the reader who
who wishes
wishes to
to pursue
pursue certain
certain aspects
aspects of
of this
this critique
critique in
in
more detail.
These appendices include the basic data collected by EPA
on hospitalized spontaneous abortions (HSAb) by month and year for each
area.
These data were not included in the Alsea II Report, but are
essential for the reader wishing to independently evaluate the EPA
conclusions.
We also include more accurate and more complete
demographic and 2,4,5T use data than that reported by EPA in the Alsea
II Report.
For the convenience of readers wishing to carry out
independent data analyses involving the abortion rate, we have included
the necessary EPA data on live births from the Alsea II report.
Since
this data was inaccurate, we have also included live birth data collected
by EPA after the Alsea II Report was prepared.
PART 1.
THE DEVELOPMENT AND COMPARISON OF THE HOSPITALIZED
ThE
SPONTANEOUS
SPONTANEOUS ABORTION
ABORTION INDICES
INDICES
DESCRIPTIONS OF THE THREE AREAS INCLUDED IN THE ALSEA II STUDY
The study was conducted in three areas identified as the Study area, the
EPA concluded that
that the
the Study
Study area
area and
and
Control area, and the Urban area.
the Control
Control area
area were
were similiar.
similiar.
the
They included an Urban area as an
additional unit for comparison.
The Urban area was not specified as a
control, but it was utilized for that purpose.
DESCRIPTION OF STUDY AREA
The Study area in Alsea II was intended to represent an enlarged version
of the Alsea I study area.
It includes 1600 square miles of mostly
20
deeply dissected, heavily forested, mountain land which encompasses 20
postal zip code areas
areas (Figure
(Figure 1).
1).
included.
All of the Alsea I study area is
The
The western
western boundary
boundary is
is the
the Pacific
Pacific Ocean.
Ocean.
The terrain
level, however, humans live
ranges
ranges up
up to
to more
more than
than 4037
4037 feet
feet above
above sea
sea level,
almost exclusively along the coast or in canyon bottoms along streams at
elevations of less than 750 feet.
Climatologically the study area is cool and moist with a mean annual
high and low temperature of 49°F and 36°F for January and 66°F and 51°F
for July.
The
The mean annual precipitation is 75
75 inches.
inches.
Most of the
precipitation falls as rain between October and May.
The image of homesteads scattered through the Study area conveyed to
some
some by
by the
the Alsea
Alsea II
II Report
Report is
is misleading.
misleading.
Although the Alsea
Alsea II
II
Report characterized the Study area as "predominantly rural," the
population
population data
data we
we assembled
assembled reveal
reveal aa different
different picture
picture (Appendix
(Appendix I,
I,
Tables 1 and 2).
The Study area was characterized by EPA as containing
16,150
16,150 persons
persons in
in urban
urban settings.
settings.
More accurate population estimates
in rural
19,000 in
show that there are 34,000 persons in urban settings and 19,000
settings in the Study area.
The
The human
human population
population in
in the
the Study
Study area
area is
is
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area.
Figure 1--The
1--The Study
Study area.
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qT3Gb
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STUDY /IPE/
Figure 2--The
Figure
2--The Control
Control area.
area.
AL51A II STUOT
AL51*
RURAL
CONTROL AREA
concentrated in four urban centers (Florence, Waldport, Newport, and
Lincoln City) which front on the Pacific Ocean.
Residents served by
by the
the
four zip codes of these coastal communities account for 2/3 of the
population of the Study area.
The coastal population predominates over
the inland population
population (35,000
(35,000 to
to 18,000).
18,000).
In terms of population (but
the Study
Study area
area should
should be characterized as an
not
geography),
not geography)
, the
urban/coastal area rather than a rural/forest area.
The
The potential
potential for
for
exposure of coastal residents to 2,4,5T from forest spraying is
substantially different than for individuals living in the heavily
forested,
forested, interior
interior portions
portions of
of the
the Study
Study area.
area.
Business in the coastal area is concentrated in tourism and fishing
rather than forestry.
Because of tourism, the population of the coastal
portion of the Study area increases (at least doubles) during the summer
months.
DESCRIPTION OF THE CONTROL AREA
The Control area is
Is located in Malheur County, adjacent to the Idaho
Oregon border, approximately 400 miles east of the Study area (Figure
2).
The EPA described the Control area
area as
as being
being topographically
topographically similar
similar
to the Study area,
area, being
being of
of similar
similar elevation
elevation and,
and, although
although not
not
rolling
mountainous, having
having rugged
rugged terrain
terrain comprised
comprised of
of escarpments,
escarpments, rolling
hills, arroyos, and canyons; covering approximately 1,000 square miles
and consisting of 90% rangeland and sagebrush; cropland accounts for a
small but important
important percentage
percentage of
of the
the area
area along
along stream
stream and
and river
river
courses.
The
The EPA
EPA description
description is
Is reasonably
reasonably accurate
accurate for
for Malheur
Malheur County
County
as a whole, but it is not accurate for the area designated as the rural
ContrQl area (the area served by zip codes 97914, 97913, 97918, 97906).
Control
The Control area is, in fact, that portion described by EPA as a small
but important
Important area of cropland along stream and river courses.
The
The
control area
area is
is flat,
flat, intensively
intensively cultivated,
cultivated, lies
lies along
along the
the Malheur,
Malheur,
control
Owyhee, or Snake Rivers,
RIvers, consists of about 350 square miles, and is
about 85% cultivated land.
Only
Only incidental
incidental amounts
amounts of
of escarpments,
escarpments,
code zones.
arroyos, and sagebrush are included in the zip code
The
The zip code
zones include homes receiving mail service, and there are very few, if
any, homes outside the area of irrigated cropland.
Domestic water
supplies are lacking on the rugged, sagebrush covered land adjacent to
the cultivated, irrigated areas.
feet.
feet.
Elevations range from 2,100 to 2,500
The area has cold dry winters, and hot dry summers.
The mean
high and low temperatures are 36°F and 19°F in January and 92°F and 57°F
in July.
Mean annual precipitation is 10 inches.
The human population in the Control area was characterized in the Alsea
II Report as 13,000 persons in three urban centers.
No figures were
given for the rural population, even though one of the reasons
reasons EPA
EPA
selected this area as the Control area was that they believed it was primarily
rural.
Our estimate is that there are 16,500 persons living in urban
settings and 6,000 in rural settings (Appendix I, Tables 1
I and 3).
DESCRIPTION OF THE URBAN AREA
The Urban area is adjacent to the eastern boundary of the Study area
(Figure 3).
The mean high and low temperatures are 45°F and 34°F in
January and 82°F and 52°F in July.
inches.
Mean annual precipitation is 40
It includes the city of Corvallis and adjacent areas in zip
code 97330 which is largely in Benton County, but includes as
as well
well aa
small part of Linn County.
code 97321 (Albany).
The Urban area also includes some of zip
How much of 97321 is included is not known.
The
map of the Urban area in the Alsea II Report appears to include only
those parts of zip codes 97321 and 97330 which are in Benton County.
This would include North Albany, a small unincorporated suburb of Albany
in Benton County but would exclude all of the city of Albany and that
that
portion of zip code 97330 in Linn County.
Only data from Good Samaritan Hospital in Corvallis were used for the
Urban area.
Almost all residents of 97330 would use this hospital, but
only a few individuals from 97321 would be included because most would
use the Albany General Hospital which was not included in the study.
The use of a small but unidentified segment of the population from zip
zip
10
11
code area 97321 (Albany) has the result of making it impossible to
accurately define the Urban area either demographically or
geographically (and provides no apparent benefit in the collection of
the HSAb data).
The
The Alsea
Alsea II
II study
study also
also appears
appears to
to have
have excluded
excluded Oregon
Oregon State
State University
University
students
students housed
housed in
in dormitories
dormitories which
which use
use zip
zip code
code 97332
97332 in
in Corvallis.
Corvallis.
The exclusion of this zip code may not be significant, however, since
the Medical Records Department at Good Samaritan Hospital also ignores
that zip code and uses 97330 for all, patients with an address in the
ci-ty of
city
of Corvallis.
Corvallis.
The impact of Oregon
Oregon State
State University
University upon
upon the
the Urban
Urban area
area was
was not
not
discussed (and presumably, therefore, not considered) in the Alsea II
Report.
Population levels of both students and townspeople fluctuate
considerably during
considerably
during the
the year,
year, with
with aa substantial
substantialdecrease
decreaseininthe
thesumnier
summer
months.
&ur population estimates (Appendix I, Tables I and 3) for the Urban area
Our
area
show
show 46,310
46,310 persons
persons in
in urban
urban settings
settings and
and 5,229
5,229 persons
persons (lI7)
(lI7) in
in rural
rural
settings in zip code 97330 (Corvallis).
Our figure for the Urban area
is too small because
because the
the persons
persons from
from Albany
Albany zip
zip code
code 97321
97321 using
using the
the
Corvallis hospital represent an unknown proportion of that population.
On the other hand, a sum of the Corvallis and Albany populations would
exaggerate the size of the Urban area population.
This make it
impossible to precise1y
precisely define the size of the population of the Urban
area.
In contrast to the impression conveyed by the Alsea II Report,
the population
population of
of the
the Study
Study area
area (53,463)
(53,463) is
is about
about the
the same
the
same as for the
Urban area (51,539, urban and rural components of Corvallis population
only).
According to the Alsea II Report, the investigators recognized at least
some facets of the limited utility of the data collected from the Urban
area.
However, these limitations were disregarded in the analysis and
discussion of the data, and in some cases data from the Urban and
12
Control areas were combined in making comparisons with data from the
Study area.
COMPARISONS A1{ONG
AJ(ONG THE THREE AREAS
In considering the three areas included in the Alsea II study, we
find
substantive differences in their climatic, topographic, demographic,
ethnic, and economic factors, and their cultural, industrial, and
agricultural practices.
We believe these factors were not considered as
important in the Alsea II Report because they were not discussed.
These factors are important because they influence the character of the
human populations examined.
Neither the Study nor the Control areas
have predominantly rural populations as described by the Alsea II
Report.
Report.
More importantly, their rural components are not comparable.
The principal valid point noted by EPA is that little or no 2,4,5T was
used in the Control area between 1972 and 1977.
in
We believe there are real differences in life styles, particularly in
the rural populations,
populations, among
among areas.
areas.
These may be reflected in different
attitudes,
attitudes, social
social mores,
mores, food
food usage,
usage, shelter,
shelter, and
and living
living conditions.
conditions.
These differences are likely to affect reproductive success and could
result in misleading conclusions about these populations from the study
of reproductive statistics.
THE HOSPITALIZED SPONTANEOUS ABORTION (HSAb) DATA BASE
The true number of spontaneous abortions in a large human population is
difficult to determine because many are not detected medically and
others are handled in outpatient facilities where records are less
easily retrievable.
The data on hospitalized spontaneous abortions were
collected only from inpatient records in seven hospitals, four in the
Study area, two in the Control area, and one in the Urban area.
Patients
were assigned to a particular area based on the zip code of their residence,
not the hospital in which they were treated.
Thus, data on patients
from the Study area who were treated in the Urban area hospital by Urban
area physicians were, in fact, included in the Study area data base.
Statistics on spontaneous abortions from different areas or time periods
are difficult to compare because the number of abortions which occur and
which are reported vary with the level of medical practice for the area,
the number of pregnancies, and a wide range of social, economic, and
biologic factors.
The ages of the patients included in the study
illustrate the variability of some of these factors.
Table 8 of the Alsea II Report lists hospitalized spontaneous abortion
cases for the Study, Urban, and Control areas by the age groups of the
patients.
There is a disproportionate number of spontaneous abortion
cases occurring in the Study area for patients in the age group of
10-19 years.
This age group of patients constitute 21.8%, 6.7%, and
12.8% of all patients from the Study, Urban, and Control areas,
respectively.
This difference in age groups is not accounted for in the
analyses which compare the data from the three areas.
If there is a
larger number of individuals in the young age group in the study area,
then an elevation of the HSAI in the Study area would have greater
meaning than a similar increase in the Urban or Control areas because a
younger age group should have fewer abortions.
The relatively large number of 10 to 19year old mothers in the Study
area may also reflect different cultural mores or socioeconomic
factors, e.g., the population in the Study area may tend to marry at a
14
younger age.
The marriage rate may increase during the early summer
months following high school graduation.
Residents in the Study area
have a lower average income compared to the Urban area in particular.
socloeconomic groups have higher rates of spontaneous abortion.
Lower socioeconomic
This variable, and other factors needing study, may be important.
THE HOSPITALIZED SPONTANEOUS
ABORTIONINDEX
INDEX (HSAI)
(HSAI)
SPONTANEOUS ABORTION
EPA devised a Hospitalized Spontaneous Abortion Index (HSAI) as a
relative measure of the spontaneous abortions which occurred in each of
the three areas included in this study.
This index is the ratio of the
number of hospitalized spontaneous abortions (HSAb) to the weighted
average of the number of live births, multiplied by 1,000 (HSAb is
defined by EPA as
as occurring
occurring at
at less
less than
than 20
20 weeks
weeks gestation,
gestation, but
but it
it
appears that in the study the 20th week was included).
More
specifically:
1.
1.
The numerator
nwnerator is the number of hospitalized spontaneous abortions
of 20 weeks gestation or less from a particular area (based on
patient
patient zip codes).
The data was collected only from patient
records from each of the seven hospitals in the study for each
month during the years 1972 through 1977.
Data
Data on
on spontaneous
spontaneous
abortion
abortion patients
patients treated
treated in
in hospital
hospital emergency
emergency rooms,
rooms, clinics,
clinics, or
or
physician offices were excluded from the study.
The single
exception
exception was
was the
the emergency
emergency room
room records
records from
from the
the Toledo,
Toledo, Oregon,
Oregon,
hospital.
Here,
Here, both
both outpatient
outpatient and
and inpatient
inpatient records
records were
were
included.
included.
2.
