Samples of roadside dust were collected from 30 sites in Hong Kong.The total concentrations of 10 metals in the samples were analyzed,and the correlation coefficients among the metal contents and the annual average da...Samples of roadside dust were collected from 30 sites in Hong Kong.The total concentrations of 10 metals in the samples were analyzed,and the correlation coefficients among the metal contents and the annual average daily traffic(AADT)in 1986 were determined.Pb was found to have a significant correlation(P<0.01)with AADT.No correlation was found between Al, Ba,Cd,Cr,Cu,Fe,Mn,Ni,and Zn with respect to AADT.A general decrease in the level of Pb in roadside dust in the past few years has been observed since the reduction in the level of lead in petrol.1989 Academic Press,Inc.展开更多
In this study, we searched multiple databases for all relevant original articles (1996-2013). To investigate blood lead levels (BLL) and possible risk factors for lead exposure among children in China A total of 388 a...In this study, we searched multiple databases for all relevant original articles (1996-2013). To investigate blood lead levels (BLL) and possible risk factors for lead exposure among children in China A total of 388 articles met our inclusion criteria. The overall geometric mean (GM) BLL was 71 μg/L, and the prevalence of elevated BLL (EBLL, defined as BLL ≥100 μg/L) was 18.48% among children. The prevalence of EBLL remained significantly higher among boys. In children less than 6 years of age, there were significantly increasing trends in both BLL and prevalence of EBLL in an age-dependent manner. The ban on leaded gasoline significantly reduced the BLL as well as EBLL prevalence; however, children whose parents had lower educational levels or were exposed to lead in the workplace had a higher EBLL prevalence. Despite its decline over time, the average BLL among children in China remains higher than the average level most recently reported in the United States. Childhood lead poisoning remains a public health problem in China.展开更多
This study was designed to determine the cord blood lead (BPb) levels of babies born in one urban area of Shanghai, and to preliminarily identify the demographic, social environment and prenatal factors which have an ...This study was designed to determine the cord blood lead (BPb) levels of babies born in one urban area of Shanghai, and to preliminarily identify the demographic, social environment and prenatal factors which have an effect on the cord BPb concentrations. From August to November 1993, umbilical cord blood samples were obtained from 605 live newborns in the Yangpu Maternal and Child Hospital. 257 samples were excluded from measurement because of clotting. In 348 cord samples, the geometric mean of cord BPb levels was 9. 2μg/dl, with a 95 % confidence interval of the mean 8. 86-9. 54 (μg/dl). 142 babies (40. 8 % ) had cord BPb levels of 10μg/dl or greater. As a result of this high percentage of newborns with BPb levels equal to or greater than 10 μg/dl, we estimate that each year in the Shanghal City about 60,000 newborns are at risk for developing neuropsychological deficiencies caused by maternal lead exposure during pregnancy. To investigate the factors affecting cord blood levels, the subjects with levels greater than the 70th percentile (10. 7μg/dl) (n = 104) and less than the 3oth percentile (7. 4μg/dl) (n = 104) were selected to compare the demographic, environ ment and prenatal medical history. Increased BPb levels at birth were associated with maternal passive smoking, a family member being occupationally exposed to lead, proximity to major traffic way, household coal combustion, neighborhood coal combustion, low level of meternal occupations, and the increasing occurrence of having the high lead foodstuff pidan (preserved duck egg) during pregnancy. We conclude that prenatal lead exposure has become an impor tant health issue for young children in Shanghai展开更多
Concentrations of lead(Pb) were determined in leaf samples of \%Chromolaena adorata\% from a rural road and an urban road in Akwa Ibom State of Nigeria in relation to vehicular traffic density. Mixed results were obt...Concentrations of lead(Pb) were determined in leaf samples of \%Chromolaena adorata\% from a rural road and an urban road in Akwa Ibom State of Nigeria in relation to vehicular traffic density. Mixed results were obtained wich no trend to indict automobile exhaust fumes. Lead was not detected in rain water from these areas and leaf lead levels seemed to relate more to soil lead concentrations. There was no significant difference in mean leaf lead levels between rural and urban leaf samples and between washed and unwashed leaf samples. It was suggested that the lack of concordance between vehicular traffic density and lead levels in leaves along the highways indicates either a low level use of tetraethyl leaded petrol or, a relatively low vehicular traffic density with lead from exhaust fumes not reaching a threshold to affect levels in plants or be detected in the atmosphere. Implications of concentrations obtained in leaves to consumers when compared with international standards were discussed.展开更多
