Assessment of soil chromium contamination in tannery sludge storage areas

• 作 者: Yongqiang Yuan Shen Yu Lili Wei Yunfeng He
• 机 构: Key laboratory of Urban Environment and health,Institute of Urban Environment,Chinese Academy of Sci
• 出 处: The 17th International Conference on Heavy Metals in the Env
• 发表日期: 2014年4期
• 关键词: tannery sludge storage areas soil chromium contamination assessment

　　Chromium(Cr)has emerged as a priority pollutant due to its harmful to human health.Anthropogenic activities do increase the release of Cr to environments.Chrome-tanning agents were widely used in the traditional process in tannery industry,which lead to a large amount of Cr entering into the soil.Although these chemicals have been banned in the new process standard since 2008,historical chromium pollution in areas cannot be ignored,especially where these lands have been changed to residential uses.Six tannery sludge storage sites in Zhejiang Province,China,were investigated in this study.Storage time of the sites A,B,C,D,E and F were approximately 20-30,10-15,5-10,3-5,1-3,and 0-1 years,respectively.Out of the six sites,the E and F sites follow the new process and the A and B sites were out of service.Total soil Cr contents are 781,22257,30600,34500,1618 and 2059 mg?kg-1 for the six sites,respectively,indicating soil Cr content for the traditional process was about 20 times higher than that for the new process.In addition,all sites overran the soil environmental quality standard for residential use(400 mg Cr?kg-1,GB15618-2008).Total soil Cr content showed a first-order linear attenuation trend(y=42875-1389x,R2=0.9964,or y=40848-1980x,R2=0.9985,n=18,for different attenuation rate,according to the upper and lower limits of storage time at each site)with loading time,assuming that soil texture and other properties did not influence Cr attenuation.According to the attenuation rate,soil Cr attenuation would be taken at least 12-25 years,such as the B site,declining to the environmental quality standard of residential land use.This study suggests that it is necessary to remedy soil Cr contamination in these sites before the residential development.