The denominator is a fivemonth movingaverage of the live births
derived from Oregon State Health Division vital
vita' statistics and
birth
birth data
data for
for what
what was
was believed
believed to
to be
be the
the same
same area
area and
and period
period of
of
time.
Knowing the source and meaning of the data used for calculating the HSAI
is extremely important in determining if the comparisons EPA attempted
15
It appears the number of
in the Alsea II Report can logically be made.
HSAb's were counted correctly, but they were not adjusted for
differences in medical practice among areas.
in the Alsea II Report is
Is incorrect.
The live birth data used
We have included the live birth
data used in the Alsea II Report and an example of a set of corrected
data compiled by EPA after the Alsea II Report was released (Appendix 2,
Tables Ia, ib, and
and 2).
2).
MEDICAL PRACTICE PROFILE
In order to conduct an epidemiological study of hospitalized spontaneous
abortions it is necessary to consider variations in medical practice
within each area if comparisons among areas are to be made.
Some differences
were recognized by EPA investigators, several others were not.
Errors
associated with erroneous assumptions and unperceived differences in
medical practice seriously complicate both the data and their analysis.
Physician Distribution
The Aisea
Alsea II report
report infers
infers the
the populations
populations of
of each
each area
area are
are served
served
exclusively or largely by physicians that practice within that area.
A
medical profile of the Urban and Study areas performed in 1974 by the
Comprehensive Health Planning Agency (now Western Oregon Health Systems
Agency), Oregon
Oregon District
District 4,
4, shows
shows this
this was
was not
not the
the case.
case.
Agency),
The latter
report demonstrated that 50% of all obstetrical care in western Benton
County and in Lincoln County was performed by physicians in the Urban
area, i.e., Corvallis.
Corvallis.
According to the Alsea II Report, EPA assumed that the medical care in
the Control and Study areas were essentially identical.
This assumption
is based on the investigators understanding that 'both areas are
predominantly rural and therefore similar.
In fact, neither area
area is
is
predominantly rural in terms of the human population studied.
16
16
The Study area has a shortage of physicians.
The western part of
Benton County was an area of physician shortage, and two physicians
began practicing there after 1977 under the National Health Services
Act.
In the remainder of the Study area, there are a total of 39
physicians, including both general practitioners and specialists.
In
the Control area, by contrast, the Oregon Medical Association Directory
lists a total of 60
60 physicians.
physicians.
Based on Census Bureau statistics,
there are substantially fewer doctors in the Study area (1
(I doctor per
1,370 persons) than in the Contro1
Control area (I doctor per 378 persons) on a
per capita basis.
This apparent shortage of doctors is less real than
the physician per capita analysis suggests because a high percentage of
the medical care in the Study area is delivered in the Urban area.
Nevertheless, a substantially different level of medical care is
delivered in
In these two areas, a factor likely to influence the level of
prenatal care and the number of spontaneous abortion patients
hospitalized,
hospitalized, and,
and, therefore,
therefore, the
the number
number counted
counted in
in this
this study.
study.
Hospitalization Rate for HSAb Patients
Hospital records account for only a portion of the spontaneous abortion
patients seen by physicians.
EPA used physician interviews to estimate
the proportion of spontaneous abortion patients that are hospitalized
and would therefore be counted in the Alsea II study.
We have not been
able to corroborate the results of the EPA physician interviews and
believe they
they are
are in
in substantial
substantial error.
error.
believe
The Study Area
The Alsea II Report states "in the study area, 19 of 27 (70%) of the
physicians--all general practitioners--were contacted."
are only 17 general practitioners in the Study area.
In fact, there
We contacted nine
of
of them,
them, all
all of
of whom
whom have
have now,
now, or
or have
have had
had in
in the
the past,
past, aa large
large
obstetrical practice.
practice.
with EPA investigators.
Only four recall an interview (one via telephone)
The interviews must have been brief, and it is
likely the physicians did not understand and study fully the questions
put to them.
17
Based upon these interviews, EPA reached the conclusion that the medical
practice profile in
in the
the Study
Study area
area would
would be
be to
to hospitalize
hospitalize 70%
70% of
of
patients who are undergoing a spontaneous abortion.
Of the nine general
practitioners we contacted in the Study area, only three estimated that
they hospitalize 70% of all spontaneous abortion patients; the
hospitalization rate estimated by six others ranges from 25 to 50%.
The hospitalization rate of spontaneous abortion patients from the Study
area is further confounded because, as noted earlier, physicians,
principally the practicing obstetricians, in the Urban area handled 50%
of the obstetrical care for the Study area during the study period.
This would likely
likely include
include those
those same
same patients
patients undergoing
undergoing aa spontaneous
spontaneous
abortion as well.
The obstetricians in the Urban area estimate only a
10% hospitalization
hospitalization rate
rate because
because the
the majority
majority of
of this
this medical
medical practice
practice
is handled in the
the Good
Good Samaritan
Samaritan Hospital
Hospital emergency
emergency room
room or
or the
the
physician's office.
Thus, 90% of these abortions would not be counted
in the EPA study.
study.
The incompleteness of the HSAb data base for the Study area is
illustrated
illustrated by
by comparing
comparing the
the Alsea
Alsea II and
and Alsea
Alsea II
II studies.
studies.
The Alsea I
study dealt with 13 medically confirmed abortions, Il
11 of which occurred
within the first 20 weeks of gestation in the years covered by the Alsea
II Report.
Of these 11, only 3 appeared in the hospital records used in
the Alsea II study.
The assumed hospitalization
hospitalization rate
rate of
of 70%
70% for
for
spontaneous abortion patients from the Study area (as indicated in the
Alsea II Report) is substantially incorrect.
The Urban Area
In the Urban area, the Alsea II Report estimates 30% of all spontaneous
abortion patients were hospitalized.
This is based on the assumption
that 70% of all spontaneous abortions seen by general practitioners are
hospitalized while 10% of the cases seen by obstetricians are
hospitalized.
The estimated 70%
70% hospitalization
hospitalization rate
rate for
for cases
cases seen
seen by
by
general practitioners was (according to the Alsea II Report) based on
is
interviews with five general practitioners out of what EPA believed to
be a total population of 24 general practitioners.
During the study
period, the number of general practitioners in the Urban area ranged
between five and eight people, not all of whom had an obstetrics
practice.
There were only six fulltime general practitioners, only one
of whom engaged in the practice of obstetrics in the Urban area at the
time of the investigation.
EPA's assumption of 24 fulltime general
practitioners in the Urban area, all of whom practice obstetrics, introduces
30% hospitalization
an important error into the weighted estimate of 30%
rate for the Urban area that they derived.
We contacted every general practitioner in the Corvallis portion of the
Urban area regarding the EPA interviews.
Only one recalled any type of
interview with investigators from the EPA team.
This particular
physician does not have an obstetrics practice.
In our interview, the
one general practitioner in Corvallis with a large obstetrics practice
estimated 25% of the spontaneous abortion patients he sees are actually
hospitalized.
The hospitalization rate of 30% for spontaneous abortion
patients from the Urban area is substantially incorrect.
The Control Area
The EPA investigators made an assumption that medical practice in the
Control area was similiar to the Study area.
all were conducted by EPA.
No physician interviews at
We contacted three physicians who have a
large obstetrics practice in the Control area.
One estimated 70% of all
spontaneous abortion patients are hospitalized, the other two estimated
a 50% hospitalization rate.
19
COMPARISON OF HSAb AND HSAI DATA AMONG AREAS
The Alsea II Report showed graphs of the HSAI.
The HSAI is derived from
the actual number of hospitalized spontaneous abortions, but is expanded
to a common base of 1,000 live births.
This is a reasonable analytical
approach, but it does not accurately convey to the reader the magnitude
of the events actually measured.
The image conveyed
conveyed to
to some
some readers
readers by
by
the Alsea II Report, i.e., that 40 or 50 abortions occurred in the late
spring in the Study area, is misleading.
The mean of the actual number
of hospitalized spontaneous abortions per month are 2.6, 2.4, and 1.5
for the Study, Urban, and Control areas
areas (Appendix
(Appendix 2,
2, Table
Table 33 and
and Figures
Figures
1 to 3).
We have included in Appendix 2 HSAb data compiled by area, zip
code, month, and year (Appendix 2, Tables 4 to 11).
Similarly, the image is conveyed by the Alsea II Report that the
spontaneous abortion rate is much higher in the Study area than in the
Control area.
In fact, the overall ratio of HSAb/live births in the
Study area (188/2,334) is only 22.6% higher than the corresponding ratio
in the Control area (109/1,666), and this is not a large enough
difference at these sample sizes to be statistically significant (based
on analysis of the odds ratio).
the HSAI,
HSAI, month
month by
by
A comparison of the
month, reveals that the Study area had the higher value in 42 months and
the Control area had the higher value in 30 months.
The proportion
(42/72) of months
is not
not
months in
in which
which the
the Study
Study area
area had
had the
the larger
larger }ISAI
HSAI is
(according to the "sign" test) significantly different from 0.5, the
proportion corresponding to the same random variation of HSAI's in the
two areas.
two
The conclusion in the Alsea II report that the HSAI in the Study area is
higher than the Control area is based on an analysis of variance of HSAI
by period, area, and month.
That analysis is invalid, however, due to
the inclusion of "Urban" as one of the area categories.
The Alsea II
Report states that the magnitude of the HSAI values for the Urban area
are not comparable to Study and Control area HSAI's due to the more
frequent handling
handling of
of spontaneous
spontaneous abortions
abortions in
in clinics
clinics in
in the
the Urban
Urban area.
area.
frequent
20
Nevertheless, these values for the Urban area were used in the analysis
of variance, resulting in a highly inflated sum of squares (and
Fvalue) for "areas."
The nimber
number of hospitalized spontaneous abortions were determined from
data collected exclusively from records for inpatients hospitalized
from
from the
the seven
seven hospitals
hospitals within
within the
the three
three areas
areas included
included in
in this
this study.
study.
We do believe the actual numbers determined by EPA in this study are
correct; that is,
is, they
they are
are the
the number
number of
of hospitalized
hospitalized spontaneous
spontaneous
abortions of 20 weeks gestation or less which occurred in the hospitals
included in the study.
However, we believe a number of corrections to
the data need to be made before they can be used as a guide to the true
number of spontaneous abortions occurring in each of the three areas and
Some of these
before
before the
the data
data from
from the
the three
three areas
areas can
can be
be compared.
compared.
corrections must account
account for:
for:
a.
Differences in the age distribution of the populations
b.
Differences in the rates of hospitalization of spontaneous abortion
patients as reflected by physician interviews.
The degree to which health care in the Study area is confounded by
health care provided by physicians from the Urban area.
The effect of failing to make these corrections can easily be
illustrated using the data from the Alsea II Report.
According to that
report, there were 188 hospitalized spontaneous abortions recorded for
patients
patients from
from the
the Study
Study area
area and
and 180
180 in
in the
the Urban
Urban area.
area.
These numbers
reflect (according
Report) aa 70%
70% and
and aa 30%
30%
(according to
to the
the Alsea
Alsea lit
II Report)
hospitalization rate respectively.
Logically, before these numbers can
be compared (or used for computing a hospitalized spontaneous abortion
index) they must be adjusted to a common hospitalization rate.
Failure
to do so results in a substantial underestimate of the number of
abortions in
In the Urban area compared to the Study area.
Using the
2.3)
(70%/30% = 2.3)
uncorrected EPA data, the HSAI should be about 2.3 times (70%130%
21
higher in the Study area than in the Urban area.
If EPA had corrected
the HSAb data for these differences in hospitalization rate, they would
have found the HSAI is higher in the Urban area than in the Study area
area
(Appendix 2, Table
Table 12).
12).
comparable basis.
basis.
Clearly the basic data must be adjusted to a
Failure
Failure to
to do
do so
so means
means the
the HSAb
HSAb data
data represents
represents aa
different percentage of the total number of abortions in one area than
in another.
When the data are corrected to a common hospitalization
rate (100%) and the total number of hospitalized spontaneous abortions
are expressed as a percentage of live births, the values are:
Study area
11.4%
Urban area
14.0%
Control area
9.3%
9.3%
In the United States, the common range of values is 15-25%.
It should be kept in mind that
statistical comparisons of HSAI in
the Study and Control areas is based on the unverifiable and possibly
unjustified assumption that the rates of hospitalization of spontaneous
abortion
abortion patients
patients are
are identical
identical in
in the
the two
two regions.
regions.
The more in error
this assumption is, the more biased the results will be.
Suppose, for
Suppose,
example, that there is actually a 70% hospitalization rate in the Study
area and a 40% hospitalization rate In
in the Control area.
The actual
ratio of HSAb/live births would have been 42.7% higher in the Control
area than the Study area, a statistically significant higher rate (in
terms of the odds ratio).
Comparisons made at a finer level of
aggregation (in time or space) would similarly be affected.
It is
possible that differences In
in hospitalization
hospitalization rates
rates introduce
introduce measurement
measurement
error into the analysis of such a magnitude
magnitude as
as to
to make
make meaningless
meaningless
attempts to compare HSAI in these areas using finelytuned statistical
procedures.
Based on the discussion
discussion above,
above, it
it is
is clear
clear that
that the
the hospitalized
hospitalized
spontaneous abortion indices in the Alsea II Report are in substantial
error and the basic data are not comparable among areas because (I)
22
22
there are differences in the areas and populations studied and (2) data
for hospitalized spontaneous abortions collected on the basis of zip
codes represent different percentages of the total number of abortions
in each area.
We conclude:
The basic data collected in the Alsea II study are not comparable
and therefore are not adequate for determining if differences
exist among the hospitalized spontaneous abortion indices
for the three areas included in this study.
23
SEASONAL CYCLIC PEAKS IN THE HSAI
PART 2.
The Alsea II report concluded there was a significant seasonal cycle in
the HSAI in each area with a period of about four months.
In
particular, they noted an outstanding peak in June in the Study area.
