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Exposure to environmental contaminants. Hg in seafood Acute health effects ( Minimata ) Chronic health effects ( seafood (NY state)) Endocrine disruptors Effects on humans Effects on other animals Long Island Sound data. Heavy Metal Pollution in Water: Pb, As, Hg , Cd, others.
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Exposure to environmental contaminants • Hg in seafood • Acute health effects (Minimata) • Chronic health effects (seafood (NY state)) • Endocrine disruptors • Effects on humans • Effects on other animals • Long Island Sound data
‘Mad as a Hatter’ Did you know that the Mad Hatter from Alice’s Adventures in Wonderland is modeled after an occupational disease of the 18th and 19th centuries? In that era, hat makers were heavily exposed to mercury used in the preparation of felt. Consequently, many suffered brain damage and became psychotic, or “mad” (Katy, 1979). • Reference: Dennis Coon & John O. Mitterer (2007), Introduction to Psychology, 11th Edition, Wadsworth Cengage Learning
Hg Mercury • Human exposure through fish consumption • Neurotoxic; Neurodevelopmental effects • Crosses blood-brain, placental barriers • Bioaccumulation & biomagnification
MeHg Biomagnification Top predators and older, slow growing fish have high MeHg concentrations.
Minimata Disease, 1956 Over 2,000 victims
Source: acetaldehyde factory ~25-30 tons released
Mercury Exposure in New Yorkers • NYC HANES (Health and Nutrition Examination Survey) • 1/4 NYC adults have elevated blood Hg levels • 20-49 y old women, average blood mercury level 2.64 µg/L (3x the national average (0.83 µg/L) WHY?? • New Yorkers eat more fish • Fish consumed by New Yorkers is more contaminated with mercury
1/4 NYC adults have elevated blood Hg levels • 20-49 y old women, 2.64 µg/L (3x national average) • ¼ of these ≥ 5 µg/L • <5 µg/L for those who eat fish ≤3 times/week • >5 µg/L for those who eat fish ≥ 4 times/week • Higher-income adults have higher mercury levels; • highest income bracket 3.6 µg/L, • 2.4 µg/L for lowest income group • blood mercury higher among NYC Asian women (4.1 µg/L); • 45% have blood mercury levels ≥ 5 µg/L • Esp. foreign-born Chinese women; eat ~ 3 fish meals / week, compared to ~1 among average New Yorker • 1/4 Chinese New Yorkers eat fish 5+ times/week (McKelvey et al. 2007)
Significance of NYC HANES study • Important source of information about the health of a community • Information about local environment • Highlights need for improved education
FDA Seafood consumption guidelines “Women who might become pregnant, women who are pregnant, nursing mothers, and young children”. • “should include fish and shellfish in their diets. But . . . ” 2. “all fish and shellfish contain . . . mercury . . . those that contain higher levels . . . may harm an unborn baby or young child's developing nervous system”
Consumption guidelines 2 • Do not eat Shark, Swordfish, King Mackerel, or Tilefish • Eat up to 12 ounces (2 meals) a week of fish and shellfish that are lower in mercury (shrimp, canned light tuna, salmon, pollock, and catfish). • You may eat up to 6 ounces (one average meal) of albacore tuna per week. • Eat up to 6 ounces (1 meal) per week of fish you catch from local waters, but don't consume any other fish during that week. • Problem: Current recommendations based on fish Hg data from ~1991-2004.
Risks/Benefits of Fish consumption Estimated EPA/DHA and MeHg intake from one and two 3-ounce servings of seafood.
Other water pollutants • Nutrients (eutrophication) • POPs (persistent organic pollutants) • PCDDs, mirex, DDT • Pharmaceuticals • Endocrine disruptors
Silent Spring • Rachel Carson, 1962 • Drew national attention to eggshell thinning caused by DDT • Our Stolen Future, Theo Colborn, 1997
Endocrine Disrupting Compounds (EDCs) • Chemicals routinely used in industrial processes, agriculture and the production of a variety of domestic products which are able to bind to, and either activate or block endogenous steroid receptors • Widely distributed, environmentally stable and lipophilic • One of six high priority research issues, EPA 1996
Endocrine Disrupting Compounds (EDCs) • PCBs • PAHs • Surfactants • Plasticizers • Steroid hormones • Phytoestrogens
EDCs in the home • Phthalates • Food storage containers • Polyvinyl chloride (PVC) tubing/products (such as water pipes) • Flexible plastics, plastic bottles • Bisphenol A (BPA) • Metal cans of food and infant formula • Hard-plastic baby bottles • Sippy cups • Plastic bottles
Avoid exposure • How to Avoid Phthalates and BPA: • Do not microwave food/beverages in plastic • Do not microwave or heat plastic cling wraps • Do not place plastics in the dishwasher • If using hard polycarbonate plastics (water bottles/baby bottles/sippy cups), do not use for warm/hot liquids • Use safe alternatives such as glass or polyethylene plastic (symbol #1) • Avoid canned foods when possible (BPA may be used in can linings) • Look for labels on products that say “phthalate-free” or “BPA-free”
Environmental Relevance • Human • SevesoWomen’s Health Study (SWHS) • Exposure to relatively pure TCDD (1976) • Significant, dose-response increased risk of breast cancer • In males: • Cryptorchidism, hypospadias & decreased sperm counts
Environmental relevance • Reptile • Dicofol(DDT analog) spill by Tower Chemical Co. in Lake Apopka, Florida, 1980 • Compared to reference lakes, juvenile male alligators exhibited significantly: • Smaller penis size (24% average decrease) • Lower plasma testosterone levels (70% lower) • Baltic seal body burdens • Snails & TBT exposure
Environmental Relevance--Amphibian Hayes et al., 2002
Ovotestis Schmitt et al., 2005 Largemouth bass testes from Rio Grande
Long Island Sound • Watershed: 9 million inhabitants; 44 sewage treatment plants (STPs) (1 billion gallons day-1) • Historically used for shipping, fishing and waste disposal • Fluvial input: Connecticut, Housatonic, Quinnipiac, Thames
Water Quality Index dissolved inorganic nitrogen, dissolved inorganic phosphorus, chlorophyll a, water clarity, and dissolved oxygen
LI Sound • PCB concentrations in striped bass from the Sound declined from about 2.5 ppm to less than 0.5 ppm
Pathogens in LI Sound • Pathogens –disease causing bacteria and viruses • Primarily from stormwater runoff • animal waste, • human waste • from improperly maintained septic systems • illegal connections to ‘storm sewers’ • Older systems combine wastewater and storm water; wastewater transport to STP can overflow during high rainfall events