The objectives of this study are to demonstrate for the first time the use of a field portable X-Ray Fluorescence Analyzer (XRF) in a multi-media environmental survey and to use the survey results to determine if residual lead from a once-active secondary lead smelter in Cairo, Egypt, still posed a health risk to the residents when comparing results with US EPA standards. Results were analyzed to determine if relationships among the variables indicated that there were residual impacts of the former smelter. Samples collected inside and near a total of 194 dwellings were analyzed. The mean floor dust lead loading was 7.48 μg lead/ft2. Almost 10% of the dwellings had at least one floor dust wipe sample that exceeded the United States Environmental Protection Agency's (USEPA) interior settled dust lead level of 40 μg lead/ft2. The median paint lead level was 0.04 mg lead/cm2. 17% of the dwellings had at least one interior paint sample that exceeded the USEPA standard of 1.0 mg lead/cm2. Mean soil lead concentration in the study area was 458 ppm and 91 ppm outside the study area. Four of nine composite soil samples exceeded the US EPA limit for bare soil in play areas. Lead concentrations in samples collected in locations outside the study area did not exceed the limit. The highest concentration was in the plot closest to the smelter and may represent residual impact from the former smelter. Statistically significant relationships were not detected between interior floor dust lead loading and either interior paint lead loading or exterior dust lead concentration. Thus, no significant exposure from the former smelter was indicated by these analyses. This may have resulted from the time elapsed since the closing of the smelter and/or the relatively low paint lead levels. Further study is needed in other areas of Egypt near former and active lead smelters. Elevated levels of mercury and arsenic detected in soil samples do not appear to be related to the smelter but warrant further study.
Lead concentrations in new enamel decorative paints were determined in three countries in different areas of the world where data were not previously available. The average total lead concentration of the enamel decorative paints purchased in Lebanon, Paraguay and Russia was 24,500ppm (ppm, dry weight), more than 270 times the current limit of 90ppm in Canada and in the United States. Sixty-three percent of these paints contained concentrations greater than 90ppm. Fifty-nine percent contained concentrations greater than 600ppm, the current limit in some countries. The maximum concentrations found were 236,000ppm in Lebanon, 169,000ppm in Paraguay and 52,900ppm in Russia. An average of 29% of the samples contained exceedingly high lead concentrations, >=10,000ppm. Five brands of paint were sampled in each of Lebanon and Paraguay and seven in Russia. Three colors from each brand were analyzed. For five of the six samples of the two brands in Lebanon with affiliations outside the country, the lead concentrations ranged from 1360ppm to 135,000ppm. In Lebanon the maximum concentration in the Egypt-affiliated brand (Sipes) was 135,000ppm and the maximum for the USA-affiliated brand (Dutch Boy) was 32,400ppm. Lead was not detected in any paints from the three of the four brands of paint purchased in Paraguay that had headquarters/affiliations in other countries (Brazil-Coralit), Germany (Suvinil) and USA (Novacor)). Two of the three paints from each of the other Paraguay brands contained high levels of lead with the maximum concentrations of 108,000 and 168,000ppm; one of these brands was manufactured under a license from ICI in the Netherlands. All of the paints purchased in Russia were from Russian brands and were manufactured in Russia. All three paints from one brand contained below detection levels of lead. The maximum levels of lead in the other six brands in Russia ranged from 3230 to 52,900ppm. The two brands with the highest lead concentration, TEKS and LAKRA, were produced by companies in the top three in market share.. Overall, lead concentrations were much higher in the colored paints such as red and yellow than in white paints. In each of the three countries a brand based in that country had a colored paint that either met a 90ppm limit or was close to meeting the limit-demonstrating that practical technology was available in each of these countries to produce low lead bright colored enamel decorative paints. Even though technology for producing paint without added lead existed in each of these countries, twenty-nine (29) percent of the paints analyzed contained exceedingly high concentrations (>=10,000ppm) of lead.
