Bioaccumulation Lecture Notes PDF

BIOACCUMULATION PIM LEONARDS A-LIFE: Amsterdam Institute for Life and Environment 1 Outline ▪ Bioaccumulation Bioconcentration > Physical-chemical properties vs. BCF Biomagnification Trophic magnification 22 3 Bioaccumulation...

BIOACCUMULATION PIM LEONARDS A-LIFE: Amsterdam Institute for Life and Environment 1 Outline ▪ Bioaccumulation Bioconcentration > Physical-chemical properties vs. BCF Biomagnification Trophic magnification 22 3 Bioaccumulation of DDT 4 Bioaccumulation ▪ Describes the transfer and accumulation of a chemical from the environment into an organism ▪ The chemical concentration in the organism achieves a level that exceeds that in the environment (e.g. water) 55 Bioaccumulation Mechanism Water-respiring organisms Gill uptake/elimination Biotransformation Dietary Growth Uptake Lier Dietary uptake Fecal excretion 6 Bioaccumulation Mechanism Air-breathing organism Air inhalation/exhalation Biotransformation Growth Dietary uptake Fecal excretion Milk excretion Urine excretion Biotransformation Growth Egg Dietary uptake excretion Fecal excretion Air inhalation/exhalation Urine excretion 7 Definitions 8 Bioaccumulation definitions water A A A B B [C1] [C2] [C3] Bioconcentration: A Biomagnification: B if Cn > Cn-1 Bioaccumulation: A + B 9 Bioconcentration (BCF) Concentration in organism higher than in its surrounding environment Environment is main route of uptake (e.g. water) Corg Bioconcentration Factor (BCF) = Caq Corg concentration in organism (mg/kg) Caq concentration in water (aqueous phase) (mg/L) Determined in laboratory at steady state 10 Biomagnification (BMF) Concentration in organism is higher than that in its food, when food is main route of uptake Corg Biomagnification Factor (BMF) = Cf Caq Concentration in water Cf Concentration in food Best determined under laboratory conditions Field data, chemical uptake by all exposure routes 11 Bioaccumulation (BAF) The extent of chemical bioaccumulation is usually expressed as Bioaccumulation Factor (BAF) Accumulation of a chemical in organism both from food and the environment (Caq) under field conditions Corg from the field Bioaccumulation Factor (BAF) = Caq from the field 12 Factors related to bioaccumulation ▪ Fat content ▪ Age ▪ Sex ▪ Weight: body mass of organism relative to the surface area across which exchange with water phase takes place ▪ Difference in uptake route ▪ Metabolic activity (biotransformation) Lipid content vs BCF of 1,2,4-trichlorobenzene in different fish species (Geyer et al., 1985). 13 Age and sex dependent DDT accumulation in dolphins After Abarnou et al. (1986) 14 14 Bioconcentration (BCF) 15 Bioconcentration Factor (BCF) Chemical uptake in aquatic organism Corg Expressed on wet weight or lipid weight (mg/kg) BCF = C BCF L/Kg aq Expressed on volume basis (mg/L) EU legislation: BCF ≥ 2000 -> bioaccumulative BCF ≥ 5000 -> very bioaccumulative 5-6-2024 Titel en de naam van de Spreker 16 16 Bioconcentration test ▪ OECD 305 BCF test protocol ▪ Fish test ▪ 28 days ▪ Exposure of two concentrations of the chemical ▪ Uptake phase ▪ Concentration of chemical followed in fish and water Followed by depuration phase in clean water Exposure (uptake) Depuration 17 17 Accumulation and elimination kinetics One-compartment model Kw Corg Caq Water Ke Organism Corg concentration in organisms (mg/kg) Caq concentration in aqueous phase (mg/L) kw uptake rate constant (L/kg·day) ke elimination rate constant (1/day) t time (day) 18 Uptake and depuration of endosulfan sulphate Steady-state Exposure phase Depuration phase (clean water) Hoang et al, 2011, Chemosphere 84, 538-543 19 19 Calculation of BCF 20 Examples BCF curves 21 Multicompartment model Elimination 22 Physical-chemical parameters related to bioaccumulation 23 23 Physico-chemical properties partitioning coefficients ▪ Kow: