The Perspective of Wastewater
Management
Dr. Homero Silva
Professor in Public Health, Environment and Climate Change
School of Public Health and Health Technology
UTECH
We live in an environmental arrogance
Because of our
Environmental ignorance due to our
environmental tolerance
• Real values
– Jamaican BOD5
– Real BOD5
• Effective Treatment
• Treatment based in Epidemiological Context
Typical Medium Domestic Sewage
BOD5 with outliers
95% Confidence interval
(199 mg/l, 233 mg/l)
BOD5 without outliers
95% Confidence interval
(194mg/l ,226 mg/l)
Total Nitrogen with outliers
95% Confidence interval
(37.1 mg/l, 43.8 mg/l)
Total Nitrogen without outliers
95% Confidence interval
(35.4 mg/l, 40.6 mg/l)
Jamaica Total BOD5 Values
With Outliers
Number of Samples
Mean
Std. Error of Mean
Median
Mode
Std. Deviation
Variance
Skewness
Std. Error of
Skewness
Kurtosis
Without Outliers
285
213,79
8,589
173,70
103
145,003
283
209,70
8,147
172,80
103
137,052
21025,917
18783,119
,959
,695
,144
,145
,773
-,471
Jamaica Total Nitrogen Values
275
Without Outliers
275
Mean
40,479
38,025
Std. Error of Mean
1,7113
1,3134
Median
36,700
36,400
52,8
52,8
Std. Deviation
28,6357
21,7805
Variance
820,006
474,389
Skewness
2,404
,649
Std. Error of Skewness
,146
,147
10,738
,210
With Outliers
Number of Samples
Mode
Kurtosis
The Real BOD5
• The test was developed around 1910 in England,
• To predict the ‘oxygen sag’ when sewage is
discharged into the river and how long it would
take the river to ‘self purify’.
• ‘Oxygen sag’ is the lowering of dissolved oxygen
in the river over a certain distance, downstreamsof
the discharge of sewage and ‘self purification’ is
achieved when the dissolved oxygen level is again
the same, as it was before the sewage was
discharged in the river.
• The BOD test measures how much
oxygen is used by bacteria, until all such
activity cedes.
• it is the summation of two oxygen usages,
one of heterotrophic bacteria feeding on
carbonaceous (fecal) waste or C-BOD and
the second one that of autotrophic bacteria
feeding on nitrogenous (urine and protein)
waste or N-BOD.
• Autotrophic bacteria only contributes to the
test reading after 6 to 8 days
• The use of oxygen by autotrophic bacteria
can be calculated by using the faster TKN
(Total Kjeldahl Nitrogen) test, it became
common, in order to save time, to use the 5day reading of the test (BOD5), representing
part of the oxygen use by the heterotrophic
bacteria, in combination with the TKN test
representing the oxygen used by the
autotrophic bacteria.
Real Total BOD
• Total BOD= C-BOD (1.5 x BOD5) + NBOD (4.6 x TKN).
• Total BOD= 1.5 x 210 + 4.6 x 38
• Total BOD= 497.4
Effective Treatment
• Are discharge standard limits sufficient to
protect health?