CYCLIC PEAKS
A relatively wide range of variation is common in biological systems and
occurs in the frequency
I.
frequency of
of spontaneous
spontaneous abortions
abortions in
in humans
humans as
as wel
well.
EPA
noted ticyclic
trends" in
in the
the monthly
monthly HSAI
HSAI based on sixyear cumulative
"cyclic trends"
cumulative
data.
We believe these cyclic peaks should be repeated annually if they
are real.
The use of sixyear composite monthly means reduces the
sensitivity of the analysis and there is the possibility that a greater
thanexpected abortion rate for month X in one year will "match" an
unusual spray application in month X in another year.
The HSAb data in the Alsea II Report was presented only as the total
number of abortions over the sixyear period by month.
This summation
prevented readers from evaluating the variation within the data which is
essential for determining whether or not a particular excursion is an
abnormal event or merely a part of the normal variation.
Unless a
particular
particular event
event is
is an
an abnormal
abnormal deviation,
deviation, no
no meaningful
meaningful correlations
correlations
with possible causal agents are possible.
We compiled the HSAb and HSAI data by month by year (Appendix 2,
Table 13 to 15 and Figures 1 to 3).
These data show substantial
variation in the timing of peak HSAb or HSAI among years with regard to
both the existence of peaks and the cyclic nature of their occurrence.
We analyzed the data for cyclic trends by computing autocorrelations of
various lags for the 72 monthly HSAI values from each of the three
areas.
No significant cycling was detected.
Thus, there is
insufficient evidence to warrant the sine wave model used by EPA in the
Alsea II Report.
25
We plotted the monthly HSAI for each of the six
sIx years for each of the
three areas (Appendix 2, Figure 4 to 6).
The
The variation
variation in
in HSAI
HSAI in
in any
any
one month
month over
over the
the six-year
sixyear period
period is
is so
so large
large that a hypothesis
hypothesis of
of
seasonal cyclic peaks is tenuous and of doubtful biological
significance.
To examine whether the frequency of HSAb's was unusually high (or low)
in certain
certain months,
months, we
we conducted
conducted aa chi-square
chisquare goodness of fit
fit test
test of
of
the null hypothesis of a uniform distribution of HSAb's across the 72
months.
Data from the Study
Study and
and Control
Control areas
areas show
show no
no evidence
evidence of
of nonnon
uniformity, i.e., there are no peaks which are unaccounted for by
sampling error from a uniform probability distribution.
The uniform
distribution does not adequately model the data from the Urban area.
EPA reached the same conclusion, but they used only 12 data points
rather than 72.
The results are not
not significantly
significantly altered
altered by
by adjusting
adjusting
the theoretical proportions
proportions (1/72)
(1/72) to
to account
account for
for differential
differential month
month
lengths
lengths or
or differences
differences in
in birth
birth rate
rate between
between months
months within
within areas.
areas.
The expression of the data as HSAI rather than HSAb added to the
impression received by many readers that cyclic peaks existed.
For
For
instance, in the Control area the actual number of hospitalized
spontaneous abortions recorded averaged 1.5 per month and ranged from 0
to 6 in any one month.
Out of the 72 months in the study period, only 2
months had more than four hospitalized spontaneous abortions recorded.
This means that in 70 months, the only numbers recorded were 0,
or 4.
1, 2, 3,
If a I is recorded in March and a 3 is recorded in April, it
appears, graphically, to be a peak, particularly when it is expressed as
HSAI.
In the Control area, I HSAb = an HSAI of about 45.
Thus the
change in HSAb from March to April in this example corresponds to an
increase in HSAI of
of 90,
90, giving
giving the
the distinct
distinct impression
impression of
of aa tpeaklt
"peak"
particularly if I or 2 HSAb's (the most likely values if the mean is
1.5) occur in June.
This concept is illustrated in Appendix 2, Figures
1 to 3.
lto3.
26
THE JUNE PEAK
The "June peak" in the Study area needs special attention for two
reasons: (1) EPA attached special significance to it and the use of
2,4,5T in the Study Area and, more importantly, (2) it illustrates
clearly the likelihood of reaching an erroneous conclusion because of
reliance on highly variable data.
The "June
"June peakt'
peak" in
in the
the study
study area is
an HSAI of 130.4 (based on cumulative data for six years).
This "peak"
represenis
represenls 24 hospitalized spontaneous abortions detected in June in the
Study area in the sixyear study period.
While Lit
it is
variety of
of
is vital
vital to
to test
test data
data for
for significance
significance by a variety
appropriate statistical procedures, it is equally important to examine
the actual or untransformed data.
I.
Examination of this data reveals:
The magnitude of the "June Peak" in the study area represents,
on the average, an increase of 1.4 abortions each June
compared to the mean of 2.6 for all months.
2.
The peak resulted from a substantial increase in abortions
which occurred
occurred in
in only
only one
one year
year -- 1976.
1976.
which
3.
Each of the three areas studied have a peak of HSAB of similar
relative magnitude for at least one month of the sixyear
periods (Table 1).
I).
27
Table
Table 1--Peak
i--Peak monthly
monthly HSAb
HSAb data.-!!
data..!!
Year
Study area
(June)
Control area
(September)
Urban area
(January)
1972
3
11
88
1973
3
6
5
1974
3
2
3
1975
2
2
2
1976
1976
10
0
5
1977
3
1
2
Mean for this month
4.0
4.0
2.0
4.2
Mean for all months
months
2.6
1.5
2.4
Peak as % of mean
for all months
385
385
400
333
!"Underlined value in each column is the largest single HSAb value
for each area.
Averaging the June data in the Alsea II Report gives the impression the
period
increase occurred throughout the study period.
f act that
fact
that it
it occurred
occurred only
only once in June
June 1976.
1976.
It misrepresents the
If we assume that any
month is equally likely to display the maximum HSAI and that the number
of times that the maximum HSAI appears in June follows a binomial
distribution, then the probability of observing a maximum HSAI in at
least one June in six years is about 0.41.
That is, it is not an
unusual occurrence to find a June peak in one of
of the
the six
six years.
years.
The occurrence of the "June peak" in the Study area is critical, to
to two
two
of the three conclusions reached by EPA in the Aisea II Report.
Without
the June 1976 abortion data, the Study area no longer shows three
distinct peaks in the HSAI, thereby making attempts to "align" the data
from
from the
the Study
Study area
area with
with the
the data
data from
from the
the other
other two
two areas futile.
The
The
third EPA conclusion concerning correlation with 2,4,5T use is also
strongly dependent on the June peak.
This conclusion is evaluated in
Part 3, below.
28
28
Despite the weakness of the "cyclic trends," the investigators shifted
the time scale of the HSAI for the various areas to "align" the cycles
seemed to occur when the data are presented as sixyear cumulative
which 8eemed
values.
The purpose of alignment
alignment was
was to
to permit
permit comparison
comparison of
of the
the
magntude
magnitude of
of monthly
monthly HSAI
HSAI between
between areas.
EPA used a "cross correlation" analysis of the differences between the
two
two series
series and
and the
the program
program of
of herbicide
herbicide application
application in
in the
the Study
Study area.
area.
Phase shifting or aligning the two index series before taking
The
The nominal
nominal rationale
rationale is
is clear;
clear; if
if the
the two
two
differences is questionable.
series have different
different underlying
under'ying structures,
structures, with
with an
an additive
additive effect
effect of
of
the "treatment," then a more sensitive analysis of the treatment effect
can be obtained by subtracting the underlying structure from each
series.
But in the presence of a treatment effect, the structure is
"underlying't
modified by that effect, and one cannot easily take out the "underlying"
the
structure (this is analogous to the use of covariance analysis when
when the
"independent" variable is affected by the treatment, a serious violation
of statistical principles).
The simple alternative to the "phase shift" procedure is to assume that
the two series have the same underlying structure, and search for
evidence that the
the differences
differences are
are associated
associated with
with the
the "treatment."
"treatment."
the July difference of 102 HSAI (Appendix 2, Table 12).
Note
This is created
by a very low index in the Urban data, which can hardly be associated
with spray in the Study area.
The Urban area low of November and high
of January, and the Study area lows of January, April, and September and
high of June are of particular interest.
Whatever the value of the
correlation coefficient, one would have difficulty in believing that a
meaningful association exists.
The
The basic
basic flaws
flaws in
in the
the HSAI
HSAI data
data and
and the
the weakness
weakness of
of the
the cyclic
cyclic trends
trends
makes such comparisons not only meaningless but also misleading because
detail may
may
those not able to
to study
study the
the Al
Alsea
sea II
II Report
Report and
and its
its data
data in
in detail
believe the results of such comparisons are sound.
29
We
We conclude:
conclude:
Regularly recurring cyclic peaks in HSAI are not detectable
in data from the areas included in the Alsea II Report.
The
"June peak" of HSAI in the Study area occurred only once
in 6 years and its inclusion in the sixyear average misrepresents
its meaning for purposes of this study.
PART 3.
RELATION BETWEEN HSAI MID 2,4,5T USE IN THE STUDY AREA
The third conclusion in the Alsea II Report is the most important
because it deals directly with the possible relation between the HSAI
and the use of 2,4,5T in the Study area.
EPA concluded there was a
statistically significant correlation between the HSAI and the pounds of
2,4,5T applied per month (after a lag time of 2 or 3 months) when the
sixyear cumulative data were used.
Further, they concluded the results
were "confirmed
tIconfied and
and enhanced"
enhanced" by
by the
the analysis
analysis of the data in two
two three
three
year aggregates.
These conclusions are based on analyses that require two kinds of data,
(a) monthly HSAI and (b) pounds of 2,4,5T used by month in the Study
area, and a temporal relation between spraying and an increase in
abortions.
The bases for the monthly HSAI were examined in both parts
1 and 2 of our critique.
The length of the gestation provides some
insight into the temporal relationship.
LENGTH OF GESTATION
The Alsea II Report concluded there was a 2 to 3 month time lag
following the use of 2,4,5T and the increased frequency of hospitalized
spontaneous abortions in the Study area.
The fetus is most susceptible
to abortifacients during the early stages of gestation.
2,4,5T is not
believed to be so strong an abortifacient as to cause spontaneous
abortions at any time during the gestational period.
If the incidence
of spontaneous abortions increases 2 to 3 months after spraying, there
should be a proportionately greater number of abortions of fetuses of 5
to 13 weeks of age.
This should be reflected
reflected in
in the
the length
length of
of the
the
gestation before the abortion occurs.
9 from the Alsea II Report.
No such peak is evident in Table
The
The gestational
gestational age
age class
class of
of 55 to
to 13
13 weeks,
weeks,
Is slightly smaller proportionally in the Study area as compared to the
is
Urban
Urban or
or Control
Control areas.
areas.
These data do not support the third conclusion
of the Alsea II report.
31
2,4,5T SPRAY DATA
In the Alsea I Study, EPA collected 2,4,5T spray data for a 400 square
mile area (called the Alsea Basin) around the residences of the women
involved in that study.
No additional data
data on
on spray
spray use
use was
was collected
collected
in the Alsea II Study.
EPA apparently assumed that the spray data used
in the Alsea I study is representative of the 2,4,5T use in the much
larger Alsea II Study area.
We compiled and plotted (to the nearest section) data from both public
and private forest land management groups on 2,4,5T use for the entire
1600 square mile Study area.
Data were collected from USDA Forest
Service, USD1 Bureau of Land Management, Oregon State Department of
Forestry, Starker Forests, Willamette Industries, Georgia Pacific,
Publishers Paper, Boise Cascade, and Champion International (Appendix 3,
Table I,
1, and Figures 1 to 6).
For purposes of this critique, we have
combined use data for silvex and 2,4,5T together and Labelled
labelled it
2 ,,4 4,
2
, 5T.
5T.
The data used by EPA does not compare well with the data we collected
(Table 2).
We divided the annual use data into two periods, spring
(before June 30), and summer (after July 1) to reflect the two major
periods of use and because the "June peak" in the study area would
reflect spring, but not summer, spraying.
This
This table
table shows
shows the
the following
following important
important facts:
facts:
1.
EPA substantially underestimated the use of 2,4,5T in the
Study area and failed to detect the increasing proportion of
spraying done after July 1 between 1972 and 1976.
Clearly the
statistics for the "Alsea Basin" developed by EPA in the Al sea
I study are not a good indicator of 2,4,5T use in the Alsea
II Study area.
32
2,4,5T use
use for
for the 400square mile
Table 2--Comparison of statistics on 2,4,5T
the entire
entire1600
1600 square
square mile
mile "Study
"Study Area."
Area."
"Alsea
ttAlseaBasin't
Basin" as used by EPA and for the
2.4.5T used in
2,4,5T
Year
Season
(pounds)
(pounds)
1972
1973
1974
1975
1976
1977
Alsea Basin-'
Basin'
Area!
Study Area1"1
(pounds)
% of use in
Study area)
spring
11,151
11,151
406
3.6
5 umme r
summer
2,758
2,758
363
13.2
spring
20,580
20,580
444
2.2
s umme r
summer
3,429
3,429
50
1.6
spring
7,970
7,970
207
2.6
5 umme r
summer
2,201
2,201
240
10.9
spring
12,305
12,305
760
6.2
summe r
summer
5,380
5,380
211
3.9
spring
18,731
18,731
4,131
22.1
summe r
summer
9,333
9,333
0
spring
14,519
14,519
3,104
0
summer
summe
r
1"2,4,5T
'2,4,5T (and silvex) use data we compiled for the entire study area.
12,4,5T use data as compiled by EPA and reported in Alsea II Report.
33
-21.4
--
2.
The proportion of the total 2,4,5T use In the Study area
which EPA detected based on use in the Alsea Basin changed
markedly
markedly over time.
The effect Is pronounced in
In the two
threeyear aggregates (1972-1974, 1975-1977) EPA used in their
analysis.
In the first threeyear period, 2,4,5T use in the
Alsea Basin was 2.7%
2.77 of the use In
in the Study area, but in the
second threeyear period, use In
in the Alsea Basin was 17.5%
l7.57 of
the use in the Study area, more than a sixfold increase.