Lead,a heavy metal,which is nonessential but may be harmful to the human body,has been widely used to manufacture many products for use in the modern world.Lead-acid batteries have the advantages of low price,high saf...Lead,a heavy metal,which is nonessential but may be harmful to the human body,has been widely used to manufacture many products for use in the modern world.Lead-acid batteries have the advantages of low price,high safety,and advanced technology.展开更多
Objective To investigate the blood lead levels （BLLs） in the duration of pregnancy and 6-12 weeks after delivery, and analyze the influencing factors of BLLs in healthy pregnant women. Methods Pregnant women were r...Objective To investigate the blood lead levels （BLLs） in the duration of pregnancy and 6-12 weeks after delivery, and analyze the influencing factors of BLLs in healthy pregnant women. Methods Pregnant women were recruited from September 2009 to February 2010 at the prenatal clinic in Nanjing Maternity and Child Health Care Hospital. Altogether 174 healthy pregnant women without pregnant or obstetric complications or abnormal pregnancy outcomes were enrolled as the gravida group, and 120 healthy non-pregnant women as the control group. BLLs during pregnancy were determined by flame atomic absorption spectroscopy. Results BLLs in all the three pregnancy trimesters and postpartum were 59.8±24.3, 55.4±20.1, 55.9±19.7, and 67.6±17.4 μ/L, respectively, and the mean BLL in control group was 67.5±21.3 μg/L. BLLs during all the three trimesters were lower in the gravida group than in the control group （P=0.043, 0.021, and 0.028）. Furthermore, occupations, nutrients supplementation, and time of house/apartment painted were associated with BLLs in pregnant women. Lead-related occupations, cosmetics use, and living in a house painted less than 1 year before are risk factors of high BLLs among pregnant women, while calcium, iron, zinc, and milk supplements are protective factors. Conclusion Supplementing calcium, iron, zinc, and milk, or avoiding contact with risk factors may help people, especially pregnant women, to reduce lead exposure.展开更多
Economic responsibility audit is an important part of the socialist audit supervision system with Chinese characteristics.It is an important responsibility of audit institutions at all levels to carry out economic res...Economic responsibility audit is an important part of the socialist audit supervision system with Chinese characteristics.It is an important responsibility of audit institutions at all levels to carry out economic responsibility audit.This article conducts a comprehensive and profound analysis of the problems existing in the current grassroots economic responsibility audit work.In addition,countermeasures and suggestions are proposed in this article,which are of positive significance to promote the economic responsibility audit work of leading cadres.展开更多
Lead is an important toxic heavy metal among environment pollution. Some industrial parks were founded in 2005 including non-ferrous metal processing and smelting plants. In order to identify the consequence of lead p...Lead is an important toxic heavy metal among environment pollution. Some industrial parks were founded in 2005 including non-ferrous metal processing and smelting plants. In order to identify the consequence of lead pollution on children around the industry park, blood samples of neighboring children were collected and analyzed in laboratory. The results showed that the involved children have suffered serious harms from Pb pollution. Almost 75% of the children＇s blood lead levels （BLLs） exceeded the limit of normal blood lead. Worse still, 26.17% of them were at the level of Moderate lead poisoning. The group aged 0-7 showed more susceptibility to Pb than that aged 8-14. Only 19.05% of the children aged 0-7 were at the level of normal blood lead, compared with 45.45% in the group aged 8-14. There was no significant difference between the values of blood lead concentration for male and female or among different age groups. Some approaches, which include controlling the Pb pollution from the industry park and safeguarding the residents, esp. the children were suggested.展开更多
Pregnancy is a critical stimulator of bone mineral resorption. We used to find the MTHFR gene polymorphisms are related with blood lead levels among pregnant women. Pregnancy-stimulated bone turnover may be associated...Pregnancy is a critical stimulator of bone mineral resorption. We used to find the MTHFR gene polymorphisms are related with blood lead levels among pregnant women. Pregnancy-stimulated bone turnover may be associated with MTHFR gene polymorphisms too. In this article, we aimed to determine the relationship between MTHFR gene polymorphisms and bone turnover rates among the pregnant women. The participants including pregnant and non-pregnant women were selected and recruited during their routine prenatal or physical examination from July to October in 2012. A total of 1000 participants, including 250 pregnant women in the first, second, and third trimesters and 250 non-pregnant women, were enrolled in the study. Finally, after excluding 27 participants unable to provide blood samples, 973 eligible participants （i.e., 