Effective Treatment
• BOD5 vs Heavy metals and Endocrine
disruptors
Treatment based in
Epidemiological Context
Epidemiological-Demographic and
Socio-economic transitions
Top five leading causes of death in Jamaica 1945-2004
1945
1982
1996
2004
Tuberculosis
Cerebrovascular
Disease
Cerebrovascular
Disease
Cerebrovascular
Disease
Heart Disease
Heart Disease
Diabetes Mellitus
Diabetes Mellitus
Nephritis
Malignant
Neoplasm
Ischaemic Heart
Disease
Ischemic Heart Disease
Syphilis
Hypertension
Hypertensive
Diseases
Hypertensive Diseases
Pneumonia
Influenza
Diabetes Mellitus Homicide/Assault
Gastroenteritis
Source: Chronic Disease in the Caribbean: Jamaica Case Study
Other Heart Disease
Accidents and Injuries(Accidents, poisoning
and violence)*
21
Epidemiological-Demographic and
Socio-economic transitions
Top five leading causes of death in Jamaica 1945-2004
1945
1982
1996
2004
Tuberculosis
Cerebrovascular
Disease
Cerebrovascular
Disease
Cerebrovascular
Disease
Heart Disease
Heart Disease
Diabetes Mellitus
Diabetes Mellitus
Nephritis
Malignant
Neoplasm
Ischaemic Heart
Disease
IschemicObesity
Heart Disease
Syphilis
Hypertension
Hypertensive
Diseases
Hypertensive Diseases
Pneumonia
Influenza
Diabetes Mellitus Homicide/Assault
Gastroenteritis
Source: Chronic Disease in the Caribbean: Jamaica Case Study
Other Heart Disease
Accidents and Injuries(Accidents, poisoning
and violence)*
22
Present Health Conditions and Threats
•
•
•
•
•
•
•
•
Chronic Diseases↑
Obesity ↑
Mental Health ↑
Violence ↑
Sedentarism ↑
Junk Food ↑
Energy Consumption per capita ↑
Environmental Pollution ↑
From Homo sapiens to Homo sedens
24
Estimated DALY’s per 100,000 population, 2004
Jamaica
Communicable, maternal, perinatal and
nutritional conditions
3,893
NCDs
10,250
Injuries
2,170
Total
16,314
Country profile of Environmental Burden of
Disease (Jamaica)
DALYs Comparison for Total Jamaica
Population
• NCDs
• Diarrheas
10,250 Years Lost
280 Years Lost
• Where we need to look at in Environmental
Health?
Attention Deficit Hyperactivity Disorder (ADHD) in
Jamaican Children
• 12% of 5-6 yr olds with externalising behaviour
disorders (Samms-Vughan, 2005);
• None of the Children had received assistance
• Prevalence likely to be higher in inner-city areas
• Jamaican and Thailand Children highest rate
ADHD in the world (Achenbach, 2007)
Manganese and Anemia
• Excess manganese interferes with the absorption of
dietary iron. Long-term exposure to excess levels may
result in iron-deficiency anemia.
• Excess manganese may be a problem for infants with
low iron status, as this is known to increase the
absorption of manganese.
• Mena et al. (1969) found that anemic subjects absorbed
7.5% of ingested Mn, whereas normal subjects absorbed
3%.
• IDA patients had a mean blood Mn concentration of 2.05
± 0.44 μg/dl, which was higher than controls. (Kim 2005)
• Calcium deficiency increases manganese absorption
(See Bottled Water Slide).
Nitrates in Drinking Water and health
•
•
•
•
•
•
Diabetes incidence was positively associated with raised mean nitrate levels
with a standardized incidence ratio of 115 in zones with greater than 14.85
mg.1-1 (chi2 = 26.81, 1 df, p < 0.001). (Parslow, 1997)
A research in United States suggested a positive correlation between lowlevel nitrate exposure through drinking water and type 1 diabetes at nitrate
levels < 10 mg/L (Kostraba, 1992).
Nitrite may also react in the stomach with amines and amides to form Nnitroso compounds, which have genotoxic properties (van Maanen, 1992;
Vermeer, 1998) and may also play a causative role in the initiation of gastric
cancer (Gangolli, 1994).
A role of N-nitroso compounds in the etiology of cancer of the esophagus
and nasopharynx (Magee, 1989) as well as a linkage between the
occurrence of non-Hodgkin lymphoma and nitrate exposure have been
suggested (Ward, 1995).
New targets for nitrate exposure were recently defined, including thyroid
and pancreas. Nitrate exposure can lead to hypertrophy of the thyroid due
to inhibition of uptake of iodine by the thyroid (Van Maanen, 1994)
Germans found this effect at 22.5 mg/l Nitrate as NO3. (Horing, 1988)
Nitrates in Drinking Water and health
• From the above information the NWC wells in the metropolitan area
should be evaluated, specially those that are above 22.5 mg/l as NO3 .
Table below presents information on Nitrate concentration of some of the
wells.
Table 1. Major anions in the well waters of the Kingston Basin.
Well Name
Rockfort
Devon House
Forrest Hills
Cl234
30
82
NO35.2
20.5
24.9
NO3- as N
1.17
4.63
5.62
HCO-3
301
357
240
SO4
76
62
27
Chancery Hall
23
23.4
5.29
255
22.7
Havendale
22
4.7
1.06
245
20
Cavaliers
52
15.3
3.46
259
76
Up Park Camp
43
48.5
10.96
258
87.2
Montgomery Corner
13
56.6
12.79
96.4
59.6
Rennock Lodge
176
20.2
4.56
218
105
Beverly Hills
17.2
5.6
1.27
111
104
Forest Hills, Beverly Hills, Montgomery Corner, Cavaliers, and Up Park Camp are not being
Used by NWC, because of high NO3
Endocrine Disruptors and Obesity
• Diet and physical activity are undoubtedly key causal factors
related to the increase in obesity.
