Kyoungphile Nam

Phenanthrene was rapidly and extensively mineralized by a bacterium in the presence of glass or polystyrene beads with no pores, silica beads with 2.5−15 nm pores, 3-aminopropyl-bonded silica beads with 6-nm pores, and diatomite beads with 5.4 μm pores. These beads sorbed 10−99% of the compound in 15 h, but 48−100% of the sorbed hydrocarbon was desorbed in 240 h. Although little phenanthrene was desorbed from octadecyl-bonded silica beads with 6-nm pores, the hydrocarbon was rapidly and extensiv

A study was conducted to determine the relationship between organic matter content of soil and the availability of aged phenanthrene. Phenanthrene was aged for 200 days in sterile samples of dissimilar soils, soils treated with H 2 O 2 to reduce the content of organic matter, and sand. Sequestration as measured by the extent of mineralization of phenanthrene by an added bacterium was appreciable in samples with >2.0% organic C, and the bioavailability of the hydrocarbon declined with time of agi

The combined toxic effects of Cd and Pb in the presence of different concentrations of Ca(2+) were predicted using the biotic ligand model (BLM), with the parameters derived from the Cd-only and Pb-only toxicity data. The BLM-based toxic unit (TU) approach and the proposed BLM-based f(mix) approach were used for prediction. The predicted mixture toxic effects using the BLM-based f(mix) approach were closer to the observed mixture effects (root mean square error [RMSE] = 9.7 at 25 mM Ca(2+) ) tha