Factors Affecting the Bioavailability of Polychlorinated Biphenyls (PCBs) in Soils

摘要

Bioassay was conducted with Aroclor 1254 (polychlorinated biphenyls (PCBs)) applied to untreated (1.4% organic matter (OM)) and peroxide-treated (0.2% OM) Lakeland sand at 0-200 ppm. Growth of redroot pigweed (Amaranthus retroflexus L.) appeared to decline greater in the treated soil at the highest PCB level. Soil was treated with 200 ppm PCB and received peaty OM and montmorillonite clay at rates of 0-10% total soil weight. OM was more effective than clay in reducing PCB toxicity in pigweed. Carbon-14 (C-14) labeled PCB was decreasing adsorbed, in the order of OM, clay, untreated sand, and treated sand, with OM content being a more important influence on adsorption than surface area. Treating soil containing 1000 ppm PCB with no growth reductions. Qualitative differences in PCB uptake appeared to occur between plant species. Activated carbon treatment reduced C-14 PCB uptake 89-100%. A triazine-resistant pigweed translocated more C-14 label to its foliage than redroot pigweed, in soil containing 100 ppm PCB and added C-14 PCB.