Polybrominated Diphenyl Ether Leachability from Biosolids and Their Partitioning Characteristics in the Leachate

摘要

Biosolids are commonly applied to agricultural soils. A laboratory investigation was carried out to determine polybrominated diphenyl ether (PBDE) congener profiles in biosolids and leachability by water. In addition, PBDE fractionation in water and suspended solids of different sizes was examined to determine the potential for enhanced mobility of these contaminants within soils. The leachates from glass column experiments were passed through a series of filters, and the filtrates and retained particles analyzed for PBDEs. PBDEs were found to sorb on solid particles suspended in the leachate, allowing PBDEs to be present at concentrations exceeding their aqueous solubilities. The filtration process indicated that PBDEs are associated with fine and ultrafinernparticles. Filters of different pore sizes provide a better indication of PBDE levels in the leachate compared to not filtering or using a single filter. PBDEs concentrations were much higher on ultrafine than on fine particles, due to the greater surface area and higher organic content of the former.