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Levels of Polychlorinated Biphenyls in Human Hair from Gongzhuling, Jilin

Author: ZhangLi
Tutor: ShiZhiHong；ChenYang；XuDianDou
School: Hebei University
Course: Analytical Chemistry
Keywords: polychlorinated biphenyl(PCB) hair GC-MS Gongzhuling,Jilin gender age
CLC: R114
Type: Master's thesis
Year: 2011
Downloads: 39
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Abstract

Persistent Organic Pollutants（POPs） with properties such as persistence,bioaccumulation, semi-volatility and high toxicity,can circulate through the world by atmosphere,sea current and other ways and cause serious world wide environment problem.They are bioaccumulated largely in lipid tissue,biomagnified along food chains and caused a range of adverse health effects to human.Polychlorinated Biphenyls（PCBs） are typical POPs with all properties that POPs has. The monitoring of PCBs in humans has become of paramount importance in human exposure and health risk assessment.To analyze the concentration of PCBs in human, lipid, blood, milk, liver and hair are convenient and effective methods for evaluating the level of environmental contamination with PCBs in environment on human health.Previous studies describing measurement methods for POPs in hair are limited. Northeast China is the heavy industrial base of our history,and PCBs have been used in that area for a long time,Leakage during the using process and improper handling after equipment retired cause serious pollution to the surrounding environment,however,there is no information of the pollution condition of PCBs in the environment that area.In order to evaluate the level of environmental contamination with PCBs in northeast China and carry out risk assessment on human health.The present study collected 116 hair samples from the general population of Gong zhuling, Jilin.,investigated volume and distribution of PCBs in human hair,and the relationships between age, gender and concentrations of various pollutants were also adressed as well.The results can provide some certain scientific bases for further research and risk assessment.Hair samples were incubated in HCl,extracted with hexane: dichloromethane （4:1）, purified by a Multi-column and analyzd for 30 polychlorinated biphenyl （PCB） congeners by gas chromatograph-mass spectrometer（GC-MS）.The distribution characteristics,sources as well as relationship with genders and age of PCBs in human hair were addressed.The results indicated that:（1）The method for analysis of PCBs in human hair were optimized. The average recoveries were 85.3%¹04.9%.Instrument detection limits and mothod detection limits were 0.008⁰.093 ng·g^-1and 0.18².12 ng·g^-1,respectively.This method meets the requirements of PCBs measurement in human hair which conform to international standards.（2） The detection frequency of PCBs is 100% for all samples with average concentration 79.04 ng·g^-1.The details are as follows:The average concentration of∑PCBs for 1^-12 years’old is （42.07±13.55） ng·g^-1 and detection range from 24.06 ng·g^-1 to 66.61 ng·g^-1;The average concentration of∑PCBs for 12^-18 years’old is （68.85±36.72） ng·g^-1 and detection range from 11.66 ng·g^-1 to 127.86 ng·g^-1;The average concentration of∑PCBs for 18-35 years’old is （67.93±32.29） ng·g^-1 and detection range from 13.03 ng·g^-1 to 274.11 ng·g^-1;The average concentration of∑PCBs for 35-50 years’old is （107.04±55.82） ng·g^-1 and detection range from 44.19 ng·g^-1 to 252.76 ng·g^-1;The average concentration of∑PCBs for 50-60 years’old is （101.78±34.35） ng·g^-1 and detection range from 38.94 ng·g^-1 to 176.74 ng·g^-1,respectively.This region was contaminated to some extent.（3） CB-28, CB-52, CB-87, CB-82, CB-87, CB180, CB114, CB126 were the major congeners which occupied 16%, 16%, 11%, 11%, 10%, 5%, 5% respectively. Penta-CBs were the dominant contributors（39%）, followed by tetra-CBs（24%） and tri-CBs（18%）.The different distributions of PCB congeners in hair from other human tissues and the air are believed to be the fact that PCBs in human hair not only came from endogenous dietary uptake of the contaminants, but also from exogenous atmospheric deposition. The results clearly indicated that these pollutants mainly came from industrial pollution.（4）Except 50-60 years’old,the mean level of most PCBs isomers were higher in female compared with male for every age group.Concentration and age correlated significantly for less metabolised PCBs,while not well for easy metabolised PCBs.

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