234, 249, and 248 pregnant women in the first, second, and third trimesters, respectively, and 242 non-pregnant women） were included in the research. The MTHFR gene 1298CC homozygote carriers were more susceptible to yield higher plasma homocysteine levels than the 1298AA/AC carriers, with standardized coefficients of 0.086 （P〈0.05） and 0.104 （P〈0.01） of all the participants and the pregnant women, respectively. The MTHFR gene 1793AA homozygote carriers more likely showed higher plasma osteocalcin levels （standardized β=0.091, P〈0.01） than the 1793GG/GA carriers among all the subjects. Plasma homocysteine levels were positively correlated with blood lead levels among the participants and the pregnant women with standardized coefficients of 0.320 （P〈0.01） and 0.179 （P〈0.01）, respectively. Plasma osteocalcin levels were positively associated with blood lead levels among pregnant and non-pregnant women with standardized coefficients of 0.084 （P〈0.05） and 0.125 （P〈0.01）, respectively. In conclusion, homocysteine and osteocalcin contents in plasma are associated with the MTHFR gene A1298C polymorphism and blood lead levels among pregnant women. The MTHFR gene A1298C polymorphism-related homocysteine is a possible risk factor for increased blood lead levels among Chinese women.展开更多
Although considerable research has been conducted regarding airborne lead exposures during lead paint removal, little data has been collected measuring the lead concentration on workers’ hands in the construction ind...Although considerable research has been conducted regarding airborne lead exposures during lead paint removal, little data has been collected measuring the lead concentration on workers’ hands in the construction industry. As a result, there are gaps in our understanding of the effectiveness of a standard work practice control (handwashing) in the prevention and control of elevated blood lead levels (BLLs) in the workplace. The primary objective of this study was to assess if a National Institute for Occupational Safety and Health (NIOSH) formulation intended to remove lead from skin (Hygenall<sup><span style="white-space:nowrap;">© </span></sup>Leadoff<sup>TM</sup> Foaming Soap) is more effective than a commonly used soap in the industrial painting industry (Zep Cherry Bomb Soap) in reducing the concentration of lead on workers’ hands after exposure. A secondary aim was to assess if using Leadoff<sup>TM</sup> Foaming Soap during handwashing reduces worker uptake of lead on bridge painting projects. We evaluated hand wipe, air sample and blood lead level data collected by two industrial bridge painting contractors. Airborne exposures ranged from 350 μg/m<sup>3</sup> to 19,700 μg/m<sup>3</sup>. The geometric mean lead concentration remaining on workers’ hands after using Zep Cherry Bomb Soap was 77 μg per hand wipe compared with 61 μg per hand wipe after use of Leadoff<sup>TM</sup> Foaming Soap for all work classifications. The geometric lead concentration on workers’ hands decreased by 16 μg/hand wipe for all work classifications combined after using Leadoff<sup>TM</sup> Foaming Soap—a decrease of 21%. The use of Hygenall Leadoff<sup>TM</sup> Foaming Soap reduced the maximum lead concentration on workers’ hands by 85%. The geometric mean BLL for all work classifications was 12.1 μg/dl before the use of Leadoff<sup>TM</sup>. After two months of airborne exposure and use of Leadoff<sup>TM</sup> Foaming Soap at breaks and at the end of the workday, the geometric mean BLL for all work classifications increased to 18.1 μg/dl. Worker BLLs increased despite the reduction in the concentration of lead measured on workers’ hands—most likely a result of ineffective inhalation exposure controls. We found that the Leadoff<sup>TM</sup> Foaming Soap was more effective in removing lead from workers’ hands than Zep Cherry Bomb.展开更多
Geophagia (the pica of pottery, clay, earth, or dirt) is practiced before and during pregnancy in several countries, including Mexico, Turkey, Australia, and some African countries, and has been linked with cultural f...Geophagia (the pica of pottery, clay, earth, or dirt) is practiced before and during pregnancy in several countries, including Mexico, Turkey, Australia, and some African countries, and has been linked with cultural fertility beliefs and the satisfaction of cravings. Unfortunately, consumption of contaminated pottery can represent a source of lead exposure. Concerns regarding ingested pottery are two-fold;first, that people consuming these pots might be exposed to high concentrations of lead, and, second, that ingestion of these pots by pregnant women could result in elevated in utero lead exposure for the fetus. Very few published articles exist on this topic. In an effort to investigate “pot eating”, this study aims to summarize published case studies on lead poisonings resulting from consumption of contaminated pottery. Additionally, several pottery items that are sold for the purpose of consumption were located and analyzed. This paper investigates the risk that “pot eating” poses by reviewing the literature, examining case studies, and analyzing the availability and lead concentration of edible pottery. Preliminary research indicates that although it is not common, “pot eating” can represent a high-risk lead exposure for pregnant women and their fetuses.展开更多