Octanol-water-partitioning coefficient (water- lipid) Lipophilicity ▪ Koa: Octanol-air-partitioning coefficient (biota–air) Partitioning biota and air ▪ Acid dissociation constant pKa (acid–H+) Release of H+ or OH– (polarity) 24 Relevance Kow ▪ Kow is a measure for Lipophilicity (hydrophobicity) ▪ Compounds with a high Kow pass cell membranes relatively easily accumulate in fatty tissues Low Kow High Kow High Kow stored in specific organ 25 Prediction of BCF, sorption and toxicity Hexachlorobenzene Aceton Log Kow - 5.73 Log Kow = -0.24 Octanol Octanol Water Water Bioconcentration Soil sorption Lethal concentration factor (LC50) BCF Kow Kow Kow 26 Lipophilicity (Kow) indicative of bioaccumulation potential of chemicals (BCF) 27 For very high lipophilic chemicals: BCF no longer correlated with Kow 28  BCF vs LogKow -2 0 2 4 6 8 10 LogKow Arnot and Gobas, 2006, Environ Rev 141 29 Octanol-air partition coefficient (KOA) Koa is a measure for retention of a compound in air- breathing organisms Partitioning of chemical between n-octanol and air Coctanol Koa = Cair Compounds with a high Koa pass respiratory surface relatively easily accumulate in air-breathing organisms 30 Bioavailability bound chemical to particles, not bioavailable Dissolved chemical, bioavailable Fraction of the total concentration, in a specific medium, that can be absorbed by an organisms Bioavailable fraction: Fraction of a chemical “freely” dissolved in the water phase Total water concentrations: chemical bound to particles + free dissolved fraction 31 31 Calculated BAF on total and dissolved water concentrations Water concentration Pyrene Total concentration Dissolved concentration Cl Cl PCB153 Cl Cl Cl Cl 2 4 6 8 Log BAF (field) Titel en de naam van de Spreker 32 Biomagnification (BMF) B B [C1] [C2] [C3] 33 33 34 Biomagnification 34 Biomagnification kinetics (from Sijm, 1992) 35 35 Kow vs BMF From Fisk et al. (1998) 36 Key factors in BMF ▪ Concentration in food and organisms ▪ Lipid or protein content of diet and organisms ▪ Biotransformation ▪ Most reliable BMF is determined in the laboratory ▪ BMF calculation in field situation: Prey-predator relationships Diet composition 37 37 Trophic magnification (TMF) 38  Piscivoreous Pelagic and benthic food web bird Common tern Algae Pelagic phytoplankton Mysids Herring Sandeel Zooplankton Fish Seabass SPM Whiting Fish Benthic Sculpin Cockles algae Sole Flounder Worms Plaice Crabs Piscivorous Goby Shrimps Benthic fish microalgae Benthic fish Bottom Sediment invertebrates Primary producers First level predators Grazers and filter feeders Second level predators 39 Trophic magnification factor (TMF) approach TMF equals the slope Log concentration TMF>1 Trophic level (TL) TMF = 10^regression coefficient 40 TMF example: PCB 153 4.0 Log Concentration Fish PCB 153 (ng/g 3.5 eating Pelagic lipid weight) 3.0 birds Benthic 2.5 2.0 Fish 1.5 Low trophic 1.0 organisms 0.5 0.0 0.0 2.0 4.0 6.0 Trophic level (15N isotope) 41 41  Trophic transfer PCB and pyrene Pelagic Benthic PCBs Pyrene Log concentrations (ng/g lw) 4.0 5.0 4.0 3.0 3.0 2.0 2.0 TMF 2.5 1.0 1.0 0.0 0.0 0.0 2.0 4.0 6.0 0.0 2.0 4.0 6.0 Trophic level Trophic level Biotransformation important factor 42 42 Kow, BCF, TMF logKow logBCF TMF PCB52 5.84 6.5 1.4 HCB 5.86 4.5 1.5 Pyrene 6.11 4.1 0.3 BDE47 6.00 4.2 2.2 a-HBCD 5.62 4.4 1.6 y-HBCD 5.62 4.4 0.3 PFOS 6.28 3.6 2.6 43 43 Summary key issues (I) BAF, BCF, BMF, TMF Factors influencing bioaccumulation Relationship bioaccumulation with physical-chemical properties 44 Summary key issues (II) Biotransformation (metabolisation) is a key factor in bioaccumulation Persistent lipophilic chemicals with low biotransformation can undergo biomagnification Water-soluble and readily biodegradable chemicals cause usually less problems with bioaccumulation 45  Kahoot.it Pin: 7511373 Fate/bioaccumulation questions 46