Seasonal variations in the atmospheric concentrations of polybrominated diphenyl ethers in Kuwait

The study reports fortnightly atmospheric concentrations of PBDEs concomitantly measured at an urban and a remote location over a twelve-month period in Kuwait to examine seasonal variability and urban-rural concentration gradients. The annual mean (and range) of ∑PBDE concentrations was 32 (3-208) pgm^-3 at the remote site and 57 (0.3-445) pgm^-3 at the urban site. Although not statistically significant, the median (29pgm^-3) and mean (57pgm^-3) concentrations at the urban location were higher than those measured at the remote location (18 and 29pgm^-3 respectively), consistent with the view that urban centers are an important net source of these compounds to the environment. Although Clausius-Clapeyron plots showed statistically significant correlations (p<0.05) with temperature for low molecular weight congeners (BDEs 28, 47, 100), correlations with the σPBDE concentrations were not significant at both urban and remote sites. The seasonal variations in σPBDE concentrations were not markedly different at the urban location, but the median summer σPBDE concentration at the remote location was significantly higher than winter median σPBDE concentrations. The absence in seasonality at the urban location may be due to ongoing primary emissions in urban areas.