To evaluate the effectiveness of personal hygiene (handwashing) amongst workers at industrial sites to remove lead from their hands, a retrospective analysis of hand wipe samples was conducted using data collected by ...To evaluate the effectiveness of personal hygiene (handwashing) amongst workers at industrial sites to remove lead from their hands, a retrospective analysis of hand wipe samples was conducted using data collected by two contractors from two bridge painting projects for total lead using method ASTM E-1979-17/EPA SW846 7000B. Exposures resulted from the removal of lead-based paint from the structure and trace elements of lead found in the abrasive blast media. In total, six work tasks were evaluated and sixty unique hand wipe samples were evaluated. Thirty samples were collected during the worker’s lunch break, after they had reportedly washed their hands with a further 30 collected at the end of the workday following the same protocol. To be included in this evaluation, the contractors were required to follow NIOSH Method 9105 (Lead in Dust Wipes-Dermal Surfaces) with subsequent analysis of samples for total lead by an American Industrial Hygiene Association (AIHA) accredited laboratory. All 60 samples contained detectable lead. The lead exposures ranged from 19.5 μg to 3420 μg. The geometric mean for the samples collected was 337 μg. These results indicate that current personal hygiene practices at the evaluated sites are not effective at removing lead from worker’s hands during and after the workday. They also suggest that the residual lead measured on the workers’ hands, at the end of the shift, is likely contributing to the elevated blood lead levels in this population.展开更多
With only a few deep-level defect states having a high formation energy and dominance of shallow carrier non-trapping defects,the defect-tolerant electronic and optical properties of lead halide perovskites have made ...With only a few deep-level defect states having a high formation energy and dominance of shallow carrier non-trapping defects,the defect-tolerant electronic and optical properties of lead halide perovskites have made them appealing materials for high-efficiency,low-cost,solar cells and light-emitting devices.As such,recent observations of apparently deep-level and highly luminescent states in low-dimensional perovskites have attracted enormous attention as well as intensive debates.The observed green emission in 2D CsPb2Br5 and 0 D Cs4PbBr6 poses an enigma over whether it is originated from intrinsic point defects or simply from highly luminescent CsPbBr3 nanocrystals embedded in the otherwise transparent wide band gap semiconductors.The nature of deep-level edge emission in 2D Ruddlesden–Popper perovskites is also not well understood.In this mini review,the experimental evidences that support the opposing interpretations are analyzed,and challenges and root causes forthe controversy are discussed.Shortcomings in the current density functional theory approaches to modeling of properties and intrinsic point defects in lead halide perovskites are also noted.Selected experimental approaches are suggested to better correlate property with structure of a material and help resolve the controversies.Understanding and identification of the origin of luminescent centers will help design and engineer perovskites for wide device applications.展开更多
Background Non-ST-segment elevation acute coronary syndrome （NSTE-ACS） is an acute heart disease caused by incomplete occlusion of related coronary arteries with unstable atherosclerotic plaques. Lead aVR ST- segmen...Background Non-ST-segment elevation acute coronary syndrome （NSTE-ACS） is an acute heart disease caused by incomplete occlusion of related coronary arteries with unstable atherosclerotic plaques. Lead aVR ST- segment elevation and cTnI positive are closely correlated to the prognosis of NSTE-ACS patients. However, there are few studies applying the two predictors to early risk stratification in NSTE-ACS patients. Method Two hundred and five cases of NSTE-ACS patients followed up for 6 months after discharge were reviewed. All patients were divided into four groups： Group A-cTnI negative combined with aVR-non-ST-segment elevation group （100 cases） ; Group B-cTnI negative combined with aVR-ST-segment elevation group （31 cases） ; Group C-cTnI positive combined with aVR-non-ST-segment elevation group （43 cases） ; Group D-cTnI positive combined with aVR-ST-segment elevation group （31 cases）. There was no significant difference in gender, age, old myocardial infarction, previous PCI history, hypertension, and diabetes between aVR-ST elevation group and no aVR-ST elevation group. The morbidity of left main or three-vessel coronary artery disease as well as adverse cardiovascular events in the four groups were observed and analyzed. Results （i） The morbidity of left main or three-vessel coronary artery disease was highest in Group D （87.1%） , and was markedly higher in Group B （41.9%） than that in Group A （7%） or Group C （9.3%） ; （ii） The incidence of adverse cardiovascular events was highest in Group D （77.4%）, and was much higher in B （35.5%） as compared with that tin Group A （1%） or group C （7%）. Conclusion Electrocardiographic lead aVR ST-segment elevation combined with cTnI positive has an important clinical value in predicting the prognosis of the patients with NSTE-ACS.展开更多
