The effect of food consumption on the toxicokinetics of benzo(a)pyrene and 2,2′,4,4′,5,5′-hexachlorobiphenyl in

Abstract

The relative importance of water and ingested food as possible avenues of contaminant accumulation was examined. Mysis relicta was exposed to two representative non-polar contaminants: benzo(a)pyrene (BaP) and 2,2',4,4',5,5'-hexachlorobiphenyl (HCB). The accumulation was examined kinetically in the presence and absence of two food types, Daphnia pulex (water flea) and Tabellaria flocculosa (a diatom). The availability of either food enhanced HCB accumulation and reduced BaP accumulation. Feeding did not affect HCB elimination but enhanced BaP elimination. The BaP was eliminated primarily as metabolites. Essentially all of the elimination occurred via the fecal route for both compounds. The fraction of the accumulation via ingestion of contaminated food was greater when mysids fed on Daphnia than Tabellaria and was greater for HCB than BaP.

Tissue disposition of benzo[A]pyrene in blue mussel (Mytilus edulis) and effect of algal concentration on metabolism and depuration

“…There are examples in the literature where the depuration rate of HOCs was affected by the food concentration, but there are also examples where there was no effect. The depuration of hexachlorobiphenyl and B a P from Mysis relicta was studied with and without food given to the animals [8]. It was found that, while the depuration of B a P, which is readily metabolized, increased in the presence of food, the depuration of hexach‐lorobiphenyl, which is not extensively metabolized, was unaffected.…”

“…6). If this alternative is valid in explaining how depuration of HOCs is affected by food availability, the observed difference between the abovementioned crustaceans and Mytilus (the present study, [8–10]) might be due to a lower metabolic capacity in the mollusks [24].…”

“…The depuration rates of HOCs from invertebrates have in some cases been reported to be affected by the concentration of organic material, e.g., algal cells, in the water, but in other cases, no such effect was found [8–10]. The results are not necessarily contradictory since the investigations were made on different animal species and different HOCs.…”

Enantiomer Fractions of Organic Chlorinated Pesticides in Arctic Marine Ice Fauna, Zooplankton, and Benthos

“…In the Great Lakes, chiral PCBs had racemic signals in lower trophic levels (algae and bulk zooplankton), and a higher degree of nonracemity in higher trophic levels (mysids Mysis relicta) (15). An explanation for the nonracemic EF composition of chiral PCBs in mysids may be enantioselective biotransformation (15), although mysids have a low ability to biotransform other nonchiral PCBs (47), and the authors could not rule out the possibility that the animals obtained nonracemic residues by feeding on organic-rich suspended particles and sediment detritus (15). In the present study, biotransformation seems unlikely to have influenced the observed EFs not only due to low biotransformation ability in arctic marine invertebrates (their EFs and isomeric relative proportions highly resemble those in water; see, e.g., 9, 10), but also since samples of T. libellula, in which biotransformation should be comparable, differ in EFs depending on the habitat (Figure 2).…”

Chirality as an Environmental Forensics Tool

“…Invertebrates had been thought to have poor capability to biotransform many POPs, as shown by experiment [186][187][188]. This lack is likely from low CYP abundance and activity.…”