Paints with high lead concentrations (ppm) continue to be sold around the world in many developing countries and those with economies in transition representing a major preventable environmental health hazard that is being increased as the economies expand and paint consumption is increasing. Prior lead paint testing had been performed in Brazil and India and these countries were selected to examine the impact of a new regulatory limit in Brazil and the impact of efforts of non-governmental organizations and others to stop the use of lead compounds in manufacturing paints. Armenia and Kazakhstan, in Central Asia, were selected because no information on lead concentration in those regions was available, no regulatory activities were evident and non-governmental organizations in the IPEN network were available to participate. Another objective of this research was to evaluate the lead loading (µg/cm(2)) limit determined by X-Ray Fluorescence (XRF) for areas on toys that are too small to obtain a sample of sufficient size for laboratory analysis. The lead concentrations in more than three-fourths of the paints from Armenia and Kazakhstan exceeded 90 ppm, the limit in the United States, and 600 ppm, the limit in Brazil. The percentages were about one-half as high in Brazil and India. The average concentration in paints purchased in Armenia, 25,000 ppm, is among the highest that has been previously reported, that in Kazakhstan, 15,700 ppm, and India, 16,600, about median. The average concentration in Brazil, 5600 ppm, is among the lowest observed. Paints in Brazil that contained an average of 36,000 ppm before the regulatory limit became effective were below detection (< 9 ppm) in samples collected in the current study. The lack of any apparent public monitoring of paint lead content as part of regulatory enforcement makes it difficult to determine whether the regulation was a major factor contributing to the decline in lead use in these paints. Using data from the current study and those available from other studies 24 of 28 paints from major brands in India decreased from high concentrations to 90 ppm or lower. Since lead concentrations in golden yellow paints from these brands were found to decrease to ≤ 90 ppm, it is possible that all 28 of these paints now contain ≤ 90 ppm since yellow paints usually have the highest lead concentrations. Other brands in Brazil and India that have been analyzed only one time had lead concentrations up to 59,000 ppm and 134,000 ppm, respectively. Less than one-third of the paints had notations on their labels with information about lead content and these were sometimes inaccurate. The label from one brand indicating "no added lead" contained paint with 134,000 ppm lead, the highest found in this study. Three percent (3 of 98) of the paints with surface lead loading that did not exceed 2 µg/cm(2), the limit established by the Consumer Product Safety Improvement Act for small areas on toys, contained greater than 90 ppm lead and thus were false negatives. Of the new paint samples that contained ≤ 600 ppm, 88% contained ≤ 90 ppm. Of the samples that contained ≤ 90 ppm, 97% contained ≤ 45 ppm and 92% contained ≤ 15 ppm. Based on these data it appears to be technically feasible to manufacture paints containing ≤ 90 ppm and in many cases to produce paints that have lead concentrations that do not exceed 15 ppm.
The average total lead concentration of new enamel household paints in Egypt was previously reported to be the second highest among the seven countries from Africa, Asia and South America that were included in a 2009 publication.The follow up study reported in this paper includes more than twice as many brands (11 versus 4) and samples (45 versus 20) as the initial study.Paints from three of the four brands included in the initial study were sampled again to examine possible changes.Paint from the eight brands not examined in the initial study had lower lead concentrations (4,150 ppm average) compared to brands in the initial study, 26,200 ppm resulting in an average concentration of 11,900 ppm in the follow up study.These two averages are 291-and 132-times higher, respectively, than the current U.S. limit of 90 ppm in new paints for consumer use.Paint lead concentrations in brands/colors manufactured at different times did not exhibit any overall pattern of increase or decrease.The data from the follow up and initial studies were combined using the sample collected more recently for those brand/colors collected twice, resulting in a total of fifty-two (52) samples with an average lead concentration of 14,300 ppm.The presence of lead in new paints continues to represent a threat to children and efforts are needed to cease the use of lead compounds in making paints by using readily available substitutes.In a 1997 report of the analyses of fifteen (15) new paints intended for use on the interior of houses, the median concentration, 370 ppm, and the maximum, 19,200 ppm, were much lower than those presented in this report.This is consistent with a statement in the 1997 report that anecdotal evidence that some paint companies may be starting or increasing the production of lead-based paint.