An attempt is made in this paper to describe the following laws governing the distribution of lead-zinc deposits in China: spatial distribution laws, temporal distribution laws, deep level control laws, and deposits a...An attempt is made in this paper to describe the following laws governing the distribution of lead-zinc deposits in China: spatial distribution laws, temporal distribution laws, deep level control laws, and deposits association and zoning laws.展开更多
文摘Samples of roadside dust were collected from 30 sites in Hong Kong.The total concentrations of 10 metals in the samples were analyzed,and the correlation coefficients among the metal contents and the annual average daily traffic(AADT)in 1986 were determined.Pb was found to have a significant correlation(P<0.01)with AADT.No correlation was found between Al, Ba,Cd,Cr,Cu,Fe,Mn,Ni,and Zn with respect to AADT.A general decrease in the level of Pb in roadside dust in the past few years has been observed since the reduction in the level of lead in petrol.1989 Academic Press,Inc.
基金supported by The National Natural Science Foundation of China(No.81172628)the Fundamental Research Funds for the Central Universities(No.2014305020201)
文摘In this study, we searched multiple databases for all relevant original articles (1996-2013). To investigate blood lead levels (BLL) and possible risk factors for lead exposure among children in China A total of 388 articles met our inclusion criteria. The overall geometric mean (GM) BLL was 71 μg/L, and the prevalence of elevated BLL (EBLL, defined as BLL ≥100 μg/L) was 18.48% among children. The prevalence of EBLL remained significantly higher among boys. In children less than 6 years of age, there were significantly increasing trends in both BLL and prevalence of EBLL in an age-dependent manner. The ban on leaded gasoline significantly reduced the BLL as well as EBLL prevalence; however, children whose parents had lower educational levels or were exposed to lead in the workplace had a higher EBLL prevalence. Despite its decline over time, the average BLL among children in China remains higher than the average level most recently reported in the United States. Childhood lead poisoning remains a public health problem in China.
文摘This study was designed to determine the cord blood lead (BPb) levels of babies born in one urban area of Shanghai, and to preliminarily identify the demographic, social environment and prenatal factors which have an effect on the cord BPb concentrations. From August to November 1993, umbilical cord blood samples were obtained from 605 live newborns in the Yangpu Maternal and Child Hospital. 257 samples were excluded from measurement because of clotting. In 348 cord samples, the geometric mean of cord BPb levels was 9. 2μg/dl, with a 95 % confidence interval of the mean 8. 86-9. 54 (μg/dl). 142 babies (40. 8 % ) had cord BPb levels of 10μg/dl or greater. As a result of this high percentage of newborns with BPb levels equal to or greater than 10 μg/dl, we estimate that each year in the Shanghal City about 60,000 newborns are at risk for developing neuropsychological deficiencies caused by maternal lead exposure during pregnancy. To investigate the factors affecting cord blood levels, the subjects with levels greater than the 70th percentile (10. 7μg/dl) (n = 104) and less than the 3oth percentile (7. 4μg/dl) (n = 104) were selected to compare the demographic, environ ment and prenatal medical history. Increased BPb levels at birth were associated with maternal passive smoking, a family member being occupationally exposed to lead, proximity to major traffic way, household coal combustion, neighborhood coal combustion, low level of meternal occupations, and the increasing occurrence of having the high lead foodstuff pidan (preserved duck egg) during pregnancy. We conclude that prenatal lead exposure has become an impor tant health issue for young children in Shanghai
文摘Concentrations of lead(Pb) were determined in leaf samples of \%Chromolaena adorata\% from a rural road and an urban road in Akwa Ibom State of Nigeria in relation to vehicular traffic density. Mixed results were obtained wich no trend to indict automobile exhaust fumes. Lead was not detected in rain water from these areas and leaf lead levels seemed to relate more to soil lead concentrations. There was no significant difference in mean leaf lead levels between rural and urban leaf samples and between washed and unwashed leaf samples. It was suggested that the lack of concordance between vehicular traffic density and lead levels in leaves along the highways indicates either a low level use of tetraethyl leaded petrol or, a relatively low vehicular traffic density with lead from exhaust fumes not reaching a threshold to affect levels in plants or be detected in the atmosphere. Implications of concentrations obtained in leaves to consumers when compared with international standards were discussed.
