Inappropriate e-waste-processing operation is a serious issue in developing countries since the early 2000's.Field research was conducted to clarify its influences and diffuse toxic substances in the environment a...Inappropriate e-waste-processing operation is a serious issue in developing countries since the early 2000's.Field research was conducted to clarify its influences and diffuse toxic substances in the environment at e-waste-processing sites in a village in northern Vietnam from 2012 to 2014.We investigated surface soil samples collected from e-waste-processing sites,open burning sites,and rice paddy sites.Sediment samples and water samples were also collected from a river that runs through the village.The hazardous metal concentration in soil and river sediment samples indicated that 7 elements(Ca,Cu,Mo,Ni,Pb,Sn,and Zn)had high concentrations as a result of e-waste-processing.Most notably,Pb and Cu had high concentrations in soil samples(Pb:26e2200 mg/kg,Cu:22e3000 mg/kg).The results of a multivariate analysis indicated that these 7 elements were closely correlated with e-waste-processing.Concentrations of hazardous metals showed an upward trend where e-waste-processing occurred during the 3-year study period,although it was not significant statistically at present.Open burning activity had a great influence on Cu accumulation,and maximum Cu concentrations increased from 340 mg/kg in 2012e3000 mg/kg in 2014 in soil samples from open-burning sites.There were large differences in the dominant hazardous metal depending on the type of e-waste-processing workshop because hazardous metal composition was influenced by the types of e-waste and the processing procedures.It is necessary to avoid e-waste processing in open-air environment to control emissions of hazardous substances.Especially,open burning should be prohibited.展开更多
文摘Inappropriate e-waste-processing operation is a serious issue in developing countries since the early 2000's.Field research was conducted to clarify its influences and diffuse toxic substances in the environment at e-waste-processing sites in a village in northern Vietnam from 2012 to 2014.We investigated surface soil samples collected from e-waste-processing sites,open burning sites,and rice paddy sites.Sediment samples and water samples were also collected from a river that runs through the village.The hazardous metal concentration in soil and river sediment samples indicated that 7 elements(Ca,Cu,Mo,Ni,Pb,Sn,and Zn)had high concentrations as a result of e-waste-processing.Most notably,Pb and Cu had high concentrations in soil samples(Pb:26e2200 mg/kg,Cu:22e3000 mg/kg).The results of a multivariate analysis indicated that these 7 elements were closely correlated with e-waste-processing.Concentrations of hazardous metals showed an upward trend where e-waste-processing occurred during the 3-year study period,although it was not significant statistically at present.Open burning activity had a great influence on Cu accumulation,and maximum Cu concentrations increased from 340 mg/kg in 2012e3000 mg/kg in 2014 in soil samples from open-burning sites.There were large differences in the dominant hazardous metal depending on the type of e-waste-processing workshop because hazardous metal composition was influenced by the types of e-waste and the processing procedures.It is necessary to avoid e-waste processing in open-air environment to control emissions of hazardous substances.Especially,open burning should be prohibited.