Abstract The traditional method of determining dust lead loading (mass per unit area) on surfaces is to send dust wipe samples to a laboratory for analysis, and typically it takes one or more days to obtain results. Field-portable techniques taking 10 to 15 min for dust wipe lead analysis have been developed but need to be further evaluated. Dust wipe samples (n = 878) collected from a nationally representative sample of child care centers were tested by means of x-ray fluorescence (XRF) analysis with two XRF analyzer instrument models and subsequently analyzed for lead using flame atomic absorption spectrometry (FAAS). Samples were collected from floors and interior window sills and included blank and spiked quality control samples. Weighted linear regression was used to model the relationship between XRF and FAAS measurements. The correlations between FAAS and XRF measurements exceeded 0.80 (p < 0.0001). The highly significant statistical correlation suggests that the XRF method could be used to quantify dust lead loadings to determine compliance with dust lead hazard standards as defined by the U.S. Environmental Protection Agency. Small, but significant, differences in regression parameters were found between floor or sill and quality control sample types. The use of 95 % prediction intervals could allow for rapid screening of clearance samples in the field if method standards were developed. Additional work is needed in order for researchers to understand differences among XRF instruments and the conditions under which the use of XRF testing in the field could reduce the time or cost required in order to complete clearance testing.
Airborne exposure to manganese (Mn) can result in neurologic effects. Stationary air sampling is the traditional technique to assess Mn exposure for communities, yet may not accurately reflect children's personal exposure. The goal of the study was to characterize personal exposure to Mn and PM2.5 in a cohort of children ages 7-9 years residing near a ferromanganese refinery.A subset of children living in non-smoking households ages 7-9 enrolled in the Marietta Community Actively Researching Exposure Study during March-June 2009 and 2010 were invited to participate. Blood and hair were collected and analyzed for Mn. Participants wore a PM2.5 sampler (Personal Modular Impactor) for 48 h. TWD was based on time spent at home and school and the distance of each from the refinery. Stationary outdoor air sampling was conducted 8 km from the refinery using a Harvard-type PM2.5 impactor. The relationship between personal Mn exposure and TWD was examined by multiple regression adjusting for stationary air Mn concentration, wind speed and direction, and precipitation.Complete personal air sampling data were collected on 38 children. TWD ranged from 4.7 km to 28.5 km with a mean distance of 11.1 (4.7 sd) km. Mn concentration in personal air samples ranged from 1.5 ng/m(3) to 54.5 ng/m(3) (geometric mean, 8.1 ng/m(3)). TWD was a significant predictor of natural log personal air Mn concentration (InMn) with an associated decrease of 0.075 InMn for each km TWD (p<0.05, 95% CI -0.13 to -0.01). Personal Mn exposures were positively associated with stationary air Mn levels and inversely associated with wind speed. A child's location (home and school) relative to the refinery is a significant predictor of personal Mn exposure. Wind speed is also an important contributor to personal Mn exposure. (C) 2012 Elsevier B.V. All rights reserved.
Five brands of new enamel household paints from Taiwan were analyzed: two multi-nationals and three local. The median lead concentration of 2574 parts per million (ppm) dry weight was more than 30 times the current US standard of 90ppm for new paints and was more than 4 times the former standard of 600ppm. Lead levels ranged from below detection (4.5ppm) to 158,000ppm. Lead concentrations varied significantly by color of paint and paint brand but not by price per liter. Fifty-six percent of Taiwan paints had lead levels above the 90ppm US limit. One of the multi-national brands and two of the local brands had high levels of lead with the averages ranging from 12,890 to 53,640ppm. Concentrations were less than 90ppm in each of the samples from the other two brands. One of the two multi-national paint brands was imported as the house brand for its big box store in Taipei and had lead levels above 600ppm in four of five samples. Comparison of the lead concentrations of paints from Taiwan with those that we previously analyzed from mainland China revealed higher levels in Taiwan where the median level was 2574ppm compared to 46ppm in mainland China.
