Combined pollution of heavy metals and PAHs and its risk assessment in industrial sites of Chenzhou city
郴州工业场地重金属和PAHs复合污染特征及风险评价

This paper investigated the pollution of heavy metals and polycyclic aromatic hydrocarbons(PAHs) in three typical industrial contaminated sites such as coke power plant,coal mining and smelting industry in Chenzhou city,southern China.The results showed that the pollution of Pb,Zn,Cu,As and PAHs in the soil of smelting industrial sites was serious,with more than 50% samples exceeding the limits and the highest concentration exceeding the standards by 100 times.In coal mining sites,it was shown that 87.5% of the samples were above the arsenic limits and 75% of the samples were above the PAHs limits.In coke power plants,81.2% of the samples exceeded the limits and the maximum content of PAHs exceeded the standards by 34 times.It was estimated that the sources for PAHs were different in the three industrial sites.The PAHs of power plants and coal mine sites mainly originated from coal combustion and petroleum,respectively,while the PAHs of smelting plants were mainly from mixed source of coal combustion and petroleum.It was suggested that arsenic and PAHs were widely observed in industrial sites,and some heavy metals such as Pb were significantly correlated with PAHs.The pollution risks of PAHs and heavy metals were estimated in the order of smelting industrial sites >coke power plants > coal mining sites.It was assessed that the pollution risk of PAHs in power plants was the highest,and that the pollution risk of heavy metals in smelting industrial sites was the highest.