采用微波消解-电感耦合等离子体发射光谱法测定苹果干制品中铅、镉、砷的含量。经试验优化而确定的微波消化条件为加入2 m L浓硝酸,电热板温度86℃,预消化30 min,放冷至室温后加入1 m L双氧水,盖好盖子,装好罐,微波消化,定容后用ICP-AE...采用微波消解-电感耦合等离子体发射光谱法测定苹果干制品中铅、镉、砷的含量。经试验优化而确定的微波消化条件为加入2 m L浓硝酸,电热板温度86℃,预消化30 min,放冷至室温后加入1 m L双氧水,盖好盖子,装好罐,微波消化,定容后用ICP-AES检测。经分析,该方法回收率好,为93%～104%。从测定的结果可看出,苹果干制品中重金属含量为Pb〈0.2 mg/kg,Cd〈0.1 mg/kg,As〈0.2 mg/kg,为苹果干制品产品标准的制定提供依据。展开更多
Objective To evaluate levels of lead(Pb) and cadmium(Cd) in the breast milk in the second postpartum month,to investigate the relationship between Pb/Cd levels in breast milk and some sociodemographic parameters,and t...Objective To evaluate levels of lead(Pb) and cadmium(Cd) in the breast milk in the second postpartum month,to investigate the relationship between Pb/Cd levels in breast milk and some sociodemographic parameters,and to explore whether these levels affect the infants' physical status or the mothers' psychological status(postpartum depression).Methods A cross-sectional study was conducted between November 2009 and December 2010.Altogether 170 healthy mothers were enrolled from Nanjing Maternity and Child Health Care Hospital.The inclusion criteria were:voluntary to participate in this study,healthy,with no chronic disease,breastfeeding in the second postpartum month,living in a suburban but not non-industrial area of Nanjing,and not occupationally exposed to toxic metals.All the mothers completed a questionnaire and were evaluated based on the Edinburgh Postpartum Depression Scale(EPDS) to identify the risk of postpartum depression.Pb and Cd levels in breast milk were determined by inductively coupled plasma mass spectroscopy.The infants of these mothers were examined for their z scores of weight for age,length for age,head circumference for age,and body mass index for age.Results The median breast milk levels of Pb and Cd were 40.6 μg/L and 0.67 μg/L,respectively.In 164(96.5%) of the 170 samples,Pb levels were higher than the limit reported by the World Health Organization(> 5 μg/L).Breast milk Cd level was > 1 μg/L in 54(31.8%) mothers.The mothers with a history of anemia had a higher breast milk Pb level than those without a history of anemia(41.1 μg/L vs.37.9 μg/L,P = 0.050).The median breast milk Cd level in those who were active and passive smokers during pregnancy was significantly higher than that in non-smokers(0.88 μg/L vs.0.00 μg/L,P = 0.025).The breast milk Cd level in the mothers not taking iron and vitamin supplements for 2 months postpartum was higher than in those taking the supplements(iron supplement:0.74 μg/L vs.0.00 μg/L,P = 0.025;vitamin supplement:0.78 μg/L vs.0.00 μg/L,P = 0.005).Breast milk Cd level at the second postpartum month was negatively correlated with the z scores of head circumference(r = 0.248,P = 0.042) and weight for age at birth(r = 0.241,P = 0.024) in girls.No correlation was found between the breast milk Pb/Cd levels and the EPDS scores.Conclusion Considering the high levels of Pb and Cd in breast milk in this study,breast milk monitoring programs are necessary.展开更多
Up to now, the evaporation and condensation, as well as the biological absorption and inorganic absorptions, have been proved to be major factors in Cd isotope fractionation. And Cd isotopes have been widely applied i...Up to now, the evaporation and condensation, as well as the biological absorption and inorganic absorptions, have been proved to be major factors in Cd isotope fractionation. And Cd isotopes have been widely applied in studies on the universal evolution and marine environment and so on. However, only a few researches have been conducted in applying Cd isotopes to trace the source of metallogenic material and the evolution of the ore-forming fluid in a complex mineralization environment, especially in a hydrothermal ore-formation system. We measured the Cd isotopic compositions of sphalerite, galena, and ores from five lead-zinc deposits in SW China, and found that the ~14/11~Cd values varied from -1.53%o to 0.34%0, with a total range of 1.87%o, which is greater than most of measured geological samples. Meanwhile, through contrasting the Cd content with Cd isotopic compositions of different deposits, it may be concluded that different genetic lead-zinc deposits have different Cd content and isotopic compositions, which could be a tool for the studies on the origin of ore deposits. Also, the biominera]iza- tion and crystal fractionation may also result in Cd isotope fractionation. In a word, although the research of Cd isotopes is presently at the preliminary stage （especially in hydrothermal ore-formation system）, this study demonstrated that Cd isotopes can give a clue in tracing the evolution of ore-forming fluid and metallogenic environment.展开更多
