Heavy metal ions, one kind of harmful substance, may exist in the soil irrelevant to artificial development, and soil contamination, due to soil and rock containing these naturally derived heavy metals, has recently b...Heavy metal ions, one kind of harmful substance, may exist in the soil irrelevant to artificial development, and soil contamination, due to soil and rock containing these naturally derived heavy metals, has recently become apparent. Thus, in an amendment that came into effect in 2010 of Japan, the scope of countermeasures and regulations for contaminated soil was amended to “contaminated soil derived from artificial development” and “naturally derived contaminated soil”. When naturally derived contaminated soil is encountered during the carrying out of construction work, countermeasures against this type of soil contamination are necessary. In this research, new metal-insolubilizing materials are developed in order to improve the insolubilization treatment which is one method for treating contaminated soil. Specifically, tests are conducted to clarify the insolubilization effect on heavy metals, and the insolubilization mechanism is chemically and mineralogically discussed.展开更多
Time-dependent Zn and Cd accumulation and metallothionein like protein （MTLP） induction in the digestive glands of mussels, Perna virdis, were measured under different exposure conditions. The initial uptake rate at...Time-dependent Zn and Cd accumulation and metallothionein like protein （MTLP） induction in the digestive glands of mussels, Perna virdis, were measured under different exposure conditions. The initial uptake rate at start of chase （ρ0） and mean residence time （τ） were calculated to determine the physiological response of organisms and their potential detoxification mechanisms. It was found that in digestive glands, Zn had obviously higher ρ0 and shorter mean residence time than Cd, indicating that these two metals had different accumulation dynamics even though they were very close in the periodic element table. MTLP levels in digestive glands varied from 0.51 to 1.05 μg/g ww （wet weight）. The MTLP level increased continuously when mussels were exposed to low and middle levels of Zn and Cd media, and reached maximal levels at day 4, then decreased when they were exposed to high level Zn and Cd solutions. With regard to the fraction of Zn and Cd accumulated in the digestive glands, the ratios of soluble metal to total metal decreased continuously after exposure in low and middle levels of Zn and Cd media, and decreased continuously in the first 4 days and then to level off when mussels were exposed to media with high concentration of Zn and Cd. Results suggested that both MTLP induction and metal insolubilization were detoxification processes in digestive glands of mussels.展开更多
文摘Heavy metal ions, one kind of harmful substance, may exist in the soil irrelevant to artificial development, and soil contamination, due to soil and rock containing these naturally derived heavy metals, has recently become apparent. Thus, in an amendment that came into effect in 2010 of Japan, the scope of countermeasures and regulations for contaminated soil was amended to “contaminated soil derived from artificial development” and “naturally derived contaminated soil”. When naturally derived contaminated soil is encountered during the carrying out of construction work, countermeasures against this type of soil contamination are necessary. In this research, new metal-insolubilizing materials are developed in order to improve the insolubilization treatment which is one method for treating contaminated soil. Specifically, tests are conducted to clarify the insolubilization effect on heavy metals, and the insolubilization mechanism is chemically and mineralogically discussed.
基金supported by the National Natural Science Foundation of China (No. 40876039)the Science and Technology Program of China (No. 2008FY110100)the Foundation of Scientific and Technological Planning Project of Guangdong Province (No. 2006B36601005)
文摘Time-dependent Zn and Cd accumulation and metallothionein like protein （MTLP） induction in the digestive glands of mussels, Perna virdis, were measured under different exposure conditions. The initial uptake rate at start of chase （ρ0） and mean residence time （τ） were calculated to determine the physiological response of organisms and their potential detoxification mechanisms. It was found that in digestive glands, Zn had obviously higher ρ0 and shorter mean residence time than Cd, indicating that these two metals had different accumulation dynamics even though they were very close in the periodic element table. MTLP levels in digestive glands varied from 0.51 to 1.05 μg/g ww （wet weight）. The MTLP level increased continuously when mussels were exposed to low and middle levels of Zn and Cd media, and reached maximal levels at day 4, then decreased when they were exposed to high level Zn and Cd solutions. With regard to the fraction of Zn and Cd accumulated in the digestive glands, the ratios of soluble metal to total metal decreased continuously after exposure in low and middle levels of Zn and Cd media, and decreased continuously in the first 4 days and then to level off when mussels were exposed to media with high concentration of Zn and Cd. Results suggested that both MTLP induction and metal insolubilization were detoxification processes in digestive glands of mussels.
