Lead Hazards Research Articles

Biological Fractionation of Lead Isotopes in Sprague-Dawley Rats Lead Poisoned via the Respiratory Tract

ObjectivesIt was considered that lead isotope ratios did not change during physical, chemical, or biological processes. Thus, lead isotope ratios have been used as fingerprints to identify possible lead sources. However, recent evidence has shown that the lead isotope ratios among different biological samples in human are not always identical from its lead origins in vitro. An animal experiment was conducted to explore the biological fractionation of lead isotopes in biological systems.Methods24 male Sprague-Dawley (SD) rats were divided into groups that received acute lead exposure (0, 0.02, 0.2, or 2 mg/kg body weight of lead acetate) via the respiratory route every day for 5 days. Biological samples (i.e., blood, urine, and feces) were collected for comparison with the lead acetate (test substance) and the low-lead animal feed (diet) administered to the rats. The lead isotope ratios were determined by inductively coupled plasma mass spectrometry (ICP-MS).ResultsThere are significant differences (p<0.05) in lead isotope ratios between blood, urine, and feces. Moreover, a nonlinear relationship between the blood lead concentration and the blood lead isotope ratios was observed. There is also a threshold effect to the fractionation function. Only the blood isotope ratio of 204Pb/206Pb matches the test substance well. As for feces, when 204Pb/206Pb ratio is considered, there is no significant difference between feces-test substance pairs in medium and high dose group.ConclusionsThe biological fractionation of lead isotopes in SD rats was observed. Moreover, there might be a threshold for the biological fractionation of lead isotopes which is depending on whole blood lead level. It is considered to be more reliable that we compared the isotope ratios of potential lead hazards with both blood and feces lead fingerprints especially for 204Pb/206Pb ratio under high-dose exposure.

Heavy Weight Protein Affected by Lead Acetate in Bactrocera dorsalis

The studies were carried out on toxic effects of lead acetate, which could contaminate the environment, such as food, water, air and soil, therefore insects could be influenced easily by the lead., Bactrocera dorsalis was studied at 48 hours post treatment, under the effects of lead acetate, in different concentrations. It was observed that, under the effects of lead abnormalities, and deformity were developed in the larvae of flies. Thus these flies could present a useful module for the quick transmission of the environmental hazards of lead, which exerts a specific physiological and morphological effect on their bodies.

CDC Updates Guidelines for Children’s Lead Exposure

In response to the growing body of scientific evidence about effects of exposure to low levels of lead,1 the U.S. Centers for Disease Control and Prevention (CDC) has announced it is changing its guidelines for children’s exposure to the toxic metal, reducing by half the blood lead level at which intervention is recommended.2 According to CDC spokesman Jay Dempsey, the agency estimates the change will increase the number of affected children from fewer than 100,000 to 372,979. Recommended intervention involves identifying and removing sources of lead exposure and follow-up blood lead monitoring. Since 1991 the CDC’s “level of concern” for lead in children’s blood had been set at 10 µg/dL. At the recommendation of its Advisory Committee on Childhood Lead Poisoning Prevention, the agency is dispensing with the use of a static number. Instead, its new reference value of 5 µg/dL is based on the 97.5th percentile of blood lead levels in U.S. children aged 1–5 years, as measured by the agency’s National Health and Nutrition Examination Survey (NHANES). The reference value will be updated every four years based on the two most recent iterations of the NHANES.2 The CDC has moved away from the “level of concern” terminology because it “gives a false sense of security to people” whose children’s blood lead fell below the cutoff, says Christopher Portier, director of the agency’s National Center for Environmental Health. The agency and its advisory committee can find no evidence that there is a safe level of lead exposure for children, he says. Lead-based paint remains the most important source of lead poisoning for U.S. children.1 Despite the great reductions in exposure that followed the removal of lead from gasoline, an estimated 37.1 million U.S. homes still contain lead paint.6 Ingestion ... A host of studies now link exposure to lower levels of lead with behavior problems, attention deficit/hyperactivity disorder, and adverse cardiovascular, immunological, and endocrine effects, says Bruce Lanphear of Simon Fraser University. Lanphear led a 2005 study in which seven different longitudinal cohorts from multiple countries reported very similar decreases in intelligence in association with blood lead levels below 10 µg/dL.3 In June 2012 the National Toxicology Program concluded that adverse health effects occur at levels below even 5 µg/dL.4 Homes can be a major source of lead exposure, and the CDC is focused on primary prevention, says Mary Jean Brown, chief of the agency’s Lead Poisoning Prevention Branch. “We have to develop an agenda that controls or eliminates lead hazards before children are poisoned,” she says. The CDC is working with the U.S. Department of Housing and Urban Development and the U.S. Environmental Protection Agency to identify communities where high proportions of children have elevated lead levels and to take actions to remediate the sources of exposure, she says. “For most children, the majority of their exposure is from household dust that is a consequence of the decay of old lead-based paint,” says Michael Weitzman, a professor of environmental medicine and pediatrics at New York University’s Langone Medical Center. Old windows are a major source of exposure; another is renovating older homes without taking proper precautions, according to the nonprofit National Center for Healthy Housing (NCHH). However, less is known about how to clean up these sources of lead. Lanphear points to the need for effective, evidence-based methods for reducing lead in house dust, soil, water, and consumer products. He is working on a study that he says demonstrates the efficacy of lead hazard controls to reduce children’s blood lead levels. Despite dramatic cuts to the CDC’s Healthy Homes/Lead Poisoning Prevention Program in fiscal year 2012,5 the May 2012 announcement of the new reference value constitutes a promise of action, Portier says. He says the agency will develop educational materials to explain to health departments, pediatricians, nongovernmental organizations, and other groups what the change means and how to act on it. However, 80% of the program budget supported state and local lead-poisoning prevention programs that will no longer be funded, says Dempsey. Portier says he is beginning to see many of these programs wind down. No matter how the new guidelines are ultimately implemented, NCHH executive director Rebecca Morley hopes more families will start to understand that even very low lead exposures can cause harm. She says the decision will prompt follow-up educational activities to help ensure that “parents are going to begin to get the information that they deserve.”

