Distribution And Sources Of Polychlorinated Biphenyls And Organochlorine Pesticides In Multimedia In Various Functional Regions Of Shanghai

Polychlorinated Biphenyls (PCBs) and Organochlorined Pesticides (OCPs) are two kinds of typical Persistent Organic Pollutants (POPs). Due to their refractory to degradation, bioaccumulation and potential toxicity, PCBs and OCPs could pose serious threat to the ecological environment and human beings. For such concern, Stockholm Convention on POPs lists PCBs and OCPs both as Priority Pollutant for reduction or elimination. In order to implement the obligation effectively, China, as a party to the convention, need more investigation on POPs Pollution. As a building international metropolis and economic center of China, Shanghai should take lead in developing this field.Now, the systemic studies on distribution and characteristic of POPs in multimedia environment in different fuctional zones are less reported. Based on the study in our research group, this paper emphasizes on the distribution and transport characters of POPs in various functional regions of Shanghai. Sampling in different functional regions, POPs concentrations in atmosphere, soil and plant was detected by means of GC/ECD and GC/MS according to the USEPA method 8000 series under a strict QA/QC.Major results are as follows:(1) The contents of PCBs in atmosphere and soil were not high. Low chlorinated homologues of PCBs are dominant in atmosphere, while high chlorinated in soil. The OCPs contents in two kinds of environment media were also very low, mainly coming from residue after the pesticide forbidden. And HCHs and DDTs were occurred in different frequence among functional regions.(2) PCBs and OCPs characteristics of concentration and congeners in camphor leaves were similar to the results by SPMD when low concentrations.(3) The order of the PCBs concentrations in soil of different functional regions from high to low was business district, chemical industry zone, traffic zone, residential area and campus. And PCBs concentrations were at the same level in residential area and in campus, obviously lower than in the other functional regions.(4) The contents of PCBs and OCPs in soil shows the relation to the contents of TOC.(5) The correlation analysis in chemical industry zone indicates that there is no obvious relationship between DDTs and HCHs in multimedia environment. However, PCBs concentration in camphor leaves are well related with it in PM10. PCBs concentration around chlorine alkali factory are related with it around the coking plant in environment media, and the sequence of correlation coefficients was PM10>camphor leaves>soil. The sequence of correlation coefficients between PCBs and OCPs was soil>PM10>camphor leaves, and correlation coefficient in soil is as high as 0.89.And the following conclusion could be draw from the results of this study:(1) Functional regions could be divided into three types by their different sources ,â… (residential area and campus),â…¡(district and traffic zone) andâ…¢(chemical industry zone).(2) When air was slightly polluted by PCBs/OCPs, camphor leaves can be an effective environmental monitor which qualitatively reflects of PCBs/OCPs compositions.(3) PCBs pollution in air is the result of the combined influence of chemical production process, vehicle fuel leak and cooking fumes deposition. Different from chemical source, traffic source and fumes source are similar in congeners characteristics.(4) In chemical industry zone, DDTs and HCHs in multimedia environment come from different sources. Sedimentation of PM10 is the main reason for PCBs pollution in camphor leaves. Areas around chlorine alkali factory and coking plant came from the same PCBs source.(5) Compared with the informations in other areas, the pollution profile of PCBs and OCPs in Shanghai is in a low level, but there was a high risk in chemical industrial zone.