基金financially supported by the Jiangsu Province Special Project of Clinical Science and Technology[Grant No.BL2014082]the Jiangsu Provincial Medical Innovation Team[CXTDA2017029]the Jiangsu Provincial Medical Youth Talent[QNRC2016548]
文摘Lead,a heavy metal,which is nonessential but may be harmful to the human body,has been widely used to manufacture many products for use in the modern world.Lead-acid batteries have the advantages of low price,high safety,and advanced technology.
基金supported by Nanjing Maternity and Child Health Care Hospital
文摘Objective To investigate the blood lead levels （BLLs） in the duration of pregnancy and 6-12 weeks after delivery, and analyze the influencing factors of BLLs in healthy pregnant women. Methods Pregnant women were recruited from September 2009 to February 2010 at the prenatal clinic in Nanjing Maternity and Child Health Care Hospital. Altogether 174 healthy pregnant women without pregnant or obstetric complications or abnormal pregnancy outcomes were enrolled as the gravida group, and 120 healthy non-pregnant women as the control group. BLLs during pregnancy were determined by flame atomic absorption spectroscopy. Results BLLs in all the three pregnancy trimesters and postpartum were 59.8±24.3, 55.4±20.1, 55.9±19.7, and 67.6±17.4 μ/L, respectively, and the mean BLL in control group was 67.5±21.3 μg/L. BLLs during all the three trimesters were lower in the gravida group than in the control group （P=0.043, 0.021, and 0.028）. Furthermore, occupations, nutrients supplementation, and time of house/apartment painted were associated with BLLs in pregnant women. Lead-related occupations, cosmetics use, and living in a house painted less than 1 year before are risk factors of high BLLs among pregnant women, while calcium, iron, zinc, and milk supplements are protective factors. Conclusion Supplementing calcium, iron, zinc, and milk, or avoiding contact with risk factors may help people, especially pregnant women, to reduce lead exposure.
文摘Economic responsibility audit is an important part of the socialist audit supervision system with Chinese characteristics.It is an important responsibility of audit institutions at all levels to carry out economic responsibility audit.This article conducts a comprehensive and profound analysis of the problems existing in the current grassroots economic responsibility audit work.In addition,countermeasures and suggestions are proposed in this article,which are of positive significance to promote the economic responsibility audit work of leading cadres.
文摘Lead is an important toxic heavy metal among environment pollution. Some industrial parks were founded in 2005 including non-ferrous metal processing and smelting plants. In order to identify the consequence of lead pollution on children around the industry park, blood samples of neighboring children were collected and analyzed in laboratory. The results showed that the involved children have suffered serious harms from Pb pollution. Almost 75% of the children＇s blood lead levels （BLLs） exceeded the limit of normal blood lead. Worse still, 26.17% of them were at the level of Moderate lead poisoning. The group aged 0-7 showed more susceptibility to Pb than that aged 8-14. Only 19.05% of the children aged 0-7 were at the level of normal blood lead, compared with 45.45% in the group aged 8-14. There was no significant difference between the values of blood lead concentration for male and female or among different age groups. Some approaches, which include controlling the Pb pollution from the industry park and safeguarding the residents, esp. the children were suggested.
基金This project was supported by grants-from the National Natural Science Foundation of China （No. 81573235）, Health and Family Commission of Hubei Province （No. 2015CFB376）, and Health and Family Commission of Wuhan Municipality （No. WG15D20）.