Environmental Lead: Rabito et al. Respond

We thank Mielke for his interest in our study of residential lead hazards in New Orleans (Rabito et al. 2012). In our study we found that most homes had either dust or soil lead above federal standards and concluded that children are at risk for lead exposure. Regarding the specific issue of whether soil lead has increased or decreased, we agree that a direct comparison between census-level soil lead survey data and direct measure-ments of residential samples has limitations. To reiterate the limitations outlined in our article (Rabito et al. 2012), differences in the number of soil samples, the sampling methodology, and the sample location limited our ability to directly measure any change in soil lead levels. Although it is of interest to know whether soil lead has increased or decreased as a result of Hurricane Katrina, our focus was to measure current residential lead hazards, because lead contamination in and around homes is the primary pathway of exposure for children (Lanphear and Roghmann 1997). Our finding that 61% of homes had lead levels above federal standards provides evidence that New Orleans children are at high risk of exposure. That the samples were collected from homes typically considered to be low risk (given the socio-demographic characteristics of the sample) is cause for added concern. In his letter, Mielke refers to trends in blood lead levels. The issue of whether blood lead levels are increasing or decreasing in New Orleans children—which was not within the scope of our study (Rabito et al. 2012)—is not easily addressed using surveillance data. Screening practices and rates drive the reported prevalence in any given year. Zahran et al. (2010) compared aggregate blood lead levels derived from the Louisiana Childhood Blood Lead Surveillance System (CBLSS) pre-Hurricane Katrina to levels post-Hurricane Katrina and found that median blood lead had decreased. However, profound changes in the socio-demographic makeup of the New Orleans population make the comparison vulnerable to significant bias (Bloomberg 2011). The surveillance data provided by Mielke supports our notion that the post-Hurricane Katrina population screened under the CBLSS is not stable from year to year. As stated by Mielke, 6.4% of children had elevated blood lead levels in 2008, but the estimate decreased to 3.3% in 2010. This decrease might not be valid because the majority of children in the 2008 cohort were from the inner city (with the highest prevalence of old housing) whereas the 2010 cohort included a higher proportion from outer areas of the city (considered low risk based on housing age). The assumption by Zahran et al. (2010) that soil lead serves as a proxy for length of lead exposure is likely not valid given the amount of housing destabilization and subsequent mobility of the population in the years following the storm. Finally, low screening rates, coupled with a reporting level of > 10 µg/dL (widely accepted as above the level of concern) does not allow for the valid estimation of the preva-lence of elevated blood lead levels in New Orleans children. Regardless of the inconclusive nature of blood lead data, given that 61% of sampled homes have significant lead hazards, we maintain that New Orleans children who live in old housing are at risk for lead exposure independent of race or income. We support the recent statement by the Centers for Disease Control and Prevention Advisory Committee on Childhood Lead Poisoning Prevention that “the goal of primary prevention is to ensure that all homes become lead-safe and do not contribute to childhood lead exposure” (Centers for Disease Control and Prevention 2012). The City of New Orleans has made strides in its fight to reduce lead hazards in public places; however, they should not relax in their efforts to protect the environ-ment from further contamination.

