A density functional theory study of a series of symmetric dibenzylideneacetone analogues as potential chemical UV-filters.

The aim of this research was to provide valuable insights on symmetrical α,β-unsaturated ketones as potential chemical ultraviolet (UV) filters from experimental data and theoretical aspects. Towards this end, density functional theory (DFT/B3LYP) calculations on a series of symmetrical α,β-unsaturated ketones, ()-1,5-bis[4-(R)phenyl]penta-1,4-diene-3-one (R = methylthio, ; R = dimethylamino, ; R = ethyl, ), were performed to determine the effect of different electron-donating substituents on their stability when exposed to solar UV radiation. Their molecular structures, and UV-visible, infrared (IR) and NMR (H and C) spectra were theoretically obtained from their optimized geometries with the B3LYP/6-311++ G (d, p) basis set and were compared with the experimental results.

Organochlorine pesticides and polybrominated diphenyl ethers in giant African snail from the Niger Delta, Nigeria: Implications for dietary exposure and health risk assessment.

The concentrations of organochlorine pesticides (OCPs) and polybrominated diphenyl ethers (PBDEs) were evaluated in snails from different locations in the Niger Delta of Nigeria to provide data about their sources and possible risk to humans from the consumption of snails. The OCP and PBDE concentrations in snail samples ranged from 0.31 to 12.

Organochlorine pesticide contamination of soils and dust from an urban environment in the Niger Delta of Nigeria.

The concentrations, sources, and risk of twenty organochlorine pesticides (OCPs) in soils and dusts from a typical urban setting in the Niger Delta of Nigeria were examined. The Σ20 OCP concentrations (ng g) varied from 4.49 to 150 with an average value of 32.

Safety evaluation of organochlorine pesticides and polybrominated diphenyl ethers in imported canned fish in Nigeria.

Organochlorine pesticide (OCP) and polybrominated diphenyl ether (PBDE) concentrations were measured in thirty popular brands of imported canned fish (mackerel, sardines, and tuna) in Nigeria to ascertain potential threats to humans arising from their consumption. The Σ20 OCP concentrations in mackerel ranged from 0.47 to 7.

Polybrominated diphenyl ether contamination in sediments from rivers in the western Niger Delta of Nigeria.

This study investigated the concentrations of 39 polybrominated diphenyl ether (PBDE) congeners in sediments from three rivers in the western Niger Delta of Nigeria that have been affected by pollution from urbanization and industrial activities. The Σ39 PBDE concentrations in sediments from these rivers ranged from 0.29 to 95.