广东贵屿土壤Cd、Hg潜在威胁评价

通过表层土壤、深层土壤、水稻样品及水样的采取与分析,结果表明,水俣病的元凶Hg在广东省贵屿镇土壤中具有极高的富集系数,易在酸性条件下向有效形态转化的弱有机结合态Hg占全Hg的17.74%;痛痛病的元凶Cd在部分土壤中的含量已超过环境承受的极限,且最易与生命体发生作用的水溶态Cd和离子交换态Cd占全Cd的比例高达16.2%。Hg、Cd的块金系数均大于70%,具明显的表层富集特征,与家电拆解作坊表层土壤重金属元素同源性较好,说明Cd、Hg的分布、富集受人类活动影响强烈,其对生态环境和居民健康存在极强的潜在威胁,在特定条件下有可能引发各类地方病。

Potential Threat of Cd, Hg in Soil of Guiyu, Guangdong Province

Guiyu is located in the junction of Chaoyang,Puning and Jieyang.It is a famous "first town of electronic-waste".Electronic-waste in the local has caused serious environmental pollution and damaged the health of residents.The research showed the Hg which is the main cause of Minamata disease has a high soil enrichment factor in the town.The weak organic-bound Cd which could easily transform to Hg under acidic conditions accounts for 17.74% of the total content.Cd is the main cause of Itai-itai disease.The content of Cd in some soil has exceeded the environmental limit.The content of water-soluble Cd and ion-exchange Cd which can most easily influence living body accounts for 16.2% of the total content.The nugget coefficient of Hg and Cd were more than 70%,which has a significant surface enrichment characteristics and has good homology with heavy metals in surface soil of dismantling workshops.This showed that the distribution and enrichment characteristics of Cd and Hg are affected by human activities significantly,and existence of a potential threat to environment and health of residents under certain conditions may lead to endemic diseases.