Environmental Lead after Hurricane Katrina

I support the warning from Rabito et al. (2012) about the hazards of power sanding and their call for enforcing the New Orleans, Louisiana, Code of Ordinances (2001) and U.S. Environmental Protection Agency (EPA) Renovation, Repair, and Painting Rule (U.S. EPA 2008) for cleanup of residual lead dust at residential properties. Power sanding has been a scourge to the safety and well-being of children and pets in New Orleans for many years (Jacobs et al. 2003; Mielke et al. 2001). Unfortunately, Rabito et al. (2012) made a fundamental error by comparing medians from soil data (Mielke et al. 2005), which I shared with them, with principally foundation soil data. These medians included four sample locations: foundation, open space (i.e., mid-yard), residential-street side, and busy-street side. Comparing pre-Katrina median soil lead from our survey with foundation soil samples post-Katrina does not provide insight into foundation soil lead changes stemming from renovation. Furthermore, evidence from Louisiana blood lead surveillance shows decreasing—not increasing—exposure after Hurricane Katrina. The 2008 Orleans Parish results show that 38.5% of the children were tested, and 6.4% of these presented with lead concentrations ≥ 10 µg/dL (Louisiana Childhood Blood Lead Surveillance System 2009). In 2010, 40.0% of the children in Orleans Parish were tested, including a higher proportion of children from outer areas of New Orleans, and 3.3% presented with ≥ 10 µg/dL (Louisiana Childhood Blood Lead Surveillance System 2010). The continuing pattern of lead poisoning is uneven, with larger preva-lence in the interior of the city and lower prevalence in outer areas of the city (Zahran et al. 2011, their Figure 1). From the perspective of lead changes in soil and blood, both measurements decreased after Katrina (Zahran et al. 2010). Although large numbers of children are still at risk from lead poisoning, the blood lead trends reported for New Orleans do not support the future implications suggested by Rabito et al. (2012). Regarding the future, it is important to note that New Orleans is under-taking improvements to playgrounds so children will have lead-safe play areas in every neighborhood (Schleifstein 2011). A project is also under way to improve the quality of play areas at New Orleans child care centers (Mielke et al. 2011a). In addition, projects to eliminate lead-based paint and soil lead hazards at public housing properties are ongoing (Reckdahl 2011). The implications are that in the future, New Orleans will be safer with respect to lead. Private residential properties often have higher risk for lead poisoning than do public properties (Mielke et al. 2011b), and Rabito et al. have appropriately called attention to the need to address lead contamination of private residential properties.

Standards for the contents of heavy metals and metalloids in soils

In line with the present-day ecological and toxicological data obtained by Dutch ecologists, heavy metals/metalloids form the following succession according to their hazard degree in soils: Se > Tl > Sb > Cd > V > Hg > Ni > Cu > Cr > As > Ba. This sequence substantially differs from the succession of heavy elements presented in the general toxicological GOST (State Norms and Standards) 17.4.1.02-8, which considers As, Cd, Hg, Se, Pb, and Zn to be strongly hazardous elements, whereas Co, Ni, Mo, Sb, and Cr to be moderately hazardous. As compared to the general toxicological approach, the hazard of lead, zinc, and cobalt is lower in soils, and that of vanadium, antimony, and barium is higher. The new sequence also differs from that of the metal hazard in soils according to the Russian standard on the maximal permissible concentration of mobile metal forms (MPCmob): Cu > Ni > Co > Cr > Zn. Neither an MPCmob nor an APCmob has been adopted for strongly hazardous thallium, selenium, and vanadium in Russia. The content of heavy metals in contaminated soils is very unevenly studied: 11 of them, i.e., Cu, Zn, Pb, Ni, Cd, Cr, As, Mn, Co, Hg, and Se, are better known, while the rest, much worse, although there are dangerous elements (Ba, V, Tl) among them.

