Residual Characteristics And Regularity Of PCBs In Chinese Youth’s Serum

As a very typical kind of Persistent Organic Pollutants, PCBs was widely producedand used in1940s-60s.Because of its persistence,long distance migration ability,biological enrichment ability and biological toxicity,it was gradually stop using in manycountries in the1970s. Today after it’s stop using for almost40years,PCBs still has alarge number of residual worldwide. It enters human body gradually through breathing,eating, drinking and skin contact, eventually harm human health such as teratogeniccancer, liver and kidney damage function by enrich in fat tissue. Human serum levels ofPCBs is an important index to measure the human PCBs exposure levels. With thechinese youth as the objective, this study discusses the residual features and rules oftypical PCBs in human serum from different regions,provides basis data for the humanPCBs exposure levels and control strategy research.The youth’s blood sample was collected from all over the country. This nationwidelarge-scale research is base on134young people whose age17-20. With PCBS as targetcompounds, we optimize the efficient serum sample solid phase extraction purificationmethods,establish gas chromatography mass spectrometry (GC-MS) instrument analysismethod for84PCBs congener. The method recovery, blank experimental data meetstrict quality control and quality assurance standards.The analysis of PCBs composition and distribution characteristics indicates that theaverage Σ84PCBs concentration is234.8ng/g lw. There’s no significant genderdifference, but the concentration of city samples is significantly higher than the ruralsamples. The main congener in serum is low chlorinated PCBS primarily, theconcentration of high chlorinated PCBS and the frequency is relatively low. The serumaverage ΣDL-PCBs concentration14.83ng/g lw. There’s no significant genderdifference of ΣDL-PCBs, but the concentration of ΣDL-PCBs in city samples issignificantly higher than the rural samples. The average value of a total TEQ of all thesamples is37.45pgTEQ/g lw. The average total seven indicator PCBs concentration is39.14ng/g lw. There’s no significant gender difference of indicator PCBs, but theconcentration of indicator PCBs in city samples is significantly higher than the ruralsamples. The correlation between each congener of indicator PCBs and total sevenindicator PCBs and Σ84PCBs are very significant.The analysis of PCBs in the serum and the usage of PCBs, concentration in the airand top soil in china indicate that composition characteristics in the serum is similar to chinese PCBs products,which means the chinese PCBs products may be the main sourceof serum PCBs. Serum PCBs concentration and the national PCBs usage list iscompared, it’s found that PCBs concentration from east and central regions of china ishigher than west regions, it shows that the human serum PCBs residual is influenced bytheir usage. Serum and air and top soil total PCBs is compared, and it’s found that eitherserum or air or soil, the concentration of total PCBs for city is significantly higher thanthe rural samples. Domestic and foreign studies of PCBs in human blood indicate thatthe highest PCBs concentration in human blood is in the region which is polluted byPCBs. The concentration of PCBs in this region is significantly higher than the otherregion, even as high as two orders of magnitude. The PCBs concentration in the generalpopulation is the lest, but still can be detected.The level of PCBs in adult is significantlyhigher than children, indicate that PCBs in the body is not easy removed from the bodybut gradually increase as the age increase. This research shows the serum PCBsconcentration at a lower level.The correlation between serum PCBS and longitude, latitude, population density,sex etc are analysis, indicate that the PCBS composition and distribution pattern aresignificantly correlate to longitude, population density, city countryside, but not to thelatitude and sex. Partial correlation analysis shows that the control variables whichaffect the correlations larger are longitude, urban and rural population density, while thegender and latitude to relevance almost no influence. The serum PCBs congener profileis significantly correlate to the congener profile of Chinese PCBs product and Chineseair.The analysis of bio-concentration of different congener in serum shows that thehigher Chlorine of PCBs which have larger lgBCF, the higher the ratio of the PCBscongener percentage to Chinese PCBs product and Chinese air congener percentage. Itmeans that the PCBs congener have different biological enrichment ability. The morechlorine atoms replaced,the stronger biological enrichment ability.