文摘Pregnancy is a critical stimulator of bone mineral resorption. We used to find the MTHFR gene polymorphisms are related with blood lead levels among pregnant women. Pregnancy-stimulated bone turnover may be associated with MTHFR gene polymorphisms too. In this article, we aimed to determine the relationship between MTHFR gene polymorphisms and bone turnover rates among the pregnant women. The participants including pregnant and non-pregnant women were selected and recruited during their routine prenatal or physical examination from July to October in 2012. A total of 1000 participants, including 250 pregnant women in the first, second, and third trimesters and 250 non-pregnant women, were enrolled in the study. Finally, after excluding 27 participants unable to provide blood samples, 973 eligible participants （i.e., 234, 249, and 248 pregnant women in the first, second, and third trimesters, respectively, and 242 non-pregnant women） were included in the research. The MTHFR gene 1298CC homozygote carriers were more susceptible to yield higher plasma homocysteine levels than the 1298AA/AC carriers, with standardized coefficients of 0.086 （P〈0.05） and 0.104 （P〈0.01） of all the participants and the pregnant women, respectively. The MTHFR gene 1793AA homozygote carriers more likely showed higher plasma osteocalcin levels （standardized β=0.091, P〈0.01） than the 1793GG/GA carriers among all the subjects. Plasma homocysteine levels were positively correlated with blood lead levels among the participants and the pregnant women with standardized coefficients of 0.320 （P〈0.01） and 0.179 （P〈0.01）, respectively. Plasma osteocalcin levels were positively associated with blood lead levels among pregnant and non-pregnant women with standardized coefficients of 0.084 （P〈0.05） and 0.125 （P〈0.01）, respectively. In conclusion, homocysteine and osteocalcin contents in plasma are associated with the MTHFR gene A1298C polymorphism and blood lead levels among pregnant women. The MTHFR gene A1298C polymorphism-related homocysteine is a possible risk factor for increased blood lead levels among Chinese women.
文摘Although considerable research has been conducted regarding airborne lead exposures during lead paint removal, little data has been collected measuring the lead concentration on workers’ hands in the construction industry. As a result, there are gaps in our understanding of the effectiveness of a standard work practice control (handwashing) in the prevention and control of elevated blood lead levels (BLLs) in the workplace. The primary objective of this study was to assess if a National Institute for Occupational Safety and Health (NIOSH) formulation intended to remove lead from skin (Hygenall<sup><span style="white-space:nowrap;">© </span></sup>Leadoff<sup>TM</sup> Foaming Soap) is more effective than a commonly used soap in the industrial painting industry (Zep Cherry Bomb Soap) in reducing the concentration of lead on workers’ hands after exposure. A secondary aim was to assess if using Leadoff<sup>TM</sup> Foaming Soap during handwashing reduces worker uptake of lead on bridge painting projects. We evaluated hand wipe, air sample and blood lead level data collected by two industrial bridge painting contractors. Airborne exposures ranged from 350 μg/m<sup>3</sup> to 19,700 μg/m<sup>3</sup>. The geometric mean lead concentration remaining on workers’ hands after using Zep Cherry Bomb Soap was 77 μg per hand wipe compared with 61 μg per hand wipe after use of Leadoff<sup>TM</sup> Foaming Soap for all work classifications. The geometric lead concentration on workers’ hands decreased by 16 μg/hand wipe for all work classifications combined after using Leadoff<sup>TM</sup> Foaming Soap—a decrease of 21%. The use of Hygenall Leadoff<sup>TM</sup> Foaming Soap reduced the maximum lead concentration on workers’ hands by 85%. The geometric mean BLL for all work classifications was 12.1 μg/dl before the use of Leadoff<sup>TM</sup>. After two months of airborne exposure and use of Leadoff<sup>TM</sup> Foaming Soap at breaks and at the end of the workday, the geometric mean BLL for all work classifications increased to 18.1 μg/dl. Worker BLLs increased despite the reduction in the concentration of lead measured on workers’ hands—most likely a result of ineffective inhalation exposure controls. We found that the Leadoff<sup>TM</sup> Foaming Soap was more effective in removing lead from workers’ hands than Zep Cherry Bomb.
文摘Geophagia (the pica of pottery, clay, earth, or dirt) is practiced before and during pregnancy in several countries, including Mexico, Turkey, Australia, and some African countries, and has been linked with cultural fertility beliefs and the satisfaction of cravings. Unfortunately, consumption of contaminated pottery can represent a source of lead exposure. Concerns regarding ingested pottery are two-fold;first, that people consuming these pots might be exposed to high concentrations of lead, and, second, that ingestion of these pots by pregnant women could result in elevated in utero lead exposure for the fetus. Very few published articles exist on this topic. In an effort to investigate “pot eating”, this study aims to summarize published case studies on lead poisonings resulting from consumption of contaminated pottery. Additionally, several pottery items that are sold for the purpose of consumption were located and analyzed. This paper investigates the risk that “pot eating” poses by reviewing the literature, examining case studies, and analyzing the availability and lead concentration of edible pottery. Preliminary research indicates that although it is not common, “pot eating” can represent a high-risk lead exposure for pregnant women and their fetuses.