Increase.
EPA reported there was a marked increase In
in spring spraying in the
second of the threeyear periods (according to EPA, 1,057 lbs in
1972-1974 versus 7,995 lbs in 1975-1977, a 7.6fold
7.&fold increase).
reality, there was little change.
In
The actual pattern of use was 39,621
lbs in 1972-1974 compared to 45,555 lbs In
in 1975-1977 (a 1.15fold
increase).
The increase In
in 2,4,5T use in the second threeyear period
reported by EPA is obviously the result of a larger fraction of the
total 2,4,5T use occurring in the Alsea Basin portion of the Study area
(EPA used only the Alsea Basin as the data source for both the Alsea I
and II studies).
studie8).
34
SPRAY DATA
THE HSAI
HSAI VERSUS
VERSUS 2,4,5T
2,4,5T SPRAY
DATA
THE
EPA's comparison of patterns of use relative to the "June peak" of
abortions for these 2 threeyear aggregates is faulty for two reasons
which, because of the errors they involve, reinforce each other.
reasons are:
The
The
(1) the June peak of HSAI occurred only because of the
1976 data, therefore, it is obvious that the second of the 2 threeyear
thethe
first, first,
(1975-1977) will
will have
have aa much
much higher
higher June
June HSAI
HSAI than
than
aggregates (1975-1977)
the EPA
EPA data on 2,4,5T use is six times closer to being
and (2) the
level
complete for-the second aggregate; therefore, it appears that the level
of 2,4,5T use increased substantially in the second threeyear
aggregate when, in fact, it did not.
2,4,5T was 1973, not 1976.
The year of highest spring use of
Conclusions
Conclusions which
which use
use comparisons
comparisons based
based on
on
the spray data collected by EPA are in error.
The EPA investigators concluded that there was a significant association
between the pounds
pounds of
of 2,4,5T
2,4,5T applied
applied arid
and the
the HSAI
HSA1 22 to
to 33 months
months later
later
in
in the study area.
The fundamental pieces of evidence EPA used to reach
herbicide
this conclusion are: (1) that the maximum application of the herbicide
summing pounds used in April
was in the month of April (determined by summing
(2) the
the maximum
maximum HSAI
over the 6 years covered by the study), and (2)
appeared roughly 2 months later in June (determined by summing
hospitalized spontaneous abortions and live births over the 6 years to
for June, 1972-1977).
HSAI for
1972-1977).
calculate a single HSAI
Their conclusions are weakened when the data are analyzed in less
aggregated form.
In Table 22 of the Alsea II Report, where the HSAI is
based on two threeyear periods (rather than a single sixyear period),
only one of ten Spearrnan
correlations of
of HSAI
HSAI with
with spray
spray amount
amount achieve
achieve
Spearman correlations
significance at the 0.05 level.
Even if all actual correlations were
zero, it would not
not be
be unusual
unusual for
for one
one of
of aa sample
sample of
of ten
ten correlations to
achieve significance at that level.
Whatever associations were observed between 2,4,5T use and HSAI are of
dubious meaning due
due to
to the
the level
level of
of aggregation
aggregation of
of the
the data
data over
over time
time
and space;
for sixyear
six-year totals
totals of
of HSAb's
HSAb's (or
space; i.e.,
i.e., computing
computing1-ISAI
HSAI for
(or at
at
best two three-year
threeyear totals)
totals) and
and over
over aa large
large geographic study
study region
region in
in
which application
application of
of the
the spray
spray was
was highly
highly non-uniform.
nonuniform.
The dangers of
attributing this
this type
type of
of macro-unit
macrounit association
association (so-called
(socalled '1ecological
attributing
'1ecological
correlations") to individuals have received much attention in the
statistical literature.
The Alsea
Alsea II
II Report
Report reveals
reveals the
the effect
effect of
of using
using three-year
threeyear rather
rather than
than
sixyear aggregated
six-year
aggregated data.
data.
To illustrate this point further and to
emphasize the effect of the June 1976 observation in the Study area, we
disaggregated the data to the monthly level, yielding 72 observations of
HSAI.
Due to problems previously discussed, we did not compare HSAI
among areas but only considered the Study area in investigating the
effect
use on
on HSAI.
HSAI.
effect of
of 2,4,5-T
2,4,5T use
Despite other problems with the basic
data collected by EPA, we assume here for purposes of illustration that
the HSAI data are adequate for statistical analysis.
With this assumption,
we examined the HSAI data for an association with the actual pounds of
2,4,5T used
2,4,5-T
used in
in the
the Study
Study area.
area.
In Appendix 3, Table 2, we show monthly HSAI and actual pounds of
2,4,5T used
2,4,5-.T
usedininthe
theStudy
Studyarea
areaonona acumulative
cumulativebasis
basis covering
covering 1.5,
1.5, 2.5,
2.5,
and 3.5 months prior to the monthly HSAI's.
The cumulative use values
are intended to account for time lags between herbicide use and a
possible spontaneous abortion response as well as accumulated exposure.
For example,
example, aa 2.5-month
2.5month accumulation
accumulation of
of 2,4,5-T
2,4,5T use
use corresponding
corresponding te
to
the HSAI for June of 1972 represents the total pounds of herbicide used
in April, May, and half of that used in June of 1972.
The combined use
information for
information
for the
the months
months March-April
MarchApril and
and May-June
MayJune was
was apportioned
apportioned on a
monthly basis in a manner compatible with the monthly use distribution
given in Table 4 and Figure 8 of the Alsea II Report.
Specifically, for
the March-April
MarchApril combination,
combination, 30%
30% was
was attributed
attributed to March and
and 70%
70% to
to
April; for
for the
the May-June
MayJune combination,
combination, 75%
75% was
was attributed to May
May and
and 25%
25%
to June.
36
We plotted monthly HSAI values and the 1.5, 2.5, or 3.5 month
cumulative use data to determine if there was a relationship between use
of 2,4,5T and HSAI (Appendix 3, Figures 7 to 9).
There is no
relationship between HSAI and pounds of 2,4,5T used except as
influenced by the HSAI of June 1976.
That point on each plot is
distinctively apart from the remaining points.
Formal linear regression
and correlation analysis were conducted to investigate the degree and
statistical significance of the relationship between HSAI and pounds of
2,4,5T use.
In order to assess the influence of the June 1976
observation, these analyses were conducted both including and omitting
that observation.
The resulting Pearson correlations are given in Table
3, for the three time lags.
When the June observation is omitted, the
Pearson correlation values are small in magnitude and statistically
nonsignificant.
Table 3Correlation between HSAI and 2,4,5T use for three time lags,
including
including and
and omitting
omitting June
June 1976
1976 observation.
observation.
Cumulative period of
Including June 1976
Omitting June 1976
2,4,5T use before
abortions
-----Pearson
-----Pearson correlation
correlation ------------------------1.5 months
0.0120
2.5 months
02047
0.2047
3.5 months
0.2707*
-0.0014
0. 1349
0.1349
*P < 0.05
(Particularly when one realizes that the squares of these correlations
represent the proportion of the variance in HSAI that is "explained" by
2,4,5T use).
When the June 1976 observation is included, the
correlations all increase in magnitude and the 3.5 month time lag shows
significance at the 0.05 level.
The June 1976 observation also has a
large effect on the least squares lines.
The regression lines for the
three time lags that are obtained both including and excluding the June
1976 observation are plotted on Figures 7 to 9 (Appendix 3) and the
regression equations are in Table 3 (Appendix 3).
For the 3.5 month
time lag, the slope of the line based on all 72 points is 2.4 times
larger in magnitude than the slope of the line when the June 1976 point
is excluded.
We believe this analysis shows that the sixyear cumulative data fail to
meet
meet the
the criteria
criteria of
of annual
annual recurrence.
recurrence.
In fact, the June 1976 HSAI
dominates the data (Appendix 3, Figure 10).
38
POTENTIAL FOR HUMAN EXPOSURE
Why was there such an increase in HSAI in June 1976?
The answer is not
known because there are many factors which could cause such an increase
to be recorded.
For purposes of this critique, however, it is most
important to examine the spray data
data to
to determine
determine if
if it
it varies
varies in
in some
some
way that might account for the increase in HSAI in June 1976.
The EPA spray use data suggests 1976 was the heaviest period of 2,4,5T
use in 1972-1977.
Our data also shows 1976 was the highest year in
total, but it is the spring spray period that is of predominant
importance
importance for
for HSAI
HSAI values
values for
for early
early summer
summer months.
months.
Our data shows 1973
as the peak year for
for spring
spring spraying
spraying (20,292
(20,292 Ibs)
Ibs) followed
followed by
by 1976
1976
(18,731 ibs) and 1977 (14,519 ibs).
Ibs).
both 1973 and 1977.
The peak HSAI occurs before May in
On this basis, it appears the timing of peak
monthly HSAI values are not particularly related to either timing or
amount of spraying.
The area where the patient lived (based on zip code) is important in
determining
determining the
the likelihood
likelihood that
that exposure
exposure to
to spray
spray material
material would
would occur.
occur.
We tallied the number of hospitalized spontaneous abortions by month,
year, and zip code in the Study area (Appendix 2, tables 4 to 9). In
June 1976, 10 spontaneous abortions were recorded; 8 were in zip cocLe
areas for the 4 urban areas adjacent to the ocean (Florence, Waidport,
Waldport,
Newport, and Lincoln City).
areas.
The other two were inland urban or rural
The geographic distribution of hospitalized spontaneous
abortions in
abortions
in the
the Study
Study area
area in
in June
June for
for 1972-1977
1972L977 are in Table
Table 4.
4.
39
Table 4--Qeographic distribution of HSAb in Study area for June,
1972-1977.
Year
Number of
of hospitalized
hosita1ized spontaneous
spontaneous abortions
abortions for June
Four urban coastal areas
All other parts of Study area
TQtal
1972
1
2
3
1973
1
2
3
1974
2
1
33
1975
2
0
2
1976
8
2
10
1977
2
1
3
16
8
24
TOTAL
The number of hospitalized spontaneous abortions are relatively constant
in the inland urban and rural areas of the Study area.
they are also quite constant in the coastal uthan areas.
Except for 1976,
The reason for
the umusual1y
uusua11y large
large rmrnber
number of
of HSAb's
HSAb's in
in the
the coastal
coastal urban
uran areas
areas in
in June
June
1976 is not known, but the likelihood of 2,4,5T involvement seems
remote.
The number of spontaneous abortions, which occurred in June
1976 in each of these four cities, is not larger than those occurring at
other times, but the occurrence of high values in three cities in the
same month is unique.
unique.
A plot of the 2,4,5T use by site within each of the zip code "zones" in
the Study area revealed several associations concerning proximity of
2,4,5T use and population centers (Appendix 3, Figures 1 to 6).
EPA
attempted to show proximity and, therefore, probable exposure (and
possible cause) by simply presenting the fact that 2,4,5T was used and
spontaneous abortions occurred in an area approximately 60 miles long
and
and 30 miles wide.
Exposure potential would be shown more clearly by
identifying the residence and activities of each person suffering an
RSAb in relation to the most proximate sites of 2,4,5T use.
not
not possible
possible in
in this
this study.
study.
40
This is
We took the next best method, which is to associate HSAb's and sites of
2,4,5T use by zip code (Appendix 3, Table 4).
There are 5 zip code
areas in which no 2,4,5T was used and 67 HSAb's or 36% of the total
occurred.
Five zip code areas included 81% of the 2,4,5T use sites and
51 (27%)
(277) of the HSAb's.
One
One of
of these
these five
five zip
zip code
code areas,
areas, 97439
97439
(Florence), accounts for 33 of the 51 HSAb's in that set.
Since there
were no 2,4,5T spray sites within 2 miles of Florence and only 2 sites
within 4 miles, one can observe that the remaining 4 "high use" zip code
areas account for 70% of all the 2,4,5T spray sites in the Study area
and only 9.67
9.6% of the
the HSAb's
HSAb's (Table
(Table 5).
5).
Table 5--Number of sites treated with 2,4,5T and number HSAb for the
six years, a comparison of zip codes with the fewest and the
most sites treated.
Zip code
Sites treated
H SAb
Fewest sites treated
97391
0
97388
0
97341
0
97369
0
97365
Total
40
0
2.
0
Most sites treated
97390
97390
134
97343
97343
86
97324
224
97394
121
97439
Total
33
653
If the HSAb's in the four urban coastal areas (Lincoln City, Newport,
Waldport, and Florence) are distributed proportionally between the urban
41
and rural components of those populations, then 76 HSAb's involved urban
residents of those cities.
There were no sites of 2,4,5T use within 2
miles of any of those cities.
About 56%
567 of the total HSAb's detected in
the study area were in the four urban coastal areas.
Only l.57
1.5% of the
2,4,5T use sites were within 3 miles of these urban areas.
This method
of viewing probable exposure is not as precise as we would like, but it
is substantially more precise than the method used by EPA in the Alsea
II study.
Based on this discussion and analysis it is clear to us that EPA's third
conclusion is wrong.
There is no substantive difference in the pattern
of 2,4,5T use in the spring between the 1972-1974 and the 1975-1977
periods; thus, conclusions that an increase In
in HSAI reflects or is
correlated with increased use of 2,4,5T is in error.
Furthermore, we
find there is no June peak of HSAI in the Study area except in 1976.
The increase in June 1976 occurred exclusively in the four coastal urban
communities where exposure to 2,4,5T spray material is least likely to
occur.
We conclude:
There
There is
is no
no demonstrable
demonstrable relation
relation between
between the
the patterns
patterns of
of
2,4,5T use and HSAI in the Study area.
42
CONCLUS IONS
The conclusions we reached as a result of this critique are geared to
the three conclusions EPA reached in the Alsea II Report.
EPA Conclusion I - "The 1972-1977 abortion rate index for the Study Area
is significantly higher than those for either the Control or the Urban
Area."
