Pharmaceuticals, DDT and human health. BettinaGenthe

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1 Pharmaceuticals, DDT and human health BettinaGenthe

2 Extent of the problem 3.6 Million people in South Africa have no access to safe water and 16 million have no access to hygienic sanitation Babies, young children, the elderly and people that experience immune deficiencies, are particularly vulnerable when exposed to microbiologically polluted water.

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4 Microbial contamination linked to sources of effluent discharge and water pollution can have an effect on the health of farmers and farm workers PJ Oberholster

5 CSIR 2007 Slide 5

6 Water Resource Crisis Of 850 municipal WWTW in South Africa only 3,6% achieved green drop status 55% of wastewater treatment facilities require drastic improvement transporting and treating 7600Ml of water daily. department had committed R30bn on upgrading water resources

7 Benefits of DDT Malaria is one of top killers. Reduction in malaria incidence and case fatality rates resulted from indoor DDT spraying From 150 to 50 per 100,000

8 DDT in the environment DDT gets into the atmosphere as a result of spraying DDT and its metabolites also enter the atmosphere through the volatilization of residues in soil and surface water Deposited on land and in surface water (dry and wet). The process of volatilization and deposition may be repeated many times, and results in what has been referred to as a global distillation from warm source areas to cold polar regions. As a result, DDT and its metabolites are transported to the Arctic and Antarctic regions where they are found in the air, sediment, and snow and accumulate in biota.

9 Malaria

10 DDT re-introduced in SA Synthetic pyrethroids replace DDT

11 Malaria and climate change The projected climate change scenarios for South Africa indicate an extension of malaria-prone areas predicted that malaria area could >2X in next 50 years, 7.8 million people could be at risk, of whom 5.2 million did not previously live in malaria areas

12 Health Effects DDT used to prevent malaria Neurotoxic effects associated with a decrease in verbal, memory, and quantitative and perceptual performance skills among preschoolers. Classified as probable human carcinogen non-occupational exposure to DDT is associated with impaired semen in men. Endocrine system effects: Oestrogen mimicking and anti-androgenic results in uro-genital defects

13 Health effects continued In animals, the liver appears to be one of the primary targets of DDT toxicity. Acute, subchronic, and chronic oral administration of DDT has been shown to cause dose-related mild-to-severe hepatic effects High levels affect nervous system excitability tremors and seizures DDE can reduce lactation duration in women and increase chance of premature baby in numerous animal studies.

14 Exposure to DDT Direct photolysis of DDT and DDD is very slow in aquatic systems, with estimated half-lives of >150 years Exposure to DDT could occur to populations that consume fish from DDT-contaminated marine environments. DDT and derivatives found in water and food

15 Risk Calculations CancerRisk LADD LADD = lifetime average daily dose ToxicRisk ADD RfD ADD= Average daily dose and RfD = Reference dose

16 Exposure Parameters used in risk assessment and risk calculations EXPOSURE INFORMATION UNITS VALUES Body weight (Bw) Kilogram (kg) Life expectancy (Lft) Days (d) 70 (70 x 365) Exposure duration (ED) Days (d) 365 per year Drinking water intake rate (IR) Dermal exposure rate 65 Litres (L) 1.2 Hours (h) 0.2 h per day based on cm 2 skin surface area Vegetable exposure rate kg Daily 40% of 0.2 kg per event Fish ingestion rate kg Daily 0.15kg per event per 365 days per year # # Based on an averaging factor of 0.15kg fish eaten per day but with conversion of chemical content in fat to amount of fat eaten. This is based on freshwater fish having 1% fat content.

17 9.0E-04 Cancer risks based on average total DDT concs 8.0E E E E E E E E E+00 drinking w ater 1.2L ingestion of vegetablesw atering inhalation of indoor air inhalation from outdoor air soil or dust ingestion fish ingestion sw imming or bathing dermal absorption Control average Test average WHO

18 drinking water 1.2L vegetable watering indoor air outdoor air soil or dust ingestion fish ingestion dermal absorption Hazard indices for toxic effects expected from exposure to total DDT Control averag Control max Test average Test max

19 Qualitative Health Risk Assessment Fish increased intersex, apoptosis, reduced sperm mobility Reduced sperm count Human semen quality impaired quality where DDT spraying occurred - Mean lipid adjusted p,p-dde values 215ug/g. - Previous studies potent anti-androgenic effects were observed at 63.6ug/g lipid adjust DDE concentration Bio-assays > 50% samples detected oestrogenicity Babies examined at birth (n =7145 ) found 55.6/1000 uro-genital defects p = 0.028

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21 Frequency of urogential abnormalities in DDT sprayed vs unsprayed villages Micropenis P= Cryptorchidism Hypospadias Chordee sprayed unsprayed Phimosis Penile cyst Any UGS Ambiguous genitalia

22 Conclusions of DDT in environment Carcinogenic risks - Fish - Vegetable - Dermal absorption Toxic effects Endocrine effects

23 Endocrine disruptors ELAND TDS EDC link CSIR 2007 Slide 23 Bornman, 2004

24 Pharmaceuticals analysed contrast media Iopamidol (used for medical imaging) Iopromid Ibuprofen (anti-inflammatory and acidics analgesic) Diclofenac (anti-inflammatory) Antibiotics Clarithromycin Erythromycin Sulfamethoxazole Trimethoprim Carbamazepine (antiepileptics and antiepileptics mood stabilizer) Dihydrocarbamazepine Dihydrodihydroxycarbamazepin Temazepam (hypnotic agent) psychoactive Codein (opiate analgesic, antitussive, and anti-diaorrheal) drugs Diazepam (Valium ) Benzoylegconine (1 0 metabolite of CSIR 2010 Slide 24 cocaine)

25 Concentration [ng/l] Results: Pharmaceutical removal Pharmaceuticals S1 S2 S3 S4 S5 S SMX Sulphamethoxazole CMZ Carbamazepine DHC Dihydrodihydroxy- Carbamazepine IOP Iopromide IOH Iohexol IBU Ibuprofen DIC Diclofenac SMX CMZ DHC IOP IOH IBU DIC All Sampling-Points: Traces of psychoactive Drugs < 50 ng/l (Temazepam, Codeine, Oxazepam, Diazepam) LOQ [ng/l] CSIR 2010 Slide 25

26 Conclusions Pesticides (DDT) found in many water samples Pharmaceuticals also found in majority of water samples tested carbamazepine, ibuprofen and sulphamethoxazole fortunately in low concentrations in final water but highlights the need for monitoring Similar results found in Sweden Need effective water treatment And wastewater treatment CSIR 2010 Slide 26