Polycyclic aromatic hydrocarbons (PAHs) were measured in 342 daily PM10 samples collected in four seasons at a site in Bengbu, China. This study was a qualitative and quantitative investigation of the emission sources of atmospheric PAHs in Bengbu and the spatial distribution of regional PAH sources in PM10 samples. The annual concentrations of the 16 EPA priority PAHs ranged from 1.45 to 62.16 ng/m3, with an annual mean of 7.63 ± 7.38 ng/m3. The seasonal trends during the year were: winter (6.13–62.16 ng/m3, median = 14.99 ng/m3) > autumn (2.01–18.78 ng/m3, median = 4.90 ng/m3) > spring (1.45–19.34 ng/m3, median = 3.32 ng/m3) > summer (1.57–4.27 ng/m3, median = 2.12 ng/m3). The PAHs over the year were dominated by medium-molecular-weight PAHs (39.81%), followed by high-molecular-weight PAHs (35.77%), and low-molecular-weight PAHs (24.42%). The diagnostic ratio method and positive matrix factorization revealed that the PAH sources in Bengbu in spring and summer were industrial emissions, coal and biomass combustion, and traffic emissions; while the sources in autumn and winter were coal and biomass combustion and traffic emissions. According to a backward trajectory clustering analysis and potential source contribution function analysis, Bengbu City was mainly affected by pollution from the northern and northwestern regions in spring, autumn, and winter, while it was more affected by the coastal monsoon in summer. The PAH pollution in Bengbu was most severe in spring, autumn, and winter, and the health risk to the population was also most severe at that time. The health risk to adult males (3.35 × 10−4) was greater than the risk to adult females (3.14 × 10−4), and the health risk to adults was greater than the risk to children (2.52 × 10−4).
This study investigated the occurrence and distribution of pesticides in surface water (lakes, major rivers and tributaries) and potential discharge sources (fish ponds, livestock and poultry farms, and sewage treatment plants) in Wujin District (northwest of Taihu Lake), Jiangsu province, China. An analytical liquid chromatography-tandem mass spectrometry method was developed for 38 pesticides, which was applied in the monitoring of 240 surface water samples and 76 potential discharge source samples. Eleven insecticides and five fungicides with temporal and spatial variation were detected in surface water. The total pesticide concentrations in surface water in different seasons were as follows: March > August > June > November. The two most polluting and widespread pesticides were carbendazim (maximum concentration 508 ng L −1 , detection rate 100%) and imidacloprid (maximum concentration 438 ng L −1 , detection rate 88%). Gehu Lake (S46) and Sanshangang River (S12) were seriously polluted water bodies. Seven insecticides and four fungicides were detected in the potential discharge sources; and their composition changed significantly with the seasons. The concentrations of detected organophosphorus pesticides and neonicotinoids ( e.g. acetamiprid in March and dichlorvos in November) in a few non-agricultural planting sources were far greater than those detected in surface water, and hence a few fish ponds, livestock and poultry farms, and sewage treatment plants might be the potential discharge sources of pesticides in the surrounding surface water. The estimated input flux of the studied pesticides from upstream rivers to Taihu Lake was 141.95 kg a −1 . Furthermore, more attention should be paid to the medium or high aquatic ecotoxicological risk presented by the levels of organophosphorus pesticides, carbamates, and benzimidazoles.
危险品化学品经营许可证（带存储）