We found:
a.
There are differences in topography, climate, and demography among
the three areas which make comparisons among these areas tenuous.
b.
There are substantive differences in medical practice among
these areas and EPA failed to account for the high percent of the
medical care for residents of the Study area which is delivered in
the Urban area.
Consequently, the data are incomplete and the
actual percentages of spontaneous abortion
abortion patients
patients who
who are
are
hospitalized for the three areas are incorrect in the Alsea II
Report.
The hospitalization
hospitalization rates
rates given
given in
in the
the Alsea
Alsea II
II Report
Report are
are
sufficiently different among areas to completely offset the unadjusted
difference in the HSAI between the Study and Urban area reported by
EPA.
EPA's finding of a significant difference in HSAI between the
Study and the Control
Control areas
areas is
is invalid.
invalid.
We conclude:
The EPA HSAI values are not reliable because of incomplete
data collection and failure to account for patterns of and
differences in medical practice among areas.
Conclusions
arising from comparisons of data among the three areas are
error.
likely to be in error.
43
EPA Conclusion II - "There is a statistically significant seasonal cycle
in the abortion index in each of the areas with a period of about 4
months.
In particular, there is an outstanding peak in June in the
Study area.'t
Study
area."
We found:
a.
There is substantial variation in the magnitude of the HSAI for any
one month (all Januarys, all Februarys, etc.) among the 6 years in
the study.
In the Study area the peak monthly HSAI for the year
occurred in 5 different months for the 6 years of the study.
June
had the peak HSAI only in 1976.
b.
What appears to be a peak HSAI in June in the Study Area is, in
fact,
fact, the
the consequence
consequence of
of aa single
single large
large excursion
excursion from
from the
the norm
norm
which occurred only in 1976.
If the June 1976 data point is
recognized for what it is, the basis for alignment of the data from
the Study area with the data from the other two areas disappears.
Therefore, the EPA conclusion that there is a seasonal cycle of
HSAI with a period of four months in the Study area is faulty,
because it rests solely on the June 1976 data point.
We conclude:
The seasonal cyclic peaks seen by EPA in the sixyear cumulative
data are.
are consistent
consistent with
with aa model
model of
of random
random variation.
The
data are highly variable from area to area and from year to
year.
The "June peak" in the Study area occurred only in
one year of
of the
the sixyear
sixyear study
study and
and should
should not
not be
be presented
pesented
as a repetitive event.
EPA Conclusion III - "There is a statistically significant
crosscorrelation between the Study area spontaneous abortion index and
the spray patterns in terms of pounds applied by months in the Alsea
Basin, 1972-1977, after a lag time of 2 or 3 months.
The results based
based
on the sixyear aggregate of abortion and spray data are confirmed and
enhanced by the analysis of the two threeyear aggregates."
44
We found:
a.
The spray data EPA collected in the 400squaremile Alsea
Aisea Basin
gave a seriously misleading conception of the spray data for the
According to the EPA data 9,052
1600squaremile Study area.
pounds of 2,4,5T were used in March, April, and May, but according
to the records of all the major forest land owners in the Study
area 85,176 lbs were used.
b.
More seriously, the spray data EPA collected represents only 2.7%
of the actual use for the 1972-1974 aggregate, but 17.5% for the
1975-1977
1975-1977 aggregate.
EPA's incomplete spray data should not have
been compared between time periods.
The alleged increased use of
2,4,5T during the 1975-1977 seasons was actually due to more
complete collection of spray data rather than increased use.
Complete data show that there was little difference in the amount
of 2,4,5T sprayed in the spring in the two threeyear aggregates
(39,621 pounds in 1972-1974 versus 45,555 pounds in 1975-1977).
d.
There is no statistically significant cross correlation between the
Study area HSAI and our more complete data on 2,4,5T use excepting
for the apparent increase in June HSAI.
In the second threeyear
aggregate of data, this was wholly due to a single high HSAI
value which occurred in 1976.
All other June HSAI values
appear usual, despite the fact 1973 was the year of peak use
of 2,4,5T during the spring.
Deletion of the single
single June
June
1976 HSAI value removed the significant correlation between
the amounts of 2,4,5T used and the magnitude of the monthly
HSAI which was reported by EPA.
The increase in HSAI in June 1976 occurred only in four coastal
urban community zip code areas where exposure to spray materials is
least likely to occur.
45
We conclude:
There is no significant correlation between the pattern of 2,4,5T
use
use and
and the
the HSAI
HSAI in
in the
the Study
Study area.
area.
EPA's conclusion is faulty
because (1) their data on 2,4,5T spray use is seriously
incomplete and in substantial error, and (2) the "June peak"
is based on an event which occurred in only I of the 6 years.
The three conclusions of the Alsea II Report are expressed in
statistical terms by EPA.
of the data.
This implies
Implies a careful and unbiased analysis
There are other, and
and perhaps
perhaps more
more appropriate
appropriate methods
methods of
of
statistical analysis than the ones used by EPA; however, we believe the
most serious flaws in the study are in the incomplete and inaccurate
data which were used in the data analysis.
The conclusions of any study
can be no better than the quality of the basic data, regardless of the
sophistication of the data analysis.
We believe EPA investigators erred by failing to analyze, with
sufficient care and logic, the characteristics of the three areas, the
comparability of the various data bases for abortion statistics, and the
completeness of the spray data before it was subjected to statistical
analysis.
EPA erred seriously in each of the three conclusions in the
Alsea II Report.
If there is a relationship between herbicide use and
miscarriages in the "Alsea Basin" and its surrounding area, it is not
apparent and cannot be tested using the data from the Alsea II study.
ri
APPENDIX
APPENDIX 11
POPULATION STATISTICS
from census
different from
Since census data are not available for units different
tracts for
for areas
areas outlined
outlined by
by zip
zip codes
codes (which defined the boundaries of
tracts
estimation
the
the Study
Study area)
area) or
or for
for unincorporated
unincorporated villages,
villages, aa method of estimation
employed by county planning agencies was used.
The number of post
delivery routes,
routes, and the
office
office boxes
boxes in
in city
city delivery
delivery routes,
routes, rural
rural delivery
by aa factor (in this case the
post office itself can be multiplied by
factor used was 2.3) to estimate population.
Such
Such estimates
estimates are
are not
not
precise because some rural routes start from the center of a small town,
some P.O. boxes are used by rural dwellers, and some nonresidences
(i.e., business offices) cannot be subtracted from other deliveries.
However, the estimates so derived are sufficiently accurate to
characterize a region.
Our figures are based on the most recent Post
Office data or 1970 census figures.
The population levels undoubtedly
changed during the 1972-1977 study period but precise data are not
available.
13 towns and
Table 4, shows the
the comparative
comparative population
population figures
figures for
for 13
The
villages in the 3 studied areas from 3 different sources.
differences for Ontario are probably typical.
The figure of 8200
8200 is
is an
an
older census figure, 8900 is a more recent census figure, and both of
the urban area; 11,474
these figures are bounded by the city limits, not the
incorporates the area known locally as "greater metropolitan Ontario."
2, and
and 33 in
in text
text and
and Figures
Figures
The zip
zip code
code boundaries
boundaries on
on maps
maps (Figures
(Figures 1,
1, 2,
The
1 to 6 in Appendix 3) are arbitrary to the extent that the boundaries
roads serviced by post
approximate crest
crest lines
lines halfway
halfway between
between the
the roads
office rural deliveries.
The Post Office definition
definition of
of zip
zip codes
codes is
is by
by
roads, not by areas fitted together like the pieces of a puzzle.
in "zip code maps" prepared by
means there are some discrepancies in
various
various groups
groups studying
studying this
this problem.
problem.
47
This
This
Table 1--Population distribution based on estimates from Post Office
Statistics
Population
Location
Study area
and Rural)
Rural)
Coastal (Urban and
35,327
35,327
Inland (Urban and Rural)
18,136
TOTAL
53,463
Urban (Coast & Inland)
34,212
Rural (Coast & Inland)
19,251
TOTAL
TOTAL
53,463
Urban area
Corval lis
us
Corval
Urban
46,310
Rural
5,229
TOTAL
TOTAL
51,539
Control area
Urban
16,559
Rural
6,143
TOTAL
48
22,702
Table 2--Population distributions among urban and rural components
I'
the Study
Study area.2-'
area.
in the
Zip code
Urban centers (Population <2000)
Components
Rural.
Urban
Total
Total
COASTAL ZONE
COASTAL
ZONE
97367
Lincoln City
8,758
474
9,232
97365
Newport
6,725
1,625
8,350
97394
Waldport
2,696
1,085
3,781
97439
Florence
3,542
5,040
8,582
21,721
8,224
29,945
3,21 I
24,932
2,161
L0,385
5,372
35,317
Subtotal
Villages (Population <2000)
97341,
97341, 97366 97369
97388 and 97487
Subtotal
TOTAL
INLAND
INLAND ZONE
ZONE
Urban centers
97370
Philomath
1,943
3,758
5,701
97391
Toledo
4,545
1,468
1,468
6,013
Subtotal
6,488
5,226
11,714
Subtotal
TOTAL
2,828
9,316
3,594
3,594
8,820
6,422
18,136
34,248
19,205
53,453
Villages
Villages
97324, 97326, 97343
97357, 97380, 97390
97453 & 97480
GRAND TOTAL
GRAND
TOTAL FOR
FOR STUDY
STUDY AREA
AREA
.!iEstimates
-'Estimates from Post Office statistics
Table 3--Population distribution among urban and rural components in the
Urban and Control areas'
Zip code
Community
Components
Components
Rural
Urban
97330
Corvallis
42,550
97332
0.S.U. Dorms
97321
Albany
5,229
47,779
3,760
3,760
TOTAL FOR
URBAN AREA
Total
34,001
4,837
38,838
80,311
10,066
90,377
11,474
2,500
13,974
CONTROL AREA
97914
Ontario
97913
Nyssa
2,941
1,718
4,659
97918
Vale
2,075
2,075
1,764
3,839
97906
Harper
69
161
230
16,559
6,143
22,702
TOTAL FOR CONTROL AREA
Estimates from
from Post Office statistics
- Estimates
50
Table 4Comparison of urban population estimates from various sources.
Location
Portland State University
Population Research Center
Post Office statistics
Alsea II
Report
Study area
Lincoln City
8,758
4,890
4,200
Newport
6,725
7,150
5,200
aldport
2,696
1,250
No listing
1istin
Florence
3,542
3,900
2,250
2,250
Depoe Bay
1,033
730
No listing
Yachats
955
525
No listing
Siletz
844
900
No
No listing
listing
Corvallis
42,550
40,500
37,000
Albany
34,001
34,001
26,150
21,000
11,474
8,950
8,200
Nyssa
2,941
3,000
2,900
Vale
2,075
1,900
1,850
1,850
Urban area
Control area
Ontario
Harper
No listing
69
51
250
APPENDIX 2
HOSPITALIZED
HOSPITALIZED SPONTANEOUS
SPONTANEOUS ABORTION
ABORTION STATISTICS
STATISTICS
The hospitalized spontaneous
spontaneous abortion
abortion data
data was
was taken
taken from
from the
the individual
individual
Alsea II
II
anonymous case records
records compiled
compiled by
by the
the EPA
EPA as
as part
part of
of the
the Alsea
study.
The totals obtained by us differ from the EPA totals as follows:
Study area, 188 vs 188; Urban area, 174 vs 180; and Control area, 107 vs
109.
The source of these differences could not be determined since the
EPA did not publish their detailed compilations, i.e., by month, by year
in the Alsea II Report.
We do not believe these differences are
purposes of
of this
this critique.
critique.
important for purposes
53
Table lATotal number of births by months for the Study, Urban, and
1972_1977..!."
Control areas, 1972_1977..1"
Urban area
Study area
Control area
January
194
338
124
February
188
188
353
124
124
March
202
344
126
126
April
189
335
131
131
May
201
201
357
155
June
228
378
378
145
July
203
315
315
156
August
212
351
351
131
September
204
342
154
October
October
170
343
136
November
172
337
155
December
Deceniber
181
327
129
2,344
4,120
1,666
Sixyear Total
!"From Table 10 of EPA Alsea
Alsea II
II Report.
Report.
Table lBExample set of corrected sixyear total number of births compiled
by EPA (May, 1979) subsequent to the Alsea II study.
Sixyear Total
Difference
Difference
Study area
Urban area
Control area
2,902
3,803
2,044
+558
317
+378
54
2-Number of
Table 2--Number
of births
births corresponding
corresponding to
to the
the month
month of
of spontaneous
spontaneous abortions
abortions
l9721977))'
in the Study, Urban, and Control areas (Oregon l972_l977).2J'
Urban area
area
Urban
Study area
Control area
January
208.8
208.8
338.3
338.3
146.3
146.3
February
206.8
345.0
142.6
142.6
March
191.8
341.5
145.6
April
177.8
340.4
143.6
May
177.9
334.8
142.3
June
184.0
334.3
130.5
July
189.7
342.0
126.5
August
193.0
345.7
125.4
September
195.6
342.5
129.0
129.0
October
196.7
196.7
346.9
346.9
138.7
November
208.7
358.1
147.3
December
213.4
350.7
350.7
148.1
148.1
2,344.0
4,120.0
1,666.0
Total
Total
!"From
'From Table 11 of EPA Alsea II Report.
55
Table 3--Hospitalized Spontaneous Abortions (HSAb) (raw data).
Year
JAN
FEB
MAR
2
2
1
1
5
2
2
JUNE
Month
JUL
APR
MAY
AUG
SEPT
3
3
3
3
4
0
4
3
5
4
33
2
1
1.
2
1
1.
3
3
1
1.
2
3
2
2
2
6
OCT
NOV
DEC
00
2
5
5
3
4
2
3
1
3
11
4
1
33
00
5
1
1.
3
TOTAL
Study area
1972
1973
1974
1975
1976
1.977
1977
TOTAL
Average
1
4
4
1
1
10
10
22
22
2
1
1.
