Study Of Organic Chloride Pollutants In Natural Water Body By PFU Microbial Community

This thesis focused on microbial monitoring of organic chloride pollutants in natural water body by PFU(polyurethane foam unit) methods.We chosed Donghu lake and Ya'er Lake as our study areas.The organic chloride pollutants focused onα-HCH,β-HCH,γ-HCH,δ-HCH,HCB,pp'-DDE. The primary achievements are as follows:1,Using PFU as sampling material ,we detected organic chloride pollutants such as α-HCH,β-HCH,γ-HCH,δ-HCH,HCB,pp'-DDE in samples from idle sequential oxygenation ponds in Ya'er Lake in Wuhan by GC-ECD determination in October 2002. Experiment shows that the concentrations of organic chloride pollutants reduce from pond Ⅱ to pond Ⅴ sequentially,while those in pond Ⅰ are significantly low because of the disturbance of input water. The result corresponds with microbial community parameters by PFU method. PFU can be used as a sampling method for detection of organic chloride pollutants in natural water body and concentration variety of organic chloride pollutants in continuous water body. 2,By using microbial community PFU method, partitioning of organic chloride pollutants such as α-HCH,β-HCH,γ-HCH,δ-HCH,HCB,pp'-DDE in different phases of water in Donghu lake in Wuhan city has been studied in June 2003. Organic chloride pollutants such as α-HCH,β-HCH,γ-HCH,δ-HCH,HCB,pp'-DDE in PFU extrusion were determined by GC-ECD after pretreatment by sequential extraction method including cell-fixing,supersonic and digest procedures . A cell-fixing step was designed before solvent extraction to prevent the release of organic chloride pollutants in cells because of solvent toxicity. During cell-fixing and digest procedure, the number of microorganisms was detected microscopically in a simulation experiment of Tetrahymena thermophila BF5. The result shows that cell-fixing can prevent microorganisms bursting into fragment, and microorganisms will disappear thoroughly after digest. The detected results show that main part of organic chloride pollutants enriched in micro-organisms or strong adsorb on aqueous particles, including life and non-life detritus, minority pollutants slightly absorb on aqueous particles, and little in solution. As a sampling material to determine organic chloride pollutants in natural water body, PFU has the merit of high enrichment coefficient, convenience and economic. Because the particles adsorbed by PFU can be controlled below certain dimension, we suggest that PFU can be used as a sampling method for research of POPs in particles of natural water body.3,Biomonitoring by PFU method was taken in Yar Lake during first-stage organic chloride pollution treatment in October 2003. Organic chloride pollutants such as α-HCH,β-HCH,γ-HCH,δ-HCH,HCB,pp'-DDE in water and the parameters of microbial community were determined. During this investigation, 107 species of protozoa including 73 mastigophora species, 18 ciliata species and 16 sarcodina species were identified. The results showed that the water quality of pond Ⅱand Ⅲ have been obviously improved as a result of dredging up, and have no significant difference with pond Ⅳ and Ⅴ, which had ever been much better water quality before. But the concentrations of organic chloride pollutants in pond Ⅰwere much higher than in others because of the sediment removed into it. PFU biomonitoring method has the merit of high enrichment coefficient and lower limit of detection for organic chloride compounds, it was suggested that PFU can be used as a sampling method for research of organic chloride pollutants in natural water body.