Role of participate organic matter in decreasing accumulation of polynuclear aromatic hydrocarbons byDaphnia magna

Accumulation of benzoa]pyrene (BaP) and anthracene (A) byDaphnia magna in the presence of suspended yeast cells was analyzed using multicompartment models. The rate coefficient for uptake of polynuclear aromatic hydrocarbon (PAH) due to ingestion of yeast cells laden with sorbed chemical was only 3 to 15% of the rate coefficient for uptake of dissolved PAH. Uptake and accumulation of BaP was reduced 97% due to sorption of PAH to naturally occurring organic matter (humic acids). Accumulation of hydrophobic chemicals in aqueous systems appears to depend on the amount of chemical in solution and on the amount of chemical sorbed to particles entering the food chain. Chemicals sorbed to suspended organic matter, including dissolved or colloidal organic matter, have greatly reduced availability.Research sponsored by the Office of Health and Environmental Research, U.S. Department of Energy, under contract W-7405eng-26 with Union Carbide Corp. Publication No. 2127, Environmental Sciences Division, ORNLBy acceptance of this article, the publisher or recipient acknowledges the U.S. Government's right to retain a nonexclusive, royalty-free license in and to any copyright covering the article