3
2
4
3
3
3
33
4
1
2
22
1
2
2
37
34
23
31
32
31
]0
10
17
1.7
18
11
16
24
20
17
1.7
9
15
16
15
188
1.7
2.8
3.0
3
1.8
2.7
4.0
3.3
2.8
1.5
2.5
2.7
2.5
2.5
31.3/year
2.6/month
Urban area
1972
8
4
44
22
0
4
5
2
33
43
5
0
47
3
1973
1.973
2
3
2
4
33
3
1
1.
4
38
1974
1.974
3
5
3
1
4
55
5
6
3
1
2
L975
1976
I977
2
4
3
1
1.
L
1
1
0
22
2
2
38
18
5
2
]
1
0
0
1
1
0
3
20
1
1
4
Z
2
00
2
0
3
0
0
0
2
0
0
2
5
1
11
17
25
16
15
L6
16
1.5
15
4
10
16
19
7
15
15
174
TOTAL
Average
4.2
2.7
2.7
5
2.5
2.7
2.7
2.5
0
0
3
1
2.7
3.2
1.2
2.5
29.0/year
2
.4/month
2.4/month
2
1
0
2
2
1
6
1
2
2
3
2
1
1
33
1
2
2
2
4
2
0
0
0
0.7
1.7
1.7
00
1
1
0
Control area
1972
1973
1.974
974
1.975
1975
1976
1.977
1977
TOTAL
Average
0
1.
1
2
0
0
0
3
0
1
3
5
2
3
1
3
2
1
2
0
1.1
4
0
1
1
22
0
0
1
9
19
26
25
8
2
22
2
4
0
0
3
1
11
2
1
2
20
12
4
5
6
12
12
1.2
6
S
14
1.4
107
0.8
1.0
1.0
1.0
1.3
2.0
0.7
14
1.2
2.3
2.3
1.5
2.0
2.0
56
2.0
2.3
2.3
17.8/year
I .5/month
1.5/month
ii:
Cl)
:i:
u'
C
0
8
0
mean
necn HSAb
6
2.6
U,
0
C
0
4C
0
rAl
0.
C,,
-o
.!::
2
0
40.
U,
0
n
0
0
0
20
30
40
60
50
70
Months Since January I, 1972
I
2
-,
2
1972
I
2
1973
1974
-)
-)
1975
1976
1977
Figure 1--Monthly Hospitalized Spontaneous Abortions (HSAb) in Study
area, 1972-1977.
57
URBAN AREA
largest
Jorgest single value
2
mean
HSAb=2.5
2.5
mean HSAb
U)
0
a,
I
I
20
tO
40
30
60
50
50
70
Months Since January 1, 1972
z
Iii
z
W
z
w
z
z
Iii
-,
1972
1973
1974
-)
1975
976
1977
Figure 2--Monthly
2--Monthly Hospitalized
Hospitalized Spontaneous
Spontaneous Abortions
Abortions(IISAb)
(USAb) In
in Urban
Urban
area, 1972-1977.
58
CONTROL
CONTROL AREA
largest single
largest
single value
volue
mean HSAb
0
20
10
40
30
60
Months Since January
70
1972
wz
-)
1972
972
_D
1973
973
-)
-D
1974
_)
-)
-)
1975
_)
-)
_D
1976
-)
1977
Figure 3--Monthly Hospitalized Spontaneous Abortions (HSAb) in Control
area, 1972-1977.
59
Table 4-1972 Hospitalization Spontaneous Abortions (HSAb) in the Study area
area by
by nionth
month
and zip code of patient.
Location &
zip code
JAN
FEE
MAR
APR
MAY
Month
JUNE JUL
AUG
SEP
OCT
NOV
DEC
TOTAL
1
2
1
7
1.
3
URBAN
Coast
97367
(Lincoln City)
97365
(Newport)
97394
(Waldport)
97439
(Florence)
1
1
1
1
1
1
1
1
3
I
I
22
9
Subtotal
21
Inland
97391
(Toledo)
97370
(Philomath>
(Philomath)
1
1
2
1
1
3
1
1
1
Subtotal
Urban Subtotal
6
9
30
RURAL
Coast
97341
97366
97369
97376
97388
97498
Subtotal
Inland
97324
97326
97343
97357
97380
97390
97453
97480
GRAND TOTALS
2
2
3
3
3
3
5
4
0
2
Subtotal
5
Rural Subtotal
37
55
5
37
Table 5-1973 Hospitalized Spontaneous Abortions (HSAb) in the Study area by month
and zip code of patient.
Location &
zip code
JAN
FEB
MAR
MAY
Month
JUNE
NOV
JULY
DEC
TOTAL
URBAN
Coast
97367
97365
97394
97439
5
3
1
1
1
2
Subtotal
5
14
I
Inland
97391
97370
1
1
66
3
1
Subtotal
9
Urban Subtotal
23
RURAL
Coast
97341
97366
97369
97376
97388
97498
0
0
0
0
Subtotal
Subtotal
Inland
Inland
97324
97326
97343
97357
97380
97390
97453
97480
3
2
0
0
0
2
1
1.
GRAND TOTAL
Subtotal
9
Rural Subtotal
11
4
61
2
33
34
Table
Table 6-1974
6-1974 Hospitalized
Hospitalized Spontaneous
Spontaneous Abortions
Abortions (HSAb)
(HSAb) in
in the
the Study
Study area
area by
by month
month
and zip code of patient
Month
JAN
FEB
MAR APR
JULY
JULY
AUG
SEPT
SEPT
OCT
NOV
DEC
1
TOTAL
2
1
2
6
0
I
1
LL
Subtotal
8
T16
1
44
1
Subtotal
5
Urban Subtotal
21
21
0
1
00
00
0
0
Subtotal
TT
0
0
0
0
1
0
0
0
Subtotal
T
Rural Subtotal
Subtotal
Rural
2
1
62
62
4
1
23
23
Table 7-1975 Hospitalized Spontaneous Abortions (HSAb) in the Study area by month and
zip code of patient.
JAN
FEB
FEB
MAR
APR
MAY
Month
JULY
JUNE
JIJNE
AUG
SEP
OCT
NOV
1
1
1
I
DEC
I1
4
2
11.
Sub total
Subtotal
1
Subtotal
Urban Subtotal
1
Subtotal
Sub total
1
Subtotal.
Subtotal
Rural Subtotal
0
63
5
13
TOTAL
Table 8-1976 Hospitalized Spontaneous Abortions (HSAb) in the Study area by month
and zip code of patient.
Month
JAN
FEB
MAR
APR
MAY
JUN JULY
2
1
2
AUG
SEP
1
11
OCT
NOV
1
TOTAL
7
1
6
2
Subtotal
18
18
1
1
DEC
1
33
3
5
1
I
Subtotal
6
Urban Subtotal
24
24
2
0
00
0
0
22
1
Subtotal
0
0
00
00
22
22
00
0
Subtotal
Rural Subtotal
1
64
2
2
1
8
32
32
Table 9-1977 Hospitalized Spontaneous Abortions (HSAb) in the Study area by month and
zip code of patient.
Location &
zip code
JAN
FEB
MAR
APR
MAY
Month
JuN JUL
JUN
AUG
SEP
SE
OCT
NOV
DEC
TOTAL
1
7
Coast
97367
97365
97394
97439
1
I.
1
5
1
2
1
4
I
1
Subtotal
18
Inland
1
97391
97370
1
1
1
1
4
1
I
Subtotal
Urban Subtotal
Subtotal
RURAL
23
Coast
00
97341
97366
97369
97376
97388
97498
0
0
0
1
Subtotal
2
Inland
0
97324
97326
97343
97357
97380
97390
97453
97480
0
0
0
2
0
2
2
Subtotal
Rural Subtotal
2
GRAID TOTAL
GRAND
65
1
2
2
8
31
Table 10Hospitalized
lORospitalized Spontaneous !bortions
Pbortions (HSAb) in the Urban area by month,
year, and zip
zip code
code of
of patient
patient
Location &
zip code
JAN
FEB
1
0
MAR
APR
MAY
JUN
Month
JUL
AUG
SEP
OCT
NOV
DEC
TOTAL
1972
97330
9730
35
(G&ya11js)
(Gr,allis)
9321
9Th21
,1
1.
845342O45
(Alhany)
(Aihany)
TOTALS
,03
1
1.
0
1
0
2
0
1
8
L
1.
2343
19fl
L93
97330
97321
TOTALS
5
0
33
7
2
33
2
33
0
3
3
0
11
33
1
0
0
0
0
1
0
0
0
4
Y7
0
5
1
3
2
3
2
4
3
3
1
4
38
97330
97321
TOTALS
2
2
3
11
2
44
11
1
0
00
2
1
0
0
11
s
5
I
1
3
T
33
2
3
3
0
0
5
1
3
27
11
TT
1
0
0
0
00
00
2
11
1
11
11
1
1
0
1
0
T
T
0
1
1
7
0
0
1
00
0
3
15
15
0
0
00
0
1
0
0
1
1
1.
0
33
5
20
0
0
0
5
0
1
5
1
11
0
1
00
0
0
0
2
3
5
1i
1
4
10
10
16
16
19
35
1974
733O
1
3
97-321
97-21
1
1
33
0
TOTALS
2
4
T
3
2
1
2
3
2
0
0
1
1
5
2
1
3
4
0
00
00
00
0
2
11
00
1
00
T
T
1976
97330
97321
TOTALS
0
1977
1.977
97330
97321
TOTALS
GRAND TOTAL
2
1
1
00
0
0
22
11
1
25
16
15
!
i
16
16
15
15
66
7
15
iS
1-5
15
2
17
174
174
Table llHosptalized
llHosptalized Spontaneous
Spontaneous Abortions
Abortions (}1SAb)
(HSAb) in
in the
the Control
Control area by month,
year, and zip code of patient
Year,
location &
zip code
JAN
FEB
MAR
APR
MAY
Month
JUN JUL
AUG
SEP
OCT
NOV
DEC
TOTAL
TOTAL
2
5
1972
97914
(Ontario)
97913
(Nyssa)
97918
(Vale)
97906
97906
(Harper)
TOTALS
1
33
1
1
0
0
1
0
0
0
0
0
1
1
1
11
2
1
0
2
2
9
4
1
1
1
1
10
1
11
66
11
22
2
1.9
1
1
2
1973
1973
97914
97913
97918
97906
TOTALS
1
1
11
1
2
0
0
3
1
1
11
11
1
0
1
6
2
2
1
l
3
2
3
0
19
1974
97914
97913
97918
97906
1
3
1
5
4
3
26
3
1
20
1
3
00
1
1
3
5
97914
97913
97918
97906
2
1
2
4
22
TOTALS
33
TOTALS
TOTALS
16
2
22
1
3
2
2
1
11
1975
1
1
1
2
3
0
1
33
4
2
11
1
1
0
1
2
2
2
2
4
25
1976
97914
97913
97918
97906
11
TOTALS
2
0
1
1
0
97914
97914
97913
97918
97906
22
22
2
33
TOTALS
22
22
22
4
0
0
0
3
3
11
1
1
2
11
2
2
20
12
4
7
14
9
5
6
10
12
6
8
14
107
4
1
1
1
2
1
1
2
0
11
1
1.
0
2
0
3
11
1
0
0
0
11
8
11
2
17
17
1977
1977
GRAND TOTALS
1
1
1
2
1
0
67
Table 12--Monthly HSAI adjusted to 100% hospitalization rate.1'
Study area
Urban area
Difference
JAN
68.7
246.3
178
FEB
117.4
164.3
MAR
134.0
146.3
146.3
APR
88.4
156.7
MAY
NAY
128.4
169.3
47
12
68
41
JUN
186.3
149.7
149.7
37
37
JUL
150.6
48.7
102
AUG
125.9
106.0
20
SE?
SE?
65.7
165.3
165.3
100
OCT
108.9
182.7
74
NOV
109.6
65.3
44
DEC
100.4
152.0
Average
115.4
146.0
52
31
1"Monthly HSAI x 0.1 = Hospitalized spontaneous
spontaneous abortion
abortion as
as aa
percentage of live births.
Table 13--Hospitalized
Table
13--Hospitalized Spontaneous
SpontaneousAbortion
AbortionIndex''
Index''by
bymonth
monthand
andyear
yearfor
forthe
the Study
Studyarea.
area.
