"It is not my contention that chemicals never be used. I do contend that
we have put poisonous and biologically potent chemicals in the hands of
persons largely or wholly ignorant of their potential harm"
(Rachel Carson, Silent Spring, 1964)
Pesticide Poisonings:
Perspective is Reality
Cecil Tharp
MSU Pesticide Education Specialist
Pesticide Poisoning is common in
Montana.

31% of private applicators surveyed have been at least mildly
poisoned by exposure to pesticides. Always minimize bad habits
while wearing recommended PPE to minimize exposure.
Are Montana applicators protecting
themselves from Pesticides?
Do you wear PPE that is required on the product label while applying
pesticides?
Wear required
PPE while
applying
pesticides
11%
42%
Do not wear
required PPE
while applying
pesticides
47%
While applying
pesticides, did
not know what
was on the
product label
Why are they not protecting themselves?
‘practical reasons’
Applicators Focus on Acute Toxicity
 Toxicity
which occurs within seconds,
minutes or hours.
 Applicators focus on acute toxicity
and corresponding signal words..
Signal Words / LD50
Table 2. Signal words found on pesticide labels.

Caution (Category IV)  You can drink the
stuff
Does ‘Caution’ indicate PPE is not
needed?
 Often
disregarding PPE statements
on pesticides which show low acute
toxicity
Signal
Word
PPE
Bad Habits also lead to Pesticide
Poisoning
1/5 applicators surveyed smoked or chewed during
application of pesticides in Montana. Chewing and smoking
while applying pesticides increases exposure to pesticides
and may result in pesticide poisoning.

Have you smoked or taken a
pinch of chew during a
pesticide application?
20%
Yes
No
80%
Bad Habits also lead to Pesticide
Poisoning
Alarmingly, 25% of applicators surveyed ingested food
while applying pesticides without washing hands prior! This
increases exposure dramatically and may be extremely
dangerous. This may lead to acute or chronic pesticide
poisoning.

Have you eaten during the
mixing or application of
pesticides?
25%
Yes
No
75%
More bad habits….


70% of all applicators surveyed removed gloves at some
point in their career while repairing spray equipment.
9% never wore gloves to begin with.
Did you remove gloves while
repairing equipment?
9%
2%
19%
70%
Removed gloves while repairing equipment.
Wore gloves while repairing equipment.
Never wore gloves to begin with.
Gloves were not recommended on the product label.
Montana Poisonings: Why?



Bad Habits
– Eating while applying pesticides (25%)
– Chewing and smoking while applying pesticides
(20%)
Shortcuts
– Not wearing proper PPE (58%)
– Taking gloves off (79% of applicators)
Recurring focus on only Acute Toxicity
MSU PEP is trying to remind applicators to
focus on just letting history be our guide!
Pesticide Poisonings: When did
this begin?


A pesticide poisoning occurs when
chemicals intended to control a pest
affect non-target organisms such as
humans, wildlife, or bees.
Arsenic has been around for 1,000’s of
years. Evidence supports it’s discovery
as far back as ancient Egypt.
Tubocurarine has been found in
primitive weapons of primitive man
(>5,000 years old).

Perspective #1: 1939 – 1965
(What does not kill you makes you stronger!)

Silverbullet Pesticide
– 1939 Swiss Chemist Synthesized DDT
 Paul Humen Muller
DDT had non-target effects
Good Side of DDT?
-All but halted a 25%
mortality rate in
soldiers fighting in war
from TYPHUS with a
de-lousing program.
-Saved millions of lives
from malaria.
Perspective #2: 1965 – 1984
(Beware of who you trust, always be on the safe side!)
 Agent
White Compound
4:1 mixture of 2,4-D and
picloram
 Agent
Orange
1:1 mixture of 2,4-D and 2,4,5-T
Produces dioxins – carcinogen
The National Toxicology Program has classified TCDD to be
a human carcinogen, frequently associated with
soft-tissue sarcoma, Non-Hodgkin's lymphoma,
Hodgkin's disease and chronic lymphocytic leukemia (CLL).
1896 – 1985!
Chronic Toxicity

Long Term Exposure
– Many repeated low dose exposures





Definition
EPA mandates testing for chronic toxicity of:
– Active ingredients only
Usually on rats
This is very expensive
Chronic toxicity statements are placed on the
product label (carcinogen, mutagen, reproductive
damage, etc..)
1970’s - 1990’s: Perspective 3
Organophosphate and carbamate Era
 Hit
a climax in December 1984
Bhopal, India Disaster
 Methyl
isocyanate was an
intermediate chemical when
producing the product Sevin
 Pesticide cloud which
covered 25 square miles.
Toxicity
Union Carbide
Pesticide Manufacturing
Plant
 December 3rd, 1984
 8,000 initial dead
 15,000 more within 10 years
 500,000 suffer injuries
 water wells near the site show overall chemical
contamination to be 500 times higher than the
maximum limits recommended by the World
Health Organization.
 cancer, genetic defects (birth defects), and liver
and kidney damage.

27% of Montana applicators
indicated they did not clean up all
pesticide spills during their spray
career.
Perspective #4: Delisting of many
pesticide products from the 1990’s
to present day.
 Many
of our current pesticide
products have low acute toxicity.
 Have we learned from our mistakes.
Some of our “Safest” chemicals
 Chronic
Affects Evident
– Immune system problems
– Sores, Rashes
It happens.
Prostate Cancer
Associated With



Methyl bromide fumigant
Chlorinated pesticides (men over 50)
– Aldrin, chlordane, DDT, dieldrin, endrin, hexachlor,
toxophene
Five pesticides with men with a family history of
prostate cancer
– Insecticides: chlorpyrifos (Lorsban), coumaphos
(Co-Ral), fonofos (Dyfonate), permethrin (with
animal uses)
Respiratory Health
 Wheeze
(airways in lungs are
narrowed) associated with…
–Pesticides (Paraquat, parathion, malathion,
chlorpyrifos, atrazine, alachlor, EPTC)
Parkinsons Disease and Pesticide
Use
 Applicators
have up to twice the risk
of Parkinsons Disease
– Used pesticides more than 400 days in
their lifetime.
– Strongly associated with
paraquat use.
Personal Protective Equip.
(PPE)
 Good
News:
– Research shows PPE may reduce pesticide exposure by
90%
 Bad
News:
– Fabric or leather gloves usage
Are applicators protecting others
from pesticides?
Do you wear PPE that is required on the product label while applying
pesticides?
Wear required
PPE while
applying
pesticides
11%
42%
Do not wear
required PPE
while applying
pesticides
47%
While applying
pesticides, did
not know what
was on the
product label
Reading the product label can help
you!
*It can minimize risk towards yourself or
your family.
Pesticide Poisoning Summary

Acute Poisonings are still a problem
– Utah: 2 girls died in 2010
– Texas: 1 girl dies in 2007
– South Dakota: 1 girl died in 2000

Chronic Poisonings are common
–
–
–
–
–
High dose event early in ones life
Low dose exposures over time: no PPE
Improper storage of pesticides
Immune system susceptibility a problem
Genetic factors evident
Pesticide Use
 Is
Ok
 Read and Follow the Pesticide
Product Label
– Wear PPE
– Don’t drink it!
Contact Information
Contact your Local Extension Office
or the
MSU Pesticide Safety Education Program
Cecil Tharp, Pesticide Education Specialist
406-994-5067
ctharp@montana.edu
Web Address: www.pesticides.montana.edu