Window replacement and residential lead paint hazard control 12 years later

Window replacement is a key method of reducing childhood lead exposure, but the long-term effectiveness has not been previously evaluated. Windows have the highest levels of interior lead paint and dust compared to other building components. Our objective was to conduct a follow-up study of residential window replacement and lead hazard control 12 years after homes were enrolled in an evaluation of the HUD Lead Hazard Control Grant Program, sampling settled lead dust in housing in four cities (n=189 homes). Previous work evaluated lead hazard controls up to 6 years after intervention using dust lead measurements and two years after intervention using both dust and blood lead data. But the earlier work could not examine the effect of window replacement over the longer time period examined here: 12 years. The individual homes were assigned to one of three categories, based on how many windows had been replaced: all replacement, some replacement, or non-replacement. Windows that were not replaced were repaired. We controlled for covariates such as site, housing condition, presence of lead paint, and season using longitudinal regression modeling. Adjusted floor and sill dust lead geometric mean dust lead loadings declined at least 85% from pre-intervention to 12 years after the intervention for homes with all replacement windows, some windows replaced and no windows replaced. Twelve years after intervention, homes with all replacement windows had 41% lower interior floor dust lead, compared to non-replacement homes (1.4 versus 2.4μg/ft2, p<0.001), and window sill dust lead was 51% lower (25 versus 52μg/ft2, p=0.006) while controlling for covariates. Homes with some windows replaced had interior floor and window sill dust lead loadings that were 28% (1.7 versus 2.4μg/ft2, p=0.19) and 37% (33 versus 52μg/ft2, p=0.07) lower, respectively, compared to non-replacement homes. The net economic benefit of window replacement compared to window repair (non-replacement) is $1700–$2000 per housing unit. Homes in which all windows were replaced had significantly lower lead dust. New windows are also likely to reduce energy use and improve home value. Lead-safe window replacement is an important element of lead hazard control, weatherization, renovation and housing investment strategies and should be implemented broadly to protect children.

Remediating Soil Lead with Fish Bones

Remediating Soil Lead with Fish Bones

63: Childhood lead poisoning prevention through prenatal housing inspection and remediation in St. Louis, Missouri

Children in St. Louis have lead poisoning rates 4 times the national average and are at risk for neurodevelopment disabilities including decreased intelligence and increased behavioral dysfunction. Current strategies to prevent lead poisoning rely on identification of poisoned children, then treating homes to prevent further damage. Primary prevention prevents lead poisoning prior to irreparable brain damage. The Heavy Metal Project assessed the feasibility and effectiveness of screening and remediating lead hazards prenatally in a high risk population.

Environmental Lead after Hurricane Katrina: Implications for Future Populations

Background: As a result of Hurricane Katrina, > 100,000 homes were destroyed or damaged and a significant amount of sediment was deposited throughout the city of New Orleans, Louisiana. Researchers have identified the potential for increased lead hazards from environmental lead contamination of soils.Objectives: We assessed the distribution of residential soil and dust lead 2 years poststorm and compared soil lead before and after the storm.Methods: We conducted a cross-sectional study in New Orleans in which households were selected by stratified random sampling. A standard residential questionnaire was administered, and lead testing was performed for both the interior and exterior of homes. Logistic regression was used to identify significant predictors of interior and exterior lead levels in excess of allowable levels.Results: One hundred nine households were enrolled; 61% had at least one lead measurement above federal standards. Of homes with bare soil, 47% had elevated lead and 27% had levels exceeding 1,200 ppm. Housing age was associated with soil lead, and housing age and soil lead were associated with interior lead. Race, income, and ownership status were not significantly associated with either interior or exterior lead levels. The median soil lead level of 560 ppm was significantly higher than the median level of samples collected before Hurricane Katrina.Conclusions: The high prevalence (61%) of lead above recommended levels in soil and dust samples in and around residences raises concern about potential health risks to the New Orleans population, most notably children. Steps should be taken to mitigate the risk of exposure to lead-contaminated soil and dust. Further research is needed to quantify the possible contribution of reconstruction activities to environmental lead levels.