27.9
27.9
49.7
49.7
34.9
34.9
58.8
58.8
36.3
36.3
42.3
42.3
93.8
93.8
62.0
62.0
90.1
90.1
130.3
130.3
106.3
106.3
88.0
88.0
46.0
46.0
76.2
76.2
76.6
76.6
70.3
70.3
80.8
80.8
62.5
62.5
135.1*
135.1*
101.4
101.4
97.7
97.7
94.9
94.9
126.2
126.2
61.4
61.4
30.5
30.5
57.5
57.5
56.2
56.2
80.5
80.5
325.0
125.0
33.8
33.8
33.8
33.8
325.7*
325.7*
63.3
63.3
93.2
93.2
30.7
30.7
61.0
61.0
57.5
57.5
28.1
28.1
93.8
93.8
67.6
67.6
67.6
67.6
65.2
65.2
189.9*
189.9*
93.2
93.2
0
0
152.4
152.4
28.7
28.7
84.3
84.3
79 88
79
62.5
62.5
33.8
33.8
101.4
101.4
97.7
97.7
31.7
31.7
31.1
31.1
92.0
92.0
30.5
30.5
114.9*
114.9*
28.1
28.1
59.2
59.2
0
135.1
135.1
97.7
97.7
100.0
100.0
62.1
62.1
92.0
92.0
122.0
122.0
57.5
57.5
84.3
84.3
93.8
93.8
101.4
101.4
101.4
101.4
97.7
97.7
158.2*
158.2*
124.2
124.2
0
61.0
61.0
143.7
143.7
140.5
140.5
94.8
94.8
31.0
31.0
29.6
29.6
29.6
29.6
30.7
30.7
31.6
31.6
12.2
12.2
32.6
32.6
32.8
32.8
34.8
34.8
35.6
35.6
March
April
April
May
June
June
July
July
August
August
September
September
October
October
November
Ijeceinber
December
ratio of the
*Indic5 tea
*Indic5
ten
births for
index for
for aa given
spontaneous abortion
abortion index
given year.
year.
the largest
the
largest hospitalized
hospitalized spontaneous
amongthe
the 66 years.
been divided
divided equally
equally among
interval have
have been
yeirs.
births for the
the 6-year
6-year interval
as abortions/bOO
abortions/bOO births.
births.
births based
based on
on a
a 5-month
5-month moviug
moving average,
average, and
and is
is expressed
expressed as
numberofoflive
live births
to the
to
the corresponding
corresponding number
study, the iosptalized
The monthly
The
numberofof hospitalized
hospitalized spontaneous
spontaneous abortions
abortions
index is
is the
the ratio of the number
abortion Index
defined by
defined
by the
theEPA
EPA study, the iosptaIized spontaneous
spontaneous abortion
Average
Average
42.6
42.6
43.3
43.3
50.1
50.1
96.6
96.6
42.7
42.7
82.1
82.1
87.0
87.0
115.9
115.9
51.9
51.9
29.0
29.0
144.9*
144.9*
57.9
57.9
34.7
34.7
February
February
125.0
125.0
44.8
44.8
47.8
47.8
57.4
57.4
28.7
28.7
57.4
57.4
57.4
57.4
28.7
28.7
57.4
57.4
34.8
34.8
January
January
Standard
Standard
Deviation
Deviation
Mean number
Mean
number of
of
births
births
Average
Average
1972-1977
IL8
Month
I 8
1U?A
Z161
cii
L61
9161
L61
1161
39.1
39.1
28.9
28.9
0
0
0
0
17.4
17.4
86.8
86.8
69.4
69.4
00
57.6
57.6
August
August
42.7
42.7
42.3
42.3
17.1
17.1
24.8
24.8
51.2
51.2
29.3
29.3
34.2
34.2
34.2
34.2
55.6
55.6
68.3
68.3
55.5
55.5
51.2
51.2
62.8
62.8
58.5
58.5
December
December
for aa given
index for
*Indicate
spontaneous abortion
abortion index
hospitalized spontaneous
*Indicates the
given year.
year.
the largest
largest hospitalized
the 6
6 years.
years.
have been
been divided
divided equally
equally among
among the
interval have
for the
for
the 6-year
6-year interval
as abortions/
1000births.
births.
abortions/l000
expressed as
and is
births based
is exprqssed
based on
on aa 5-month
5-month moving
average, and
to the
of live
live births
to
the corresponding
corresponding number
number of
moving average,
births
The
The monthly
monthly births
spontaneous abortions
abortions
tndexisis the
the ratio of the qumber
abortion index
qumberofof hospitalized
hospitalized spontaneous
the hospitalized
hospitalizedspontaneous
spontaneous abortion
theEPA
EPA study,
defined
defined by
by the
study, the
ratio of the
17.9
17.9
19.5
19.5
16.7
16.7
0
0
33.5
33.5
16.7
16.7
16.7
16.7
33.5
33.5
59.7
59.7
November
November
Average
Average
12.6
12.6
54.8
54.8
86.5*
86.5*
17.3
17.3
34.6
34.6
51.9
51.9
51.9
51.9
86.5
86.5
7.8
57.8
October
October
27.7
27.7
46.7
46.7
35.0
35.0
17.5
17.5
0
0
105.1*
105.1*
52.5
52.5
70.1
70.1
57.1
57.1
September
September
37.8
37.8
18.1
18.1
11.7
11.7
0
0
0
0
0
0
0
0
35.1
35.1
35.1
35.1
57.0
57.0
July
July
V9Z
0
0
33.6
33.6
44.8
44.8
35.9
35.9
0
0
17.6
17.6
89.8
89.8
53.8
53.8
71.8
71.8
55.7
55.7
June
June
21.7
21.7
47.8
47.8
35.8
35.8
71.7
71.7
17.9
17.9
71.7
71.7
35.8
35.8
53.8
53.8
55.8
55.8
May
May
50.7
50.7
47.0
47.0
0
0
52.9
52.9
0
0
17.6
17.6
123.5*
123.5*
88.1
88.1
56.7
56.7
April
April
21.5
21.5
43.9
43.9
17.5
17.5
17.5
17.5
52.7
52.7
52.7
52.7
70.2
70.2
52.7
52.7
56.9
56.9
March
March
34.2
34.2
46.4
46.4
17.4
17.4
34.8
34.8
69.6*
69.6*
86.9
86.9
0
0
69.5
69.5
5.5
57.5
February
February
41.7
41.7
73.8
73.8
35.4
35.4
88.6*
88.6*
88.6
88.6
141.8*
141.8*
35.4
35.4
Standard
Standard
Deviation
Deviation
53.2
53.2
Average
Average
1972-1977
1972-1977
56.4
56.4
births,
biizths,
ntunber of
of
Mean ntunbr
January
January
Month
Index1' by
by month
andyear
yearfor
forth.e
tke Urban
Urban area.
area.
month and
Table
Spoütaneoua Abortion
Abortion Index1"
Table 14--Hospitatzed.
14--Hospitaied. Spoütaneous
L6T
A
£L6
I
'.'L61
9L61
cLbT
1L61
I-.
78.9
34.5
60.0
63.3
38.2
47.4
0
0
142.2
42.2
45.9
0
0
84.4
45.9
0
93.0
86.6
211.0*
91.7
94.8
143.5
93.0
43.2
40.7
42.2
45.9
0
47.8
279.1*
43.2
81.3
81.0
67.3
00
0
47.4
957*
46.5
0
81.3
81.3
81.0
32.8
23.7
21.8
21.1
20.9
21.5
23.1
24.6
24.7
May
June
July
August
September
October
November
December
39.1
39.1
97.6
38.7
33.2
41.8
79.7
93.0
43.3
54.2
94.5
64.1
47.8
46.5
86.6
40.7
81.0
71.7
0
0
40.5
29.0
81.3
161.9
88.1
121.5
94.1
*Indicates the largest hospitalized spontaneous abortion index for a given year.
for the 6-year interval have been divided equally among the 6 years.
to the corresponding number of live births based on a 5-month moving average, and is expressed as abortions/1000 births.
The monthly births
defined by the EPA study, the hospitalized spontaneous abortion index is the ratio of the number of hospitalized spontaneous abortions
Average
77.9
97.6
167.4*
0
167.4*
167.4'
125.5
125.5
0
23.9
April
957*
48.3
48.2
82.6
41.3
124.0
41.3
0
0
24.2
March
47.8
34.3
28.0
84.0
0
42.0
0
0
42.0
23.8
February
44.9
82.0
82.0
82.0
82.0
0
123.0
Standard
Deviation
123.0
Average
1972-1977
1911
1916
1975
Year
1974
24.4
24.4
Mean number of
births
January
January
Month
year for
for the
the Control
Control area.
area.
Index.0 by month and year
Table 15--Hospitalized Spontaneous Abortion Index21
0
0
MONTHS
LEGEND
deviation
standard
One
-6
-5
Cr)
'
Mean for /972-1977
MonThly
HSA//
Monthly HSA
/972 - /977
/972-1977
Figure 4--Monthly Hospitalized Spontaneous Index (HSAI) and Hospitalized Spontaneous Abortions
(HSAb) in the Study area, 1972-1977. The HSAb is approximate because of monthly shifts in
the live birth rate used to calculate HSAI.
:i:
U)
4
200
300
MONTHLY HSA / IN STUDY A REA
J
F
M
A
M
J
MONTHS
J
A
S
0
N
One
J
standard
deviation
Mean for /972 -/977
X
® Monthly HSA/
0
(I)
C')
[IJ
21
3
4
t
7
8
Figure 5--Monthly Hospitalized Spontaneous Abortion Index (HSAI) and Hospitalized Spontaneous Abortions
HSAb is
is approximate
approximate because
because of
of monthly
monthly shifts in
(HSAb) in the Urban
Urban area,
area, 1972-1977.
1972-1977. The ilSAb
the
the live
live birth
birth rate
rate used
used to
to calculate
calculate HSAI.
HSAI.
I
Cl)
'I
/972-1977
LEGEND
L. E6'ENO
MONTHLY HSA
HS4 I
/ IN URSA
URSA NN AA REA
REA
J
F
M
standard
deviation
fOne
A
X Mean for /972-/977
® Mofh/y H$A /
LEGEND
M
j
MONTHS
J
A
S
0
N
D
4
I
I
(t)
Figure 6--Monthly Hospitalized Spontaneous Abortion Index (HSAI) and Hospitalized Spontaneous Abortions
(HSAb) in the Control area, 1972-1977. The HSAb is approximate because of monthly shifts
in the live birth rate used to calculate HSAI.
I
U,
300-
MONTHLY HSA I IN CON TROL AREA, /972-1977
APPENDIX 3
2,4,5T USE STATISTICS
The 2,4,5T use statistics were supplied by the major forest land
owners in the Study area.
Data were supplied by USDA Forest Service,
USD1 Bureau of Land Management, Oregon State Department of Forestry,
Starker Forest, Georgia
lamette Industries,
Industries, Publishers
Publishers
Georgia Pacific,
Pacific, Wil
Willamette
Paper, Boise Cascade, and Champion International.
Spray sites were
plotted to the nearest section in most cases.
Figures 1 to 6 show the 2,4,5T use sites and the zip code boundaries.
In most instances, sites were plotted in the center of the section, thus
the sites are accurate to within one mile.
drawn with arbitrary guidelines.
The zip code boundaries were
Contrary to the implication
implication of
of the
the
maps, zip codes cover delivery routes or roads and not necessarily contiguous
areas.
They are transformed into "areas" which appear to be contiguous
by constructing arbitrary boundaries between delivery routes, usually
along ridge lines.
The choice of where to draw the boundary line can,
therefore, include or exclude a considerable amount of area, some which
may have been sprayed with 2,4,5T.
75
Table 1Table
1- 2,4,5-T
2,4,5-Tuse
useinin Study
Studyarea.!!
areaY
Suer
Spring
Year
MAR
APR
(dormant)
(4ormant)
MAY & JUN
AUG
JUL
TOTAL
SEP
(foliar)
(foliar)
2,4,5-T
Use in
in Acres
Acres
2,4,:5-T Use
1972
1972
1973
1973
1974
1975
1976
1977
TOTALS
4,198
4,198
4,085
4,085
1,782
1,782
3,486
3,486
7,242
7,242
6,479
6,479
6,671
6,671
3,838
3,838
3,896
3,896
2,643
2,643
1,298
1,298
27,272
27,272
18,773
18,773
421
87
128
606
5,652
5,652
11,919
11,919
6,487
6,487
9,198
9,198
13,099
13,099
7,777
7,777
1,858
1,858
1,644
1,644
1,356
1,356
00
0
0
0
50
0
0
60
0
0
0
2,606
2,606
5,371
5,371
ilO
110
477
1,112
1,112
261
384
384
284
5,304
5,304
1,646
1,646
3,118
3,118
1,817
1,817
4,916
4,916
4,029
4,029
13,379
13,379
6,502
6,502
4,273
4,273
3,600
3,600
3,255
3,255
1,140
1,140
0
0
0
65,721
65,721
19,247
19,247
7,345
7,345
15,526
15,526
230
427
112
1,026
1,026
739
54,132
54,132
acres
acres
2,4,5-T Use
2,4,5-T
Use in
in Pounds
Pounds
j972
j972
1973
1974
1975
1976
1977
TOTALS
10,674
L0,674
13,790
13,790
3,697
3,697
8,705
8,705
L5,476
0
50
0
180
0
13,909
13,909
23,721
23,721
10,171
10,171
17,685
17,685
28,064
28,064
14,519
14,519
108,069
108,069
pounds
pounds
!'USDI bureau
11USDI
8ureauofofLand
LandManagement
Management
forsilvex
silvex-- silvex
silvex and
datadata
is is
for
and 2,4,5-T
2,4,5-Tare
arecxnbined
cxnbined
in
in this
this critique.
critique.
76
II STUDY IAREA
LSA/-\
'A LS/-\
LINCOLN
CITY
ZIP CODE BOUNDARIES
SPRING /972
SUMMER /972
/
A
A A - SILETZ
9734I;
97367
A/-A
AA
/
I
r
,'
97380
3a
97365
(
(
Aa
('-'-.
1/
NEWPORT
£
t
.J97391
AQLIINA
RIVER
97326
H
L
N
/
a
A
L
/
,'ILOMATN
Lu
a
97394
a
1/
/
I
I
:,
-'
I.-'
'1
AL.SEA
liI
I
ALSE
L
7
RIVER
A£
4J324
4J
324
--,
£
A
£
A
A
LI-
LA
97439
)
1
S
/
,,1'
)
A
974. ./'
974O
-
S
/
,'.
S
S
.7
)
S
i;;::c.
1SIUSLAW
1S/USLAW
)
-N-
çRIVER
SCALE IN MILES
-
)
Figure l--2,4,5-T
Figure
l--2,4,5-T use
use plotted
plotted by
by section
section and
and season
season in
in Study
Study area,
area, 1972.
1972.
77
LS/-\ II STUDY AREA
£Aa/I
A
a
SPRING /973
SPRING
/973£
J SUMMER
I
a
/973'
RIVER
A
a
A
L
a.
97326
A
a
97343
A
a
----..
A\
*1 '-
S
.
afl
97370
*l
Lu
A394
a394
a
aa
LA
AA
aa
A
a
A
a
LA ""
aa
9739tA AJJ,
:
Li
'i-
c)
-'
1_.gL
1_á\
//
AAA 4
AAAA
4.
AAAA
aaaa
-,
Pa
974
:974
AAK a
aaf
A
-N-
A
a
0246
SCALE IN MILES
Figure 2--2,4,5-T
2--2,4,5T use
use plotted
plotted by
by section
section and
and season
season in
in Study
Study area,
area, 1973.