文摘采用微波消解-电感耦合等离子体发射光谱法测定苹果干制品中铅、镉、砷的含量。经试验优化而确定的微波消化条件为加入2 m L浓硝酸,电热板温度86℃,预消化30 min,放冷至室温后加入1 m L双氧水,盖好盖子,装好罐,微波消化,定容后用ICP-AES检测。经分析,该方法回收率好,为93%～104%。从测定的结果可看出,苹果干制品中重金属含量为Pb〈0.2 mg/kg,Cd〈0.1 mg/kg,As〈0.2 mg/kg,为苹果干制品产品标准的制定提供依据。
基金supported by Nanjing Maternity and Child Health Care Hospital
文摘Objective To evaluate levels of lead(Pb) and cadmium(Cd) in the breast milk in the second postpartum month,to investigate the relationship between Pb/Cd levels in breast milk and some sociodemographic parameters,and to explore whether these levels affect the infants' physical status or the mothers' psychological status(postpartum depression).Methods A cross-sectional study was conducted between November 2009 and December 2010.Altogether 170 healthy mothers were enrolled from Nanjing Maternity and Child Health Care Hospital.The inclusion criteria were:voluntary to participate in this study,healthy,with no chronic disease,breastfeeding in the second postpartum month,living in a suburban but not non-industrial area of Nanjing,and not occupationally exposed to toxic metals.All the mothers completed a questionnaire and were evaluated based on the Edinburgh Postpartum Depression Scale(EPDS) to identify the risk of postpartum depression.Pb and Cd levels in breast milk were determined by inductively coupled plasma mass spectroscopy.The infants of these mothers were examined for their z scores of weight for age,length for age,head circumference for age,and body mass index for age.Results The median breast milk levels of Pb and Cd were 40.6 μg/L and 0.67 μg/L,respectively.In 164(96.5%) of the 170 samples,Pb levels were higher than the limit reported by the World Health Organization(> 5 μg/L).Breast milk Cd level was > 1 μg/L in 54(31.8%) mothers.The mothers with a history of anemia had a higher breast milk Pb level than those without a history of anemia(41.1 μg/L vs.37.9 μg/L,P = 0.050).The median breast milk Cd level in those who were active and passive smokers during pregnancy was significantly higher than that in non-smokers(0.88 μg/L vs.0.00 μg/L,P = 0.025).The breast milk Cd level in the mothers not taking iron and vitamin supplements for 2 months postpartum was higher than in those taking the supplements(iron supplement:0.74 μg/L vs.0.00 μg/L,P = 0.025;vitamin supplement:0.78 μg/L vs.0.00 μg/L,P = 0.005).Breast milk Cd level at the second postpartum month was negatively correlated with the z scores of head circumference(r = 0.248,P = 0.042) and weight for age at birth(r = 0.241,P = 0.024) in girls.No correlation was found between the breast milk Pb/Cd levels and the EPDS scores.Conclusion Considering the high levels of Pb and Cd in breast milk in this study,breast milk monitoring programs are necessary.
基金supported by National Basic Research Program of China(Grant No.2009CB421005)Chinese Academy of Sciences for Key Topics in Innovation Engineering(Grant No.KZCX2-YW-Q04-01)
文摘Up to now, the evaporation and condensation, as well as the biological absorption and inorganic absorptions, have been proved to be major factors in Cd isotope fractionation. And Cd isotopes have been widely applied in studies on the universal evolution and marine environment and so on. However, only a few researches have been conducted in applying Cd isotopes to trace the source of metallogenic material and the evolution of the ore-forming fluid in a complex mineralization environment, especially in a hydrothermal ore-formation system. We measured the Cd isotopic compositions of sphalerite, galena, and ores from five lead-zinc deposits in SW China, and found that the ~14/11~Cd values varied from -1.53%o to 0.34%0, with a total range of 1.87%o, which is greater than most of measured geological samples. Meanwhile, through contrasting the Cd content with Cd isotopic compositions of different deposits, it may be concluded that different genetic lead-zinc deposits have different Cd content and isotopic compositions, which could be a tool for the studies on the origin of ore deposits. Also, the biominera]iza- tion and crystal fractionation may also result in Cd isotope fractionation. In a word, although the research of Cd isotopes is presently at the preliminary stage （especially in hydrothermal ore-formation system）, this study demonstrated that Cd isotopes can give a clue in tracing the evolution of ore-forming fluid and metallogenic environment.
