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1 What is in the Water and What are the Risks? Bryan W. Brooks, Ph.D. Associate Professor and Director Environmental Health Science Program Texas Innovative Water 2010, San Antonio
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2 What is in the Water and What are the Risks? Today: Focus on Pharmaceuticals and Endocrine Active Compounds Bryan W. Brooks, Ph.D. Associate Professor and Director Environmental Health Science Program Texas Innovative Water 2010, San Antonio
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3 We’ve come a long way… “The flow below Dallas for many miles does not impress one as being that of a river. A stench from its inky surface putrescent with the oxidizing processes to which the shadows of the overreaching trees add stygian blackness and the suggestion of some mythological river of death. With this burden of filth the purifying agencies of the stream are prostrated; it lodges against obstruction in the stream and rots, becoming hatcheries for mosquitoes and malaria. A thing of beauty is thus transformed into one of hideous danger.” Texas Department of Health 1924
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4 So, What is Risk? Risk – the probability of an adverse outcome Risk assessment – the scientific characterization of potential adverse effects resulting from human and ecological exposures to chemicals or other stressors ExposureToxicity RISK
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5 PARACELSUS (1493-1541) “All substances are poisons: there is none which is not a poison. The right dose differentiates a poison and a remedy” Toxicity is not Risk
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6 So, What is Risk? Risk – the probability of an adverse outcome Risk assessment – the scientific characterization of potential adverse effects resulting from human and ecological exposures to chemicals or other stressors Risk management – the process by which policy actions to deal with the hazards identified in the risk assessment process are selected
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7 So, What is Risk? Some common risks – You have a one in a million chance of dying by: - being struck by lightning, or - eating 40 tablespoons of peanut butter, or - having one chest x-ray in any given year The chance of dying in a car accident is 12,000 times greater than the above risks… …but I drove to San Antonio
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8 So, What is Risk? Scientists ask questions – Are people/wildlife being exposed to chemicals? What is the magnitude, duration, and frequency of exposure? Are adverse human health / ecological outcomes possible? Citizens ask questions, too – Is the exposure voluntary, is it familiar? Does it have relevance to me, can I control it? What are the severity and immediacy of the effects?
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9 So, What is Risk? Scientists ask questions – Are people/wildlife being exposed to chemicals? What is the magnitude, duration, and frequency of exposure? Are adverse human health / ecological outcomes possible? Citizens ask questions, too – Is the exposure voluntary, is it familiar? Does it have relevance to me, can I control it? What are the severity and immediacy of the effects?
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10 So, What is Risk? Scientists ask questions – Are people/wildlife being exposed to chemicals? What is the magnitude, duration, and frequency of exposure? Are adverse human health / ecological outcomes possible? Citizens ask questions, too – Is the exposure voluntary, is it familiar? Does it have relevance to me, can I control it? What are the severity and immediacy of the effects?
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11 “AP Probe Finds Drugs in Drinking Water” 9 March 2008 Contaminants of “Emerging” Concern?
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12 Contaminants of “Emerging” Concern? Pharmaceuticals and Personal Care Products (PPCPs) Heart medications, Antidepressants, Antibiotics, Contraceptives, Antimicrobials, Fragrances, etc Endocrine Disrupting/Modulating Compounds (EDCs) Surfactants, Plasticizers, Pesticides, Steroids, etc PPCPs EDCs 17α-ethinyl estradiol
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13 Why are pharmaceuticals/EDCs studied? SPE-GC-MSMS SPE-LC-MSMS We now have the ability to measure chemicals at VERY LOW levels…. ….so we can now report trace concentrations of drugs, etc at below part per trillion levels… ….but are the risks acceptable?
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14 What about Human Health? What if a human adult consumes 50 ng/L (parts per trillion) of Drug X in their drinking water? - A human therapeutic dose of Drug X = 50 mg. - The person would need to consume 1,000,000 L to receive a therapeutic dose of Drug X. - If the person consumed 5 L per day, then it would take 548 years to receive one dose of Drug X.
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15 What about Human Health? Under the Safe Drinking Water Act, US EPA identifies substances for potential regulation (e.g., MCLs). Several pharmaceuticals were recently placed on US EPA’s Contaminant Candidate List 3. Of these pharmaceuticals, most were endocrine active substances, another was an antibiotic. http://www.epa.gov/safewater/ccl/ccl3.html
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16 Brooks et al. 2005 ET&C Texas Fish can Accumulate Drugs in Edible Tissues…. ….should I stop eating the fish? What about drugs in the fish I catch?