1973.
78
ii STUDY AREA
LINCOLN
CITY
ZIP CODE BOUNDARIES
SPRING
SPR'ING /974
1974
tA/I SUMMER
SUMMEfi /974
1974
ge0
S/LETZ
RIVER
NEN&
A
.A A
N SSAL A
97376 i
IiJ
A
£
.4*L
4a* LA LA
I
t
I
c)
.-_J La
£
/
394 I a
:
/a
A
A
WALOPORT
,/ 97370
A
7
£
/
I
£
£
£ A £
£ I
I
--
_J
A
£ £
197394
.1
At*
?
(1
1
c)
£
LA
/.cFA
RIVER
A
/
\
9739
I
97324
:1
4
'.-
S
k.--&--.
I
0246
SCALE IN MILES
Figure 3--2,4,5T use plotted by section and season in Study area, 1974.
79
Figure 4--2,4,5-T use plotted by section and season in Study area, 1975.
LSA II STUDY IAREIA
LINCOLN
£
CITY
/
AZIP
&Z7PCODE
CODEBOUNDARIES
BOUNDARIES
,
SPRING /976
SPRING
/976A
a
)
J
SUMMER /976
1976
:S/LETZ
(R/VER
97341'
97367
aL:a
97369
-
V..-a
365
NEWPORT
:'
.1CV/N
a'
'.--..__
R''CR
97326
a
97366,.
\
97376
Lu
(U
I
a-..S
W394
Aa
La
/ I
---.-..
LA
La
A
A
/PHILOMATH
L
/
A
a
/
/
WALDPORT
a
973w
1
"4
.
A
/
a A
a
7
/
/
/
_I
a
--
A
97394
,
a
5ç..jJ'4A
-,4LSEA £
..
af
RIVER
97324
-:
'4-
a
A
r ....
4aaa
£
c)
a
/
--.La
A
:>-
97439
97480
A
La
a
a
7'
".
) .0
'I
t
..e. .:,
97453
'\
-..
.'
a
'\
SIUSLAW
(R/VER
A
PLDREN
..... .
.-
,_..'
-
o
6
SCALE IN MILES
/
Figure 5--2,4,5T use plotted by section and season in Study area, 1976.
81
II STUDY AE
L,NCOLN!LSE
CITY/I
/
ZIP CODE BOUNDARIES
fj
SPRING /977 A
) SUMMER /977
j
,JSILETZ
)
734Ij4
L-%A\
ft
I
97380L1
I
/
'-S.
97343
NEWPORt\
LJ
97343
SAS
/£
LJ
£1
9T394;11
c)
A
/
A
A
A
AAA
/
/
£
A'
WALOPORT
/
/
,.
_/
97394
*6
97390
A
6A
9P32
A
A
LL
9M39
97480
97453
O 24 6
SCALE IN MILES
Figure 6--2,4,5-T use plotted by section and season in Study area, 1977.
82
Table
Table 2-IiSAI
2-IiSAIand
and2,4,5-T
2,4,5-Tuse
useinin the
the Study
Study area.
area.
Cumulative 2,4,5'-T
Cumulative
2,4,5-.T use
use for
for
selected time
selected
time periods
periods prior
prior
1'
Year
Year
Month
HSAI
2,4,5-T1'
2,4,5-T-'
used
to
to
1.5
1.5
L973
1973
January
January
February
March
April
April
May
May
June
June
July
July
August
August
September
Septnber
October
October
November
December
57.4
57.4
57.9
57.9
93.8
93.8
101.4
101.4
101.4
101.4
97.7
97.7
158.2
158.2
124.2
124.2
January
January
February
Aprili
April1
May
June
June
July
July
August
August
September
September
October
October
November
December
28.7
28.7
144.9
144.9
125.0
125.0
0
135.1
135.1
97.7
97.7
100.0
100.0
62.1
62.1
92.0
92.0
122.0
122.0
57.5
57.5
84.3
84.3
January
January
February
February
March
April
April
May
June
June
July
July
August
August
September
September
October
October
November
December
57.4
57.4
29.0
29.0
62.5
62.5
33.8
33.8
101.4
101.4
97.7
97.7
31.7
31.7
31.1
31.1
92.0
92.0
30.5
30.5
114.9
114.9
28.1
28.1
MII%
1974
0
61.0
61.0
143.7
143.7
140.5
140.5
0
00
10,67
10,674
2.5
2.5
3.5
3.5
months
months
months
poundspounds-
pounds
pounds
1972
1972
abortion'
abortion1
0
0
1,601
1,601
0
0
00
0
1,601
1,601
6,938
6,938
10,853
10,853
7,889
7,889
1,033
1,033
2,054
2,054
2,758
2,758
1,646
1,646
0
0
1,601
1,601
6,938
10,853
10,853
11,091
11,091
8,505
8,505
2,412
2,412
2,877
2,877
2,758
2,758
1,646
1,646
0
0
1,112
1,112
1,646
0
0
0
0
6,938
6,938
7,651
7,651
417
675
1,935
1,935
1,646
1,646
0
0
0
0
0
0
0
0
0
0
2,068
2,068
8,964
8,964
12,091
5,689
5,689
1.756
1.756
1,820
1,820
3,143
3,143
2,068
2,068
13,790
13,790
0
8,964
8964
16,228
16228
15,342
L5,342
6,632
6,632
3,446
3,446
3,404
3,404
3,168
3,168
50
0
0
0
0
0
0
00
6
502
6 502
'
261
3,118
3,118
50
0
0
0
3,697
3,697
4 273
4
273
'
384
1,817
1,817
0
0
0
0
50
00
405
405
1,753
1,753
3,490
3,490
3,739
3,739
1,452
1,452
1,293
1,293
1,817
1,817
1,753
1,753
4,299
4,299
5,627
5,627
4,465
4,465
2,361
2,201
2,201
1,817
1,817
0
0
0
0
0
0
2,068
2,068
8,964
8,964
16,228.
16,228.
19,479
19,479
16,285
16,285
8,322
8,322
5,030
5,030
3,429
3,429
3,168
3,168
50
0
0
405
405
1,753
1,753
4,299
4299
6,436
6,436
6,353
6,353
5,566
5,566
3,269
3,269
2,201
2,201
1,817
1,817
0
Table
2-(Continued)
Table 2-(Continued)
Cumulative 2,4,5-T
Cumulative
2,4,5-T use
use for
for
selected time
selected
time periods
periods prior
prior
abortion-'
to abort.Lon'
to
3.5
2.5
1.5
months
Year
pounds
pounds
pounds
pounds
1975
L975
L976
1976
January
January
February
March
April
April
May
June
June
July
July
August
August
September
September
October
October
November
December
57.4
57.4
57.9
57.9
93.8
93.8
67.6
67.6
67.6
67.6
65.2
65.2
l89.2
l89.2
93.2
93.2
0
152.4
152.4
28.7
28.7
84.3
84.3
January
February
March
April
April
May
June
June
July
July
August
August
September
October
October
November
December
28.7
28.7
115.9
L15.9
125.0
125.0
33.8
33.8
33.8
325.7
325.7
63.3
63.3
93.2
93.2
30.7
30.7
61.0
61.0
57.5
57.5
28.L
28.1
January
January
February
February
March
Iarch
April
April
May
June
June
July
July
August
August
September
September
October
October
November
November
December
57.4
57.4
87.0
87.0
62.5
62.5
135.1
135.L
101.4
101.4
97.7
97.7
94.9
94.9
124.2
124.2
6L.4
61.4
30.5
30.5
57.5
57.5
56.2
56.2
Septber
L977
1977
ounds
7i'ounds
0
0
0
0
0
0
0
0
1,306
5,658
7,444
7,444
3,150
3,L50
L,042
1,042
2,742
2,742
5,006
5,006
180
L80
0
0
1,306
5,658
10,055
L0,055
9,244
9,244
3,742
3,742
3,642
3,642
5,290
5,290
5,096
5,096
180
L80
0
0
1,306
5,658
10,055
L0,055
Ll,855
11,855
9,835
9,835
6,342
6,342
6,190
6,190
5,380
5,380
5,096
5,096
180
L80
0
0
0
0
0
0
0
0
0
0
2,321
2,32L
10,059
L0,059
12,053
12,053
2,848
2,848
3,466
3,466
7,319
7,319
4,029
4,029
0
0
0
2,321
2,321
10,059
L0,059
16,697
L6,697
13,681
13,681
5,907
5,907
8,132
8,132
9,333
9,333
4,029
4,029
0
0
0
2,321
10,059
10,059
16,697
16,697
18,324
18,324
16,740
16,740
L0,574
10,574
10,147
10,147
9,333
9,333
4,029
4,029
0
0
0
0
0
0
0
2,007
2,007
8,696
9,793
9,793
998
285
0
0
00
0
0
2,007
2,007
8,696
13,807
13,807
10,363
L0,363
L,140
1,140
285
0
0
0
0
8 700
8'
3 600
3
600
'
284
4,916
180
L80
0
0
L5 476
1
'
'
3 255
3
255
'
5,304
5,304
4,029
0
3
379
11
months
months
'
1 140
L40
'
0
0
0
0
0
0
and May-June
March-April and
of
2,4,5-T are
are combined
combined for
for March-April
May-June
of 2,4,5-T
as
apportioned 30/70
30/70 for
for March-April
March-April and
and 75/25
75/25 for
forMay-June
May-June as
are apportioned
1Pounds are
in Alsea
in
Alsea II
II Report.
Report.
0
0
0
2,007
2,007
8,696
L3,807
13,807
14,377
14,377
10,505
10,505
L,140
1,140
285
0
0
0
®
®
a ®
2,4,5-T USED (lbs.)
.i.I.
16,000
Without June /976
With June /976
20,000
in the
of 2,4,5-T
2,4,5-T sprayed
sprayed in
Figure 7--Monthly Hospitalized Spontaneous Abortion Index (HSAI) and pounds of
previous 1.5 months in the Study area, 1972-1977. Multiple points indicated by( ).
000t7
00
I.
0008
(9,
(/)
(ci)
°®
300
000'
00O'
k®®
(t
(F
00
()
()cXD® ®
2)
®
®®
®
® ®®
-
12,000
12,000
2,4,5-1
2,4,5-1 USED
USED (lbs.)
(lbs.)
8000
Without June /976
W/tb June /976
Figure 8--Monthly
8--Monthly Hospitalized
Hospitalized Spontaneous
Spontaneous Abortion
Abortion Index
Index (HSAI)
(HSAI) and
and pounds
pounds of
of 2,4,5-T
2,4,5-T sprayed
sprayed In
inthe
the
previous 2.5 months in the Study area, 1972-1977. Multiple points indicated by( ).
I
U)
I.
I.
-.'
Dl:,
2,4,5-1 USED (lbs.)
[o
Without June /976
Figure 9--Monthly Hospitalized Spontaneous Abortion Index (HSAI) and pounds of 2,4,5-T sprayed in the
previous 3.5 months in the Study area, 1972-1977. Multiple points indicated byS( ).
I
U)
20C
30C
Table 3Regression equation (least squares) of cumulative 2,4,5T use and
HSAI.
Including June
Including
June 1976
1976
Omitting June 1976
-
1.5 month
nonth
H
80.110
0.0003017T
80.110 +
+ 0.0003Ql7T
H
-
77.886 - 0.0000188T
77.886
2.5 month
H
71.900 +
71.900
+ 0.0023896T
H =
75.523 I- 0.0006487T
75.523
O.0006487T
3.5 month
H -
67.354 + 0.O0Z580lT
O.0025801T
a
R -
72.447 + 0.00l0751T
72.447
B
T
-
HSAI
-
pounds of 2,4,5T used in the indicated period of time prior to occurrence
of HSAb.
90
1972
973
974
I.1CAI ,,,S
4
_ r ii
1,,
975
A,
976
977
Figure
Figure 10--Monthly
10--Monthly Hospitalized
Hospitalized Spontaneous
Spontaneous Abortion
Abortion Index
Index (HSAI) and
and 2,4,5-T
2,4,5-T use
use in
in Study
Study area,
area, 1972-1977
1972-1977
100
100
150
150
200
200
250
250
300
300
0
5
I
0
I
I
0
0
0
0
0
00
0
0
0
0
17
Il
0
0
0
0
0
0
0
97341
97343
97357
97365
97366
97366
97367
97369
97370
97376
97380
0
0
3
0
0
0
0
0
0
0
0
00
0
0
t
0
3
I
0
0
18
0
0
0
0
0
1
0
0
66
0
2
0
9
0
24
0
17
0
0
0
8
0
5
6
2
0
0
13
0
0
0
0
3
97388
97390
97391
97394
97439
97453
97480
97480
97498
TOTALS
I
0
0
5
00
I
9
Il
I
6
0O
35
0
45
141
3
107
1
33
2
13
6
15
4
0
I
IS
107
2
0
27
22
II
I
10
15
26
2
13
26
16
0
0
0
0
106
3
0
51
0
0
0
II
Il
21
4
17
0
0
0
86
0
67
0
0
0
6
0
0
0
0
19
00
0
0
8
0
0
0
0
0
0
0
0
0
77
0
0
12
0
8
0
0
6
0
1
0
I
0
2
0
0
0
00
0
2
0
0
0
0
0
0
2
0
0
0
0
0
0
0
2
0
0
0
0
0
Snnmer
1
19/7
19
0
5
0
0
61
Spring
2
Summe
3
1976
0
5
0
0
1
0
0
4
46
Spring
0
0
0
0
0
0
5
II
Il
6
0
0
0
0
0
4
0
12
28
4
Summer
1$
19/5
Spring
Summer
Spring
1974
code.
0
I
S'immer
2!tp
3
913
by sengon
season and
3
97326
5
9
97324
2,4,5To
SprLng
0
Summer
3
1972
35
Spring
8
Zip code
Table 4Number of aites treated with