文摘To evaluate the effectiveness of personal hygiene (handwashing) amongst workers at industrial sites to remove lead from their hands, a retrospective analysis of hand wipe samples was conducted using data collected by two contractors from two bridge painting projects for total lead using method ASTM E-1979-17/EPA SW846 7000B. Exposures resulted from the removal of lead-based paint from the structure and trace elements of lead found in the abrasive blast media. In total, six work tasks were evaluated and sixty unique hand wipe samples were evaluated. Thirty samples were collected during the worker’s lunch break, after they had reportedly washed their hands with a further 30 collected at the end of the workday following the same protocol. To be included in this evaluation, the contractors were required to follow NIOSH Method 9105 (Lead in Dust Wipes-Dermal Surfaces) with subsequent analysis of samples for total lead by an American Industrial Hygiene Association (AIHA) accredited laboratory. All 60 samples contained detectable lead. The lead exposures ranged from 19.5 μg to 3420 μg. The geometric mean for the samples collected was 337 μg. These results indicate that current personal hygiene practices at the evaluated sites are not effective at removing lead from worker’s hands during and after the workday. They also suggest that the residual lead measured on the workers’ hands, at the end of the shift, is likely contributing to the elevated blood lead levels in this population.
基金support from the Robert A.Welch Foundation(E-1728)National Science Foundation(EEC-1530753)supported by the State of Texas through the Texas Center for superconductivity at the University of Houston
文摘With only a few deep-level defect states having a high formation energy and dominance of shallow carrier non-trapping defects,the defect-tolerant electronic and optical properties of lead halide perovskites have made them appealing materials for high-efficiency,low-cost,solar cells and light-emitting devices.As such,recent observations of apparently deep-level and highly luminescent states in low-dimensional perovskites have attracted enormous attention as well as intensive debates.The observed green emission in 2D CsPb2Br5 and 0 D Cs4PbBr6 poses an enigma over whether it is originated from intrinsic point defects or simply from highly luminescent CsPbBr3 nanocrystals embedded in the otherwise transparent wide band gap semiconductors.The nature of deep-level edge emission in 2D Ruddlesden–Popper perovskites is also not well understood.In this mini review,the experimental evidences that support the opposing interpretations are analyzed,and challenges and root causes forthe controversy are discussed.Shortcomings in the current density functional theory approaches to modeling of properties and intrinsic point defects in lead halide perovskites are also noted.Selected experimental approaches are suggested to better correlate property with structure of a material and help resolve the controversies.Understanding and identification of the origin of luminescent centers will help design and engineer perovskites for wide device applications.
文摘Background Non-ST-segment elevation acute coronary syndrome （NSTE-ACS） is an acute heart disease caused by incomplete occlusion of related coronary arteries with unstable atherosclerotic plaques. Lead aVR ST- segment elevation and cTnI positive are closely correlated to the prognosis of NSTE-ACS patients. However, there are few studies applying the two predictors to early risk stratification in NSTE-ACS patients. Method Two hundred and five cases of NSTE-ACS patients followed up for 6 months after discharge were reviewed. All patients were divided into four groups： Group A-cTnI negative combined with aVR-non-ST-segment elevation group （100 cases） ; Group B-cTnI negative combined with aVR-ST-segment elevation group （31 cases） ; Group C-cTnI positive combined with aVR-non-ST-segment elevation group （43 cases） ; Group D-cTnI positive combined with aVR-ST-segment elevation group （31 cases）. There was no significant difference in gender, age, old myocardial infarction, previous PCI history, hypertension, and diabetes between aVR-ST elevation group and no aVR-ST elevation group. The morbidity of left main or three-vessel coronary artery disease as well as adverse cardiovascular events in the four groups were observed and analyzed. Results （i） The morbidity of left main or three-vessel coronary artery disease was highest in Group D （87.1%） , and was markedly higher in Group B （41.9%） than that in Group A （7%） or Group C （9.3%） ; （ii） The incidence of adverse cardiovascular events was highest in Group D （77.4%）, and was much higher in B （35.5%） as compared with that tin Group A （1%） or group C （7%）. Conclusion Electrocardiographic lead aVR ST-segment elevation combined with cTnI positive has an important clinical value in predicting the prognosis of the patients with NSTE-ACS.
文摘An attempt is made in this paper to describe the following laws governing the distribution of lead-zinc deposits in China: spatial distribution laws, temporal distribution laws, deep level control laws, and deposits association and zoning laws.
