Bioaccumulation of polycyclic aromatic compounds: 2. Modeling bioaccumulation in marine organisms chronically exposed to dispersed oil

Abstract

Within the frame of a large environmental study, we report on a research program that investigated the potential for bioaccumulation and subsequent effect responses in several marine organisms exposed to chronic levels of dispersed crude oil. Body burden can be estimated from kinetic parameters (rate constants for uptake and elimination), and appropriate body burden-effect relationships may improve assessments of environmental risks or the potential for such outcomes following chronic discharges at sea. We conducted a series of experiments in a flow-through system to describe the bioaccumulation kinetics of polycyclic aromatic hydrocarbons (PAH) at low concentrations of dispersed crude oils. Mussels (Mytilus edulis) and juvenile turbot (Scophthalmus maximus) were exposed for periods ranging from 8 to 21 d. Postexposure, the organisms were kept for a period of 9 to 10 d in running seawater to study elimination processes. Rate constants of uptake (k1) and elimination (k2) of the PAHs during and following exposure were calculated using a first-order kinetic model that assumed a decrease of the substances in the environment over time. The estimated bioconcentration factor was calculated from the ratio of k1/k2. The kinetic parameters of two-, three-, and four-ring PAHs in mussel and fish are compared with estimates based on hydrophobicity alone, expressed by the octanol-water partition coefficient, Kow (partitioning theory). A combination of reduced bioavailability of PAHs from oil droplets and degradation processes of PAHs in body tissues seems to explain discrepancies between kinetic rates based on Kow and actual kinetic rates measured in fish. Mussels showed a pattern more in compliance with the partitioning theory.

A closer look at bioaccumulation of petroleum hydrocarbon mixtures in aquatic worms

“…29,2010respectively). Uptake rate constants for the KVHB sediment were lower, but demonstrated a similar relationship with boiling point, as has also been reported in the literature for PAHs and polychlorinated alkanes [18][19][20]. Note however that for this sediment, the concentrations of the fraction C 28 -C 34 did not exceed the detection limit.…”

“…The overlying water was gently aerated with activated carbon-purified air. Uptake kinetics were determined for HIJG and KVHB sediment, by measuring TPH bioaccumulation after 3,5,8,11,14,19,22,27,35, and 49 d of exposure. Twenty eight-day bioaccumulation was subsequently determined for all sediments.…”

Comparison of the uptake of polycyclic aromatic hydrocarbons and organochlorine pesticides by semipermeable membrane devices and caged fish (Carassius carassius) in Taihu Lake, China

“…To avoid many of these limitations, in situ passive sampling devices, such as lipid-containing semipermeable membrane devices (SPMDs), have been developed [1] and used extensively in recent years [2][3][4]. The SPMDs are designed to sample the truly dissolved fraction by the thermodynamically driven process of solute partitioning [1,5] between the aqueous and lipid phases. In this respect, SPMDs mimic the bioconcentration process of HOCs in aquatic organisms [1,6].…”

Bioaccumulation of phenanthrene and benzo[a]pyrene in Calanus finmarchicus

“…Many 20 authors have found a linear relationship between log K ow and log bioconcentration factor 21 (BCF) (Hawker and Connell, 1986;Mackay, 1982;Veith et al, 1979) indicating that 22 bioaccumulation is linked to hydrophobicity for a given PAH compound. However, several 23 studies also show that lower bioavailability and higher metabolism of the heavier compounds 24 may modify this linear relationship and the accumulation of the heavier compounds may be 25 lower than expected (Baussant et al, 2001b;Southworth et al, 1980;Spacie et al, 1983;van 26 Hattum et al, 1998). 27 28 Hence the resulting effect on an organism exposed to crude oil may vary depending on the 29 combination of an organism's ability to bioaccumulate, metabolize and excrete these 30 compounds.…”