Study On Mercury Pollution In Foods And Human Mercury Exposure In Typical Mercury Contaminated Areas,china

Objective: Mercury is considered as a global pollutant and had high toxicity which can adversely affect human health.Coal combustion,Pb/Zn smelter and large-scale gold production are most important anthropogenic mercury emission source in China,which maybe resulted in serious Hg pollution to local environment.However,human health risks of Hg exposure in these contaminated areas are unclear.Methods: In this study,we collected staple food(rice,fish etc.)and human hair samples at the three typical Hg polluted areas for total mercury(THg)and methylmercury(MeHg)analysis.Results: Around coal-fired power plant,the geometric averages of THg and MeHg concentration in human hair samples are 0.235 ?g/g(0.081~1.09 ?g/g,n=155)and 0.123 ?g/g(0.027~0.747 ?g/g,n=36),respectively,and THg concentrations in rice samples averaged at 3.63 ng/g(1.05~11.4 ng/g,n=126).Around Pb/Zn smelting area,the geometric average of THg and MeHg concentrations in human hair are 0.596 ?g/g(0.132~1.82 ?g/g,n=125)and 0.203 ?g/g(0.045~1.139 ?g/g,n=42),respectively,while 17% of hair THg concentrations exceed 1 ?g/g set by USEPA;THg concentration in rice samples averaged at 5.99 ng/g(3.02~30.7ng/g,n=70).At the surroundings of large-scale gold production,the geometric averages of THg and MeHg concentrations in human hair samples are 0.333?g/g(0.096~2.92 ?g/g,n=144)and 0.183 ?g/g(0.056~0.920 ?g/g,n=41),respectively,while 3.5% of hair THg concentrations exceed 1 ?g/g set by USEPA;THg concentrations in rice samples averaged at 4.46 ng/g(3.13~8.67 ng/g,n=65).Rice rather than fish consumption is the primary pathway of mercury exposure for local residents at the study region,which contributed 71.4%,77.2% and 70.8% of total probable daily intake(PDI)on average,respectively,which is similar to mercury mining area.Hair THg and MeHg concentrations in Pb/Zn smelting area were significantly elevated compared with other two areas,which indicated potential health risks for the local residents.Conclusion: Therefore,effective techniques should be conducted on Pb/Zn smelting to reduce Hg emission from this sector and to reduce human health risks of Hg exposure.