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17 National Pilot Study of PPCPs in Fish Tissue for US EPA Ramirez et al. 2009. ET&C
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18 What if a human adult consumes a fish fillet with 50 ng/g (parts per billion) of sertraline, the drug in the antidepressant Zoloft? - One tablet of sertraline HCl = 50 mg sertraline. - A consumption rate of 0.286 kg/meal is used (EPA). - A person would consume 14.3 μg in one fish meal. - A person would need to consume 3,496.5 meals to receive one therapeutic dose of sertraline. - If a person consumed 1 fish meal per day (from the contaminated site), then it would take almost 10 years to get one daily dose of sertraline.
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19 The Public Remains Interested… National Geographic April 2010
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20 So, What about Aquatic Life?
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21 Ecological Issues Associated with Effluent Water Quality Point source “effluent” water quality evaluated by whole effluent toxicity tests, chemistry, pathogens WQC, prospective assessments use using same organisms Biological integrity evaluated by “ambient” toxicity tests, biotic surveys, biomarkers algae + + Daphnia fish www.cefas.co.uk
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22 Occurrence Fate Effects Current Knowledge Exposure Effects Where we are now… Where we are going… CECs in Surface Waters
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23 Evidence of aquatic life impacts in the field? “There are several cases where strong evidence supports a causal linkage between exposure and effect. Two examples discussed … are organotin-mediated imposex in marine snails and feminization of sewage effluent-exposed male fish.” “Caged fish and laboratory-based exposures confirm that sewage effluent is responsible for the observed increases in vitellogenin (WHO 2002) and reproductive failure (Martinovic et al. 2007).” Hotckiss et al. 2008. Toxicological Sciences
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24 The Type of Chronic Response Matters.... 90 th centile ACR (79.5) for aquatic toxicants (Raimondo et al 2007) Berninger and Brooks. 2010. Toxicology Letters Chronic Effects of Some Drugs are much Lower than Traditional Contaminants…
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25 Importance of Exposure and Internal Dose Fick et al 2010. ES&T Exposure in the Field = Internal dose/Human Cmax ?
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26 Fick et al 2010. ES&T Zeillinger et al 2009. ETC Ex. Levonorgesterel, a synthetic progestin Exposure in the Field + Sub-ppt Effects in the Lab Importance of Exposure and Internal Dose
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27 Langdon et al 2010 Integrated Environmental Assessment & Management Biosolids receiving more attention…
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28 Aquatic Life Criteria for Contaminants of Emerging Concern –http://www.epa.gov/waterscience/criteria/library/sab-emergingconcerns.pdf White Paper submitted to EPA Science Advisory Board (SAB) in July 2008 –received comment from SAB in December 2008 –http://yosemite.epa.gov/sab/sabproduct.nsf/E37FB6980DCDD9B5852575320 05F6F2C/$File/EPA-SAB-09-007-unsigned.pdf Recent EPA Activities
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29 Senate Bill 1757 Project SB-1757 passed in Texas 81 st Legislative Session, 2009. The Texas Commission on Environmental Quality (TCEQ) shall study and make recommendations regarding the methods to be used by consumers, health care providers, and others for disposing of unused pharmaceuticals so that they do not enter a wastewater system. Report due to legislature December 1, 2010.
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30 Brooks et al. 2009 Environmental Toxicology and Chemistry Selecting Compounds for Management / Monitoring Prioritization of Ecological Hazard/Risk Aquatic and Terrestrial Fate and Exposure: Experimental and Modeling Ecologically Relevant Traditional and Alternative Measures of Effect Environmental Monitoring and Risk Management
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31 So, Where Are We Going? Lessons learned from pharmaceuticals/EDCs –Urban water resources is the new normal - public connection Risk Assessment must inform Risk Management –Biological effects Treatment technologies Exposure to pharmaceuticals and EDCs in drinking water appear to present very low relative risk More studies are needed for other chemicals (e.g., disinfection byproducts, flame retardants), and mixtures Adverse effects on aquatic life are possible, particularly in Texas. Many regulatory agencies around the globe are presently prioritizing risks and chemicals for more study
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32 SETAC Globe 10(4): 4. Some more of my thoughts… Brooks et al 2009. ETC. OPEN ACCESS! Thank You!
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