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Bioaccumulation & Bioaccumulation & BiomagnificationBiomagnification
ofofToxicantsToxicants
Pat Ellsworth, ITEPPat Ellsworth, ITEP
Robert K. HallRobert K. HallU.S. EPA Region IXU.S. EPA Region IX
& & Sherry GlickSherry Glick
U.S. EPA U.S. EPA Office of Pesticide Programs
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Bioaccumulation & Bioaccumulation & Biomagnification:Biomagnification: IntroductionIntroduction
• Bioaccumulation Bioaccumulation – Pollutant concentration increase from Pollutant concentration increase from
environment to first organism in food environment to first organism in food chain chain
• Biomagnification Biomagnification – Pollutant concentration increase from Pollutant concentration increase from
one food chain link to another one food chain link to another
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Bioaccumulation & Bioaccumulation & Biomagnification:Biomagnification: Introduction Introduction
(cont.)(cont.)
• For biomagnification to occur, For biomagnification to occur, pollutant must be pollutant must be – Long-lived Long-lived – Mobile Mobile – Soluble in fats Soluble in fats – Biologically active Biologically active
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Persistent Bioaccumulative Persistent Bioaccumulative Toxic Toxic (PBT)(PBT)
Chemical ProgramChemical Program• Program designed to identify, measure and Program designed to identify, measure and
prevent further risks to human health and prevent further risks to human health and environment from existing and future exposureenvironment from existing and future exposure– Persistent Persistent – BioaccumulativeBioaccumulative– Toxic (PBT) pollutantsToxic (PBT) pollutants
• These pollutants pose risksThese pollutants pose risks– Toxic Toxic – Persist in ecosystems Persist in ecosystems – Accumulate up food chainAccumulate up food chain
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PBT Chemical Program PBT Chemical Program (cont.)(cont.)
• What makes a PBT? What makes a PBT? – Travels long distances Travels long distances
– Transfers rather easily among Transfers rather easily among air, water, landair, water, land
– Lingers for generations (long-Lingers for generations (long-lived in environment)lived in environment)
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PBTs: What are they?PBTs: What are they?
• Substances that resist environmental Substances that resist environmental (i.e., (i.e., hydrolyzation, photolyzation)hydrolyzation, photolyzation) and biological and biological (e.g., microbial activity)(e.g., microbial activity) degradation degradation
• Can cycle through several environmental Can cycle through several environmental media media (e.g., water, soils, plants, animals, (e.g., water, soils, plants, animals, people)people)
• Long residence time in environment – can Long residence time in environment – can travel long distancestravel long distances
• Toxic Toxic (acute, chronic)(acute, chronic) to plants, animals, to plants, animals, humanshumans
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PBTs: Persistent PBTs: Persistent Organic Pollutants (POPS)Organic Pollutants (POPS)
– Chemical substances Chemical substances (combustion (combustion
byproducts or manufactured)byproducts or manufactured) resistant to resistant to
chemical breakdown chemical breakdown (i.e., persist)(i.e., persist)
– Stored in body Stored in body (i.e., bioaccumulate)(i.e., bioaccumulate)
– Cause adverse effects: acute, chronic, multi-Cause adverse effects: acute, chronic, multi-
generational generational (genetic – alter gene (genetic – alter gene
expression)expression)
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PBTs of Key ConcernPBTs of Key Concern
• POPs POPs (industrial processes, pesticides, by-products (industrial processes, pesticides, by-products of combustion)of combustion) – Aldrin/Dieldrin, Chlordane, Mirex, Toxaphene, Aldrin/Dieldrin, Chlordane, Mirex, Toxaphene,
DDT (+DDD+DDE), hexachlorobenzeneDDT (+DDD+DDE), hexachlorobenzene– PCBs, Dioxins/FuransPCBs, Dioxins/Furans
• Trace metals Trace metals (natural sources; human-caused (natural sources; human-caused emissions)emissions) – MercuryMercury– LeadLead– CadmiumCadmium– SeleniumSelenium
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Effects of PBT ExposureEffects of PBT Exposure
• POPs exposurePOPs exposure– Endocrine disruptionEndocrine disruption– CancerCancer– Birth defects, multigenerational Birth defects, multigenerational
reproductive challengesreproductive challenges– Reduced immune functionReduced immune function– NeurologicalNeurological
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Effects of PBT Exposure Effects of PBT Exposure (cont.)(cont.)