• There is growing interest in the possibility that endocrine
disrupting chemicals (EDCs) may affect obesity-related
pathways by altering cell signaling involved in weight and lipid
homeostasis*
• The idea that changes in the diet and physical activity cannot
account for all of the increase in obesity is strengthened by
evidence showing that most energy expenditure is devoted to
basal metabolism and other physiological processes.
* Homeostasis is the property of a system in which variables are regulated so that internal conditions remain stable
and relatively constant.
Perturbation of Thyroid Function
• Thyroid function is key to maintenance of basal
metabolism.
• A number of EDCs, including phthalates, BPA, and
PBDEs, are suspected thyroid disruptors and
seem to have the net effect of reducing
circulating thyroid levels (Zoeller, 2007).
• While much early work on endocrine disruption
focused on reproductive and carcinogenic
effects, the hypothesis that chemicals may affect
weight homeostasis emerged more recently
from different lines of research.
Leptin Hormone
• Where adipose tissue was once considered an inert
storage depot, the discovery of the hormone leptin in
the 1990s led to the recognition that adipose itself is
an active endocrine organ, secreting various hormones
and adipokines and expressing many receptors (Ahima
and Flier, 2000; Newbold, 2009).
• Evidence was also mounting in support of the concept
of “the developmental basis of adult disease,” which
suggests that exposures in utero could lead to chronic
diseases later in life (Heindel, 2003; Oken and Gillman,
2003).
In utero exposures
• It may be particularly important due to sensitivity during development.
• Certain environmental agents or stressors during critical windows of
development can lead to obesity later in life.
• The “thrifty phenotype” hypothesis postulates that an undernourished
fetal environment causes permanent metabolic programming aimed at
conserving nutrients, leaving the individual susceptible to obesity and
other metabolic disorders when faced with the unrestricted diet
typical of many developed countries (Gluckman, 2008).
• This programming likely involves epigenetic alterations in the
methylation patterns and histone structure that help determine gene
expression, alterations which may lead to obesity due to permanent
changes in the function of specific tissues (Heindel and vom Saal,
2009).
• Maternal malnutrition, smoking, diabetes, and chronic stress have all
been consistently associated with childhood obesity in epidemiologic
studies, and provide evidence for this phenomenon (Huang, 2007).
In utero exposures
• The average newborn has 287 chemicals in the
umbilical cord blood, 217 of which are neurotoxic.
• The chemicals these infants are exposed to include
pesticides, phthalates, bisphenol A, flame retardants,
and heavy metals such as mercury, lead, and arsenic.
• 20% of POPs are transferred to the fetus
• Breastfeeding releases 8.76 kg fat per year
• A breast fed baby receives 10% of the cumulative
dosage of a 50 years person
• Dioxine concentration of a baby is 1.7 times the
mother concentration
PCB, HCB and DDE Serum Concentrations Breast Fed versus
Formula milk 6 weeks y 6 months
2.5
Breast Fed 6 weeks
2
Serum Concentration, µ/l
Breast Fed 6 months
Formula Milk 6 wweks
Formula Milk 6 months
1.5
1
0.5
0
PCB 138
PCB 153
PCB 180
Sigma PCB
Pollutant Type
HCB A
DDE, A
A "striking" relationship: POPs and
diabetes
• A 2006 study found "striking" relationships between six
POPs and diabetes in U.S. adults exposed to normal
levels of POPs.
• The higher the levels of these POPs, the higher the
prevalence of diabetes.
• In the highest exposure group, the risk of diabetes was
37.7 times higher than in the people with the lowest
levels of exposure.
• Surprisingly, this study found that obesity
did not increase the risk of type 2 diabetes if those
people had very low levels of POPs in their
bodies.
Treatment based in Epidemiological Context
• Increase in water reuse for green areas
irrigation
– Milking wastewater from sewage
– Removing bacteria and Endocrine disruptors and
leave nutrients
The End