Spatial and seasonal distribution of organochlorine pesticides in the sediments of the Yangtze Estuary.

The spatial and seasonal distribution of organochlorine pesticides (OCPs) in the sediments of the Yangtze Estuary was investigated. The total concentration of 19 OCPs (∑OCPs), including α-HCH, β-HCH, γ-HCH, δ-HCH, o, p'-DDE, p, p'-DDE, o, p'-DDD, p, p'-DDD, o, p'-DDT, p, p'-DDT, heptachlor, aldrin, heptachlor epoxide (Isomer B, Isomer A), endosulfan I, dieldrin, endrin, endosulfan II and methoxychlor, in the surface sediments ranged from 0.4 to 82.

Prediction of nitrobenzene toxicity to the algae (Scenedesmus obliguus) by quantitative structure-toxicity relationship (QSTR) models with quantum chemical descriptors.

In this study, Quantitative structure-toxicity relationship (QSTR) models were developed to predict the toxicity of nitrobenzene to the algae (Scenedesmus obliguus). Quantum chemical descriptors computed by PM3 Hamiltonian were used as predictor variables. The cross-validated Q²(cum) value for the optimal QSTR models is 0.

Toxicological assessment of TiO2 nanoparticles by recombinant Escherichia coli bacteria.

Rapid and efficient methods to assess nanoparticle toxicity are desired in current research. Here we showed that Escherichia coli labeled by green fluorescent protein can be a good model bacterium for assessing acute toxicity of TiO(2) (about 50% inhibition ratios after 135 min exposure). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) revealed that TiO(2) nanoparticles (NPs) can influence certain protein expression in the recombinant bacterium, and the obvious effects in repressed expression and elevated expression were observed in 30/40, 10/20 μg mL(-1) treated cells, respectively.