Bioaccumulation Flashcards
Defiition: tendency for toxicants to accumulate w/in the bodies of exposed organisms
Bioaccumulation
Definition: accumul of contaminants from water ONLY
bioconcentration
(bioconc factor) BCF = __ / __
BCF=Cf / Cw
Definition: toxicants accum’d both from water AND from diet
bioaccumulation
T or F: there is a tendency for concentrations in biota to decrease as you go higher in the food chain
False; they INCREASE as you move up food chain
The propencity for non-polar organic compounds to bind to org carbon is measured as ___
Koc
What are 3 factors that cause variation in Koc?
Humic & fulvic acids, partially degraded biological material, soot carbon
Koc is directly proportional to ___
Kow
Bioconcentration is modeled by the _____-compartment bucket model. What is the accumulation formula?
Single; amt of water accumulating = k1/k2
Bioaccum is modeled by the ____-compartment bucket model. What is the formula?
multi; water accum = k1+k2/k3+k4+k5
Single compartment model = Hydrophobicity or Physiological model?
Hydrophobicity
Mutli-compartment model = Hydrophobicity or Physiological model?
Physiological
The primary basis for both the hydrophobicity and physiological models is that _____ organic chem’s dissolve in and accum in ______
non-polar; lipids
Soluble contimates generally DO or DO NOT bioconcentrate?
DO NOT
In the hydroph. (bioconc.) model, uptake is limited by _______, and ______ is negligible.
diffusion across gills; metabolsim
T or F, the hydroph/bioconc. model works well over a narrow range.
False; only over a broad range
Name the 5 main factors that affect both models
1) lipid content
2) biotransform’n/metabolism
3) intra- and inter-species variation & animal size
4) env cnditions (temp, ph, salinity)
5) Bioavailability (only a fraction of contam may be available for take-up)
______ fish at _____ temperatures achieved equilibrium faster
smaller; higher
Log BCF = (____ * _____) - ___
Log BCF = (0.85 * Log Kow) - 0.7
Why does the bioconcentration factor NOT always work?
Metabolization of compounds is not taken into acct
What does POP stand for and what does it pertain to (what waters?)?
POP = Persistent Organic Pollutants; Great Lakes
The Gobas Food Chain uses what model?
The steady state model; assumption of equil.
What are the 3 parts of toxicokinetics?
Uptake, elimination, bioaccum
What does BMF stand for?
BioMagnification Factor
BMF is the result of ____ uptake that is not _____. Only with high Kow chemicals.
Dietary; eliminated
BMF = __/(K2 + Ke + __ + __)…. if you work this equ’n out for each trophic level w/ chemicals of values of Kow, what is your result
BMF = kd/(k2 + ke + km + kg); Food Chain Multipliers (FCM)
BAF = ____ * ____
BAF = BCF * FCM
