Monitoring and risk assessment of polychlorinated biphenyls (PCBs) in agricultural soil from two industrialized areas

For monitoring and risk assessment, levels and distributions of I (29) pound PCBs in paddy soil samples collected from Gwangyang (10 sites) and Ulsan (20 sites), heavily industrialized cities in Korea, were investigated using high-resolution gas chromatography/high-resolution mass spectrometry. Overall, total concentrations of I (29) pound PCBs in Gwangyang (216.4-978.6 pg g(-1) dw) and Ulsan (273.8-1824.1 pg g(-1) dw) were higher than those (106.6-222.6 pg g(-1) dw) in agricultural soil from Anseong in Korea. The TEQ (toxic equivalency) values from Gwangyang (0.06-0.40 ng TEQ kg(-1) dw) and Ulsan (0.06-0.22 ng TEQ kg(-1) dw) were higher than those (0.04-0.11 ng TEQ kg(-1) dw) in Anseong but lower than the WHO threshold level (20 ng TEQ kg(-1)). However, one of the most toxic congeners, PCB 126, gave the highest concentration, possibly posing a risk to the biota. Seven indicator PCB congeners contributed to 50-80% of the total concentration of I (29) pound PCBs, indicating the 7 PCBs can be used as valuable indicators for monitoring. The principal component analysis and cluster analysis for the homologue profiles of PCBs indicated that all the samples from both cities had the similar PCB contamination patterns, and the major sources of the PCB contamination were most likely from the usage of Aroclor 1254 than those of Aroclors 1242 and 1260. These PCB technical mixtures were possibly significantly used by various industries including iron and steel industries in Gwangyang and petrochemical and shipbuilding industries in Ulsan.clos

Historical profiles of Polycyclic Aromatic Hydrocarbons (PAHs) in marine sediment cores from north-west Spain

The northwest coast of Spain is characterized by an irregular coastline rich in marine life and with the highest mussel production in Europe. Taking this into account, the characterization of the pollution levels and the sources involved appear necessary. Not only were parent Polycyclic Aromatic Hydrocarbons (PAHs) analysed but also their alkylated homologues. In total, 35 compounds were analyzed in 5 sediment cores. Sediments were collected using a box core dredge and extracted by (Pressurized Liquid Extraction) whilst the quantification of PAHs was performed using gas chromatography coupled to mass spectrometry (GC–MS). The total concentration detected varied from 49.6 to 2489 ng g-1 dry weight (d.w.) of which parent PAHs ranged from 44.5 to 2254 ng g-1 d.w. and alkylated PAHs varied from 5.04 to 317 ng g-1 d.w. Temporal and spatial evolution were outlined and pollution sources were identified along with a possible correlation between this pollution and local history and industry. Most of the PAHs from the superficial samples have a biomass and coal combustion profile, and some specific, localized events are reflected in the total PAH concentration evolution. Moreover, the study of the deepest layers of the sampled cores provides a baseline to develop background concentration values that will help in future sediment quality assessment.Versión del editor1,927