Rochester’s Lead Law: Evaluation of a Local Environmental Health Policy Innovation

Background: Significant progress has been made in reducing the incidence of childhood lead poisoning in the United States in the past three decades. However, the prevalence of elevated blood lead in children (≥ 10 μg/dL) remains high in some communities, particularly those with high proportions of pre-1978 housing in poor condition. Increasingly, municipalities are using local policy tools to reduce lead poisoning in high-risk areas, but little is known about the effectiveness of such policies.Objectives: In this article, we evaluated the effectiveness of a comprehensive rental housing–based lead law adopted in Rochester, New York, in 2005.Methods: This policy evaluation integrates analyses of city inspections data, a survey of landlords, landlord focus groups, and health department data on children’s blood lead levels from the first 4 years of implementation of the 2005 law.Results: Implementation has proceeded consistent with projected numbers of inspections with nearly all target units inspected in the first 4 years. Higher than expected inspection passage rates suggest that landlords have reduced lead hazards in rental housing affected by the law. Implementation of the lead law does not appear to have had a significant impact on the housing market.Conclusions: Although many uncertainties remain, our analysis suggests that the lead law has had a positive impact on children’s health. Strong enforcement, support for community-based lead programs, and ongoing intergovernmental coordination will be necessary to maintain lead-safe housing in Rochester. Lessons learned from the Rochester experience may inform future local lead poisoning prevention policies in other communities.

Childhood lead exposure in France: benefit estimation and partial cost-benefit analysis of lead hazard control

BackgroundLead exposure remains a public health concern due to its serious adverse effects, such as cognitive and behavioral impairment: children younger than six years of age being the most vulnerable population. In Europe, the lead-related economic impacts have not been examined in detail. We estimate the annual costs in France due to childhood exposure and, through a cost benefit analysis (CBA), aim to assess the expected social and economic benefits of exposure abatement.MethodsMonetary benefits were assessed in terms of avoided national costs. We used results from a 2008 survey on blood-lead (B-Pb) concentrations in French children aged one to six years old. Given the absence of a threshold concentration being established, we performed a sensitivity analysis assuming different hypothetical threshold values for toxicity above 15 μg/L, 24 μg/L and 100 μg/L. Adverse health outcomes of lead exposure were translated into social burden and economic costs based on literature data from literature. Direct health benefits, social benefits and intangible avoided costs were included. Costs of pollutant exposure control were partially estimated in regard to homes lead-based paint decontamination, investments aiming at reducing industrial lead emissions and removal of all lead drinking water pipes.ResultsThe following overall annual benefits for the three hypothetical thresholds values in 2008 are: €22.72 billion, €10.72 billion and €0.44 billion, respectively. Costs from abatement ranged from €0.9 billion to 2.95 billion/year. Finally, from a partial CBA of lead control in soils and dust the estimates of total net benefits were € 3.78 billion, € 1.88 billion and €0.25 billion respectively for the three hypothesized B-Pb effect values.ConclusionsPrevention of childhood lead exposure has a high social benefit, due to reduction of B-Pb concentrations to levels below 15 μg/L or 24 μg/L, respectively. Reducing only exposures above 100 μg/L B-Pb has little economic impact due to the small number of children who now exhibit such high exposure levels. Prudent public policies would help avoiding future medical interventions, limit the need for special education and increase future productivity, and hence lifetime income for children exposed to lead.

Characterization of lead in US workplaces using data from OSHA's integrated management information system

Lead hazards continue to be encountered in the workplace. OSHA's Integrated Management Information System (IMIS) is the largest available database containing sampling results in US workplaces. Personal airborne lead sampling results in IMIS were extracted for years 1979-2008. Descriptive analyses, geographical mapping, and regression modeling of results were performed. Seventy-nine percent of lead samples were in the manufacturing sector. Lead sample results were highest in the construction sector (median = 0.03 mg/m(3) ). NORA sector, year, OSHA region, number of employees at the worksite, federal/state OSHA plan, unionization, advance notification, and presence of an employee representative were statistically associated with having a lead sample result exceed the PEL. Lead concentrations within construction have been higher than any other industry. Lead hazards have been most prevalent in the north and northeastern US. IMIS data can be useful as a surveillance tool and for targeting prevention efforts toward hazardous industries.

