The possible health risks of heavy metals contamination to local population through food chain were evaluated in Beijing and Tianjin city cluster, China, where have a long history of sewage irrigation. The transfer fa...The possible health risks of heavy metals contamination to local population through food chain were evaluated in Beijing and Tianjin city cluster, China, where have a long history of sewage irrigation. The transfer factors （TF） for heavy metals from soil to vegetables for six elements including Cu, Zn, Pb, Cr, As and Cd were calculated and the pollution load indexes （PLI） were also assessed. Results indicate that only Cd exceeded the maximum acceptable limit in these sites. So far, the heavy metal concentrations in soils and vegetables were all below the permissible limits set by the Ministry of Environmental Protection of China and World Health Organization. The transfer factors of six heavy metals showed the trend as Cd 〉 Zn 〉 Cu 〉 Pb 〉 As 〉 Cr, which were dependent on the vegetable species. The estimated dietary intakes of Cu, Zn, Pb, Cr, As and Cd were far below the tolerable limits and the target hazard quotient （THQ） values were less than 1, which suggested that the health risks of heavy metals exposure through consuming vegetables were generally assumed to be safe.展开更多
Phytoremediation offers a cost-effective, non-intrusive, and safe alternative to conventional cleanup techniques. In this study, we used ornamental hydrophytes plants as constructed wetlands to treat urban or rural do...Phytoremediation offers a cost-effective, non-intrusive, and safe alternative to conventional cleanup techniques. In this study, we used ornamental hydrophytes plants as constructed wetlands to treat urban or rural domestic wastewater. Most ornamental hydrophytes adapted to the wastewater well, and were fairly efficient in scavenging BOD5 （biological oxygen demand 5 d）, COD （chemical oxygen demand）, TN （total nitrogen）, TP （total phosphorus） and heavy metals （Cr, Pb, Cd） in the wastewater. However, the efficiency varied a lot for various species to different contaminants, Iris pseudacorus L. and Acorus gramineus Soland were good choices for treatment of composite-polluted urban wastewater. Some variation in the change of membrane peroxidation and endogenous protective system in responses to wastewater was found among six hydrophytes, which have a correlation with the efficiency of wastewater treatment. It may demonstrate that the developed antioxidative systems of L pseudacorus and A. gramineus contributed much to their superiority. On the other hand, interaction of different components in the wastewater might have certain effects on phytoremediation.展开更多
基金supported by the Major Projects of Knowledge Innovation Program of Chinese Academy of Sciences(No. KZCX2-YW-Q02-05)the Beijing Science and Technology Program (No. D101105046410004)
文摘The possible health risks of heavy metals contamination to local population through food chain were evaluated in Beijing and Tianjin city cluster, China, where have a long history of sewage irrigation. The transfer factors （TF） for heavy metals from soil to vegetables for six elements including Cu, Zn, Pb, Cr, As and Cd were calculated and the pollution load indexes （PLI） were also assessed. Results indicate that only Cd exceeded the maximum acceptable limit in these sites. So far, the heavy metal concentrations in soils and vegetables were all below the permissible limits set by the Ministry of Environmental Protection of China and World Health Organization. The transfer factors of six heavy metals showed the trend as Cd 〉 Zn 〉 Cu 〉 Pb 〉 As 〉 Cr, which were dependent on the vegetable species. The estimated dietary intakes of Cu, Zn, Pb, Cr, As and Cd were far below the tolerable limits and the target hazard quotient （THQ） values were less than 1, which suggested that the health risks of heavy metals exposure through consuming vegetables were generally assumed to be safe.
基金Project supported by the Key Science and Technology Program of Zhejiang Province(No.2005C24011)the Open Fund of Ministry of Education Key Lab of Environment Remediafion and Ecological Health(No. 2005204).
文摘Phytoremediation offers a cost-effective, non-intrusive, and safe alternative to conventional cleanup techniques. In this study, we used ornamental hydrophytes plants as constructed wetlands to treat urban or rural domestic wastewater. Most ornamental hydrophytes adapted to the wastewater well, and were fairly efficient in scavenging BOD5 （biological oxygen demand 5 d）, COD （chemical oxygen demand）, TN （total nitrogen）, TP （total phosphorus） and heavy metals （Cr, Pb, Cd） in the wastewater. However, the efficiency varied a lot for various species to different contaminants, Iris pseudacorus L. and Acorus gramineus Soland were good choices for treatment of composite-polluted urban wastewater. Some variation in the change of membrane peroxidation and endogenous protective system in responses to wastewater was found among six hydrophytes, which have a correlation with the efficiency of wastewater treatment. It may demonstrate that the developed antioxidative systems of L pseudacorus and A. gramineus contributed much to their superiority. On the other hand, interaction of different components in the wastewater might have certain effects on phytoremediation.
