|
Organochlorine pesticides (OCPs). Polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) in the environment extensively, the prevalence of several classes of persistent toxic substances (PTS), due to environmentally persistent, bioaccumulative and toxic on human health and ecological environment has serious harm, has caused widespread concern in the community. OCPs, PCBs, etc. Although most of the pollutants in the 1980s after another in the domestic ban on the production, but studies show that these types of pollutants are still widely present in various environmental media, plants and animals, and the human body. Learn OCPs. PCBs and PAHs in the environment exists and pollution levels, environmental sources and analysis of its environmental risk assessment of target pollutants that can effectively predict POPs pollution trends in the development of relevant laws and regulations and environmental management basic data. This study collected the Yellow River Delta modern (modern course, Mc), the middle region (middle area, Ma) and the Yellow River (old course, Oc) three sampling region 22 wetland soil samples. By ultrasonic extraction, the use of GC or GC gas chromatography - mass spectrometry coupled with GC-MS analysis of the Yellow River Delta wetland technology three sampling areas of soil organic chlorine compounds (OCPs, PCBs) and polycyclic aromatic hydrocarbons (PAHs) content of the target compound, Based on basic physical and chemical properties of various materials and the use of history, analyze its distribution characteristics of different sampling areas. Source apportionment of the target compounds to determine the source of pollutants. Finally, the target substance risk assessment to determine the Yellow River Delta wetland environment of target pollutants in soil ecological risk. Field sampling and analysis showed that 19 kinds of organochlorine pesticides OCPs were detected in all samples, with heptachlor, chlordane, HCHs, DDTs based. The distribution of HCHs performance for the modern river (Mc) gt; Yellow River (Oc) gt; intermediate region (Ma), and the distribution of DDTs trend Oc gt; Mc gt; Ma, γ-chlordane, heptachlor and content are Mc gt; Ma gt; Oc. EPCBs average concentration level of Mc gt; Ma gt; Oc. EPAHs average concentration levels of the compounds Oc gt; Mc gt; Ma, while there are also the same for each component of PAHs distribution. More countries or regions at home and abroad in the soil OCP, PCBs and PAHs pollution levels compared to the Yellow River Delta wetland soil contamination levels of OCPs moderate, while slightly higher than domestic pollution levels of PCBs in some cities or regions, PAHs pollution levels are relatively light. Source analysis showed that the Yellow River Delta wetland soils HCHs may be mainly due to pesticide residues and long-range atmospheric transport, wildlife in the region there is a certain risk of exposure, but also on the input of the Bohai Sea in the presence of OCPs contribution. Chlordane and heptachlor sources and environmental risks worthy of further attention. PAHs mainly from coal, wood and oil burning. Overall, the Yellow River Delta wetland ecological environment of PAHs in soil risk is relatively low, but benzo [b] fluoranthene (BbF), benzo [k] fluoranthene (BkF), indeno [1,2,3 -cd] pyrene (Ind), benzo [g, h, i] perylene (BghiP) 4 are likely to have some PAHs of ecological risks.
|