Environmental hazard of cadmium, copper, lead and zinc in metal-contaminated soils remediated by sulfosuccinamate formulation

Accumulation of metals in soil at elevated concentrations causes risks to the environmental quality and human health for more than one hundred million people globally. The rate of metal release and the alteration of metal distribution in soil phases after soil washing with a sulfosuccinamate surfactant solution (Aerosol 22) were evaluated for four contaminated soils. Furthermore, a sequential extraction scheme was carried out using selective extractants (HAcO, NH(2)OH·HCl, H(2)O(2) + NH(4)AcO) to evaluate which metal species are extracted by A22 and the alteration in metal distribution upon surfactant-washing. Efficiency of A22 to remove metals varied among soils. The washing treatment released up to 50% of Cd, 40% of Cu, 20% of Pb and 12% of Zn, mainly from the soluble and reducible soil fractions, therefore, greatly reducing the fraction of metals readily available in soil. Metal speciation analysis for the solutions collected upon soil washing with Aerosol 22 further confirmed these results. Copper and lead in solution were mostly present as soluble complexes, while Cd and Zn were present as free ions. Besides, redistribution of metals in soil was observed upon washing. The ratios of Zn strongly retained in the soil matrix and Cd complexed with organic ligands increased. Lead was mobilized to more weakly retained forms, which indicates a high bioavailability of the remaining Pb in soil after washing. Comprehensive knowledge on chemical forms of metals present in soil allows a feasible assessment of the environmental impact of metals for a given scenario, as well as possible alteration of environmental conditions, and a valuable prediction for potential leaching and groundwater contamination.

Effects of HUD-supported lead hazard control interventions in housing on children's blood lead

The Evaluation of the US Department of Housing and Urban Development Lead-Based Paint Hazard Control Grant Program studied the effectiveness of the housing intervention performed in reducing the blood lead of children at four post-intervention times (6-months, 1-year, 2-years, and 3-years). A repeat measures analysis showed that blood lead levels declined up to three-years post-intervention. The results at each successive collection time were significantly lower than at the previous post-intervention time except for the difference between the levels at two and three years. At two-years post-intervention, geometric mean blood lead levels were approximately 37% lower than at pre-intervention. Children with pre-intervention blood lead levels as low as 10 μg/dL experienced substantial declines in blood lead levels. Previous studies have found substantial improvements only if a child's pre-intervention blood lead level was above 20 μg/dL. Individual interior lead hazard control treatments as grouped by Interior Strategy were not a significant predictor of post-intervention blood lead levels. However, children living in dwellings where exterior lead hazard control interventions were done had lower blood lead levels at one-year post-intervention than those living in dwellings without the exterior interventions (all other factors being equal), but those differences were only significant when the mean exterior paint lead loading at pre-intervention was about the 90th percentile (7.0 mg/cm 2). This observation suggests that exterior lead hazard control can be an important component of a lead hazard control plan. Children who were six to eleven months of age at pre-intervention had a significant increase in blood lead at one-year post-intervention, probably due to other exposures.

Evaluating and Regulating Lead in Synthetic Turf

BackgroundIn 2007, a synthetic turf recreational field in Newark, New Jersey, was closed because lead was found in synthetic turf fibers and in surface dust at concentrations exceeding hazard criteria. Consequently, public health professionals across the country began testing synthetic turf to determine whether it represented a lead hazard. Currently, no standardized methods exist to test for lead in synthetic turf or to assess lead hazards.ObjectivesOur objectives were to increase awareness of potential lead exposure from synthetic turf by presenting data showing elevated lead in fibers and turf-derived dust; identify risk assessment uncertainties; recommend that federal and/or state agencies determine appropriate methodologies for assessing lead in synthetic turf; and recommend an interim standardized approach for sampling, interpreting results, and taking health-protective actions.DiscussionData collected from recreational fields and child care centers indicate lead in synthetic turf fibers and dust at concentrations exceeding the Consumer Product Safety Improvement Act of 2008 statutory lead limit of 300 mg/kg for consumer products intended for use by children, and the U.S. Environmental Protection Agency’s lead-dust hazard standard of 40 μg/ft2 for floors.ConclusionsSynthetic turf can deteriorate to form dust containing lead at levels that may pose a risk to children. Given elevated lead levels in turf and dust on recreational fields and in child care settings, it is imperative that a consistent, nationwide approach for sampling, assessment, and action be developed. In the absence of a standardized approach, we offer an interim approach to assess potential lead hazards when evaluating synthetic turf.