• Trace-metal exposureTrace-metal exposure– LeadLead (learning and development) (learning and development)– CadmiumCadmium (renal failure (liver, kidney), (renal failure (liver, kidney),
itai-itai disease)itai-itai disease)– SeleniumSelenium (teratogenic - birth defects) (teratogenic - birth defects)– MercuryMercury (Neurological effects (learning (Neurological effects (learning
and development, acute dose – and development, acute dose – teratogenic)teratogenic)
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PBTs: Heavy MetalsPBTs: Heavy Metals
– Natural elements released by nature Natural elements released by nature (e.g., (e.g., volcanoes)volcanoes) and humans and humans (e.g., mining, (e.g., mining, manufacturing)manufacturing)
– Some are essential Some are essential (e.g., zinc, manganese, (e.g., zinc, manganese, selenium)selenium), some are not , some are not (mercury, lead, cadmium)(mercury, lead, cadmium)
– Stored in muscle, organs and bone. Not essential Stored in muscle, organs and bone. Not essential (Pb, Cd – Itai-Itai/osteo degeneration),(Pb, Cd – Itai-Itai/osteo degeneration), replace Ca in replace Ca in bonebone
– All metals toxic in high doses. Some essential trace All metals toxic in high doses. Some essential trace metals toxic in extremely low doses metals toxic in extremely low doses (e.g., zinc, (e.g., zinc, selenium, iron)selenium, iron)
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How are we exposed?How are we exposed?
• Direct personal exposure to airborne PBTs from Direct personal exposure to airborne PBTs from local sourceslocal sources– Diesel exhaustDiesel exhaust– Cigarette smokeCigarette smoke– Cooking oils, product outgassing in indoor airCooking oils, product outgassing in indoor air– Cultural activities (e.g., cadmium in riparian plants)Cultural activities (e.g., cadmium in riparian plants)
• Exposure to long-range transported PBTs Exposure to long-range transported PBTs through foodthrough food– Global pollutionGlobal pollution– PBTs enter and cycle through environmental media, PBTs enter and cycle through environmental media,
bioaccumulate in wildlifebioaccumulate in wildlife
13Mercury Pollution: Integration and Synthesis, Copyright Lewis Publishers, an imprint of CRC press.
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From: Inuit Tapiriit Kanatami website
FOOD CHAIN:
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Trace-Metal SolubilityTrace-Metal Solubility
Substances Solubility Product
Substance Solubility Product
Ba(OH)2 2.55 x 10-4 FeS 1.57 x 10-19
SrSO4 3.44 x 10-7 Cu(OH)2 4.80 x 10-20
BaSO4 1.08 x 10-10 Pb(OH)2 1.40 x 10-20
Mn(OH)2 2.04 x 10-13 PbS 8.81 x 10-29
MnS 4.55 x 10-14 Al(OH) 3 3.00 x 10-34
Cd(OH) 2 7.20 x 10-15 CuS 1.28 x 10-36
Zn(OH)2 7.68 x 10-17 Fe(OH)3 2.67 x 10-39
Fe(OH)2 4.79x10-17 Cu2S 2.24 x 10-48
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What can you do?What can you do?
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National InventoriesNational Inventories
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Conclusion:Benefits and Risks of a Traditional Diet
Risks
• Accidents – hunting/fishing
• Contaminants
Benefits
•Health – reduced obesity, diabetes, heart disease
•Nutrition
•Taste
•Social-cultural value
•Cost
•Children’s education
From Dr. Harriet Kuhnlein, CINE