Outline of lead hazards in battery factories reported in China between 1991 and 2008

目的 总结1991至2008年国内医药杂志上发表的文章中关于我国部分蓄电池企业职业性铅暴露、铅危害和铅中毒情况.方法 在 、 、 3个数据库检索1991至2009年所发表的有关蓄电池企业职业性铅暴露、铅危害和铅中毒的相关文献,检索的关键词为铅、铅暴露、铅危害、铅中毒、蓄电池.结果 2003至2008年,我国蓄电池企业的铅烟、铅尘浓度均较1991至2002年分别下降了37.14%、24.39%.2003至2008年,我国蓄电池企业铅烟、铅尘CTWA、超标倍数分别为7.3 mg/m3和6.2倍,CSTEL、超标倍数分别为18.7 mg/m3和32.0倍;1991至2002年,我国蓄电池企业铅烟、铅尘平均浓度分别为国家卫生标准的11.7和8.2倍,最大值分别为最高容许浓度的3884.7和5512.8倍.与1991至2002年相比,2003至2008年间各岗位的铅烟浓度均下降,最高为熔铅岗位(83.78%),依次为化成(71.79%)、浇铸(48.57%)、电焊岗位(21.95%);铅尘依次为化成(78.79%)、磨粉灌粉(77.29%)、装配(71.43%)、涂片工种(55.56%).结论 尽管我国蓄电池生产企业的铅烟、铅尘平均浓度较过去有明显下降,但仍然超过我国 中规定工作场所空气中铅烟、铅尘时间加权平均容许浓度(分别为0.03和0.05 mg/m3),铅污染及危害仍较严重,应继续加强监督和管理。

Housing Interventions and Control of Health-Related Chemical Agents

Subject matter experts systematically reviewed evidence on the effectiveness of housing interventions that affect health outcomes associated with exposure to chemical agents, such as pesticides, lead, volatile organic compounds, as well as the radon gas. Particulates were also examined, and the role of ventilation on exposures was assessed. The review included both published literature and peer-reviewed reports from the US Environmental Protection Agency. Four of the 14 interventions reviewed had sufficient evidence to demonstrate their effectiveness and are ready for implementation: radon air mitigation by using active soil depressurization systems, integrated pest management to reduce exposures to pesticides, smoke-free home policies making indoor areas smoke-free (ie, no smoking allowed anywhere at any time), and residential lead hazard control. Four interventions needed more field evaluation, 3 needed formative research, and 3 either had no sufficient evidence of effectiveness or had evidence the interventions were ineffective. This evidence review shows that housing improvements are likely to help reduce radon-induced lung cancer, cardiovascular mortality related to secondhand smoke, and neurological effects from exposure to pesticides and lead paint. Investing in housing interventions may yield important savings from reduced disease and injury from avoidable exposures to chemical agents.

Failing Our Children: Lead in U.S. School Drinking Water

Lead is the most prevalent toxicant in U. S. school drinking water. Yet for the vast majority of schools, federal regulation for testing taps and remediating contamination is voluntary. Using school case studies, this article discusses the regulatory vacuum that leaves children unprotected from potential exposure to very high lead doses through consumption of school water. Controlling lead hazards from water fountains, coolers, and other drinking water outlets in schools requires improved sampling protocols that can capture the inherent variability of lead release from plumbing and measure both the particulate and dissolved lead present in water. There is a need to reevaluate the potential public health implications of lead-contaminated drinking water in schools. Accounting for this misunderstood and largely overlooked exposure source is necessary in order to better understand and address childhood lead poisoning in the U. S.

Environmental contamination and health hazard of lead and cadmium around Chatian mercury mining deposit in western Hunan Province, China

A field survey concerning lead and cadmium pollution in environment mediums and hair samples around the Chatian mercury mining deposit in western Hunan Province, China, was conducted to preliminarily evaluate their health hazard to local inhabitants. The results show that mining wastes, especially tailing, contain high cadmium level with the maximum of 79.92 μg/g. High levels of lead and cadmium are accumulated in surface water and paddy soil, respectively, and both metals pollution occurs in brown rice. The average daily intake dose(ADD) of lead for local adults via three routes reaches up to 7.7 μg/(kg·d), exceeding the provision tolerable daily intake by JECFA of 3.5 μg/(kg·d), and drinking water exposure route contributes the highest daily intake. As an indicator for heavy metal exposure, the hair of local population contains Pb (5.06±3.02) μg/g. The average daily intake dose of cadmium for adults is 0.119 μg/(kg·d). More attention must be paid on health risk from lead pollution compared with cadmium.