A 7-year follow-up was conducted to determine factors associated with the longevity of interim soil lead hazard control measures that had been applied to housing in the Cleveland OH area. The approach involved (1) visual determination of the treatment integrity, (2) collection of information regarding 14 factors that may contribute to longevity of treatment integrity and (3) collection of one composite soil sample from treated areas with visual failure at each house and another composite sample from areas without visual failure. For the 200 houses studied, an average of 4 different soil areas were treated. For 96% of these areas, the treatments used were: (1) re-seeding, (2) mulch/wood chips and (3) gravel. Of a total of 191,034ft2 of treated soil areas observed, less than one-third, i.e. 59,900ft2 (31.3%) exhibited visual failure at the time of follow-up. Hazard control method and the presence/absence of shade were the only factors found to significantly affect visual failure rates. Of the three most commonly used control measures, the lowest visual failure rate was for re-seeding, 29.1% after a mean of 7.3 years; for non-shaded areas, which had been re-seeded, the failure rate was 22.2% compared to 35.7% for shaded areas. At 116 of the 193 houses (60%) that had both visually failed and visually non-failed treated soil areas, the geometric mean soil lead concentration was higher in the failed areas (p=0.003). The actual difference was only 13% with most levels equal to or exceeding 400ppm. However, when compared to the US EPA limit for bare soil in other residential areas (1200ppm) the percent equal to or exceeding the limit was much higher in the visually failed areas, 33.1%, than in areas where such failure was not observed, 22.0%.
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 (7.0mg/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.
In 2006 a report on the analysis for lead in 80 new residential paints from four countries in Asia revealed high levels in three of the countries (China, India and Malaysia) and low levels in a fourth country (Singapore) where a lead in paint regulation was enforced. The authors warned of the possible export of lead-painted consumer products to the United States and other countries and the dangers the lead paint represented to children in the countries where it was available for purchase. The need for a worldwide ban on the use of lead in paints was emphasized to prevent an increase in exposure and disease from this very preventable environmental source. Since the earlier paper almost 300 additional new paint samples have been collected from the four initial countries plus 8 additional countries, three from Asia, three from Africa and two from South America. During the intervening time period two million toys and other items imported into the United States were recalled because the lead content exceeded the United States standard. High lead paints were detected in all 12 countries. The average lead concentration by country ranged from 6988 (Singapore) to 31,960 ppm (Ecuador). One multinational company sold high lead paint in one country through January 2007 but sold low lead paint later in 2007 indicating that a major change to cease adding lead to their paints had occurred. However, the finding that almost one-third of the samples would meet the new United States standard for new paint of 90 ppm, suggests that the technology is already available in at least 11 of the 12 countries to produce low lead enamel paints for domestic use. The need remains urgent to establish effective worldwide controls to prevent the needless poisoning of millions of children from this preventable exposure.
Manganese (Mn) is an essential element, yet is neurotoxic in excess. The majority of Mn research has been conducted on occupationally exposed adults with few studies focused on an environmentally exposed population. Marietta, OH is home to one of the largest airborne Mn emission sources in the United States, a ferromanganese refinery. In preparation for a community-based participatory research study, a preliminary pilot study was initiated to characterize the community's exposure to Mn in ambient air and to evaluate the relationship between biological indices of Mn exposure and genes associated with Mn metabolism in Marietta area residents. Participants in the pilot study were recruited through newspaper advertisement, fliers and direct mailing. Exposure to ambient Mn was estimated using an air pollution dispersion model, AERMOD. A total of 141 residents participated in the pilot study ranging in age from 2 to 81 years. Estimated annual average ambient air Mn concentrations in the study area obtained from AERMOD varied from 0.02 to 2.61μg/m3. Mean blood and hair Mn values were 9.12μg/L (SD 3.90) and 5.80μg/g (SD 6.40μg/g), respectively and were significantly correlated (r=0.30, p<0.01). Blood and hair Mn was significantly associated within families (r=0.27, p=<0.02 and r=0.43, p<0.01), respectively. The relationship between hair Mn and estimated ambient air Mn became significant when genes for iron metabolism were included in linear models. The preliminary ambient air and biological concentrations of Mn found in this population demonstrate the need for further research into potential health effects.
There is evidence in human populations that exposure to manganese (Mn), or Mn in combination with excessive noise exposure, results in hearing loss. Quantitative reverse‐transcriptase polymerase chain reaction revealed expression of the metal transporters DMT1, ZIP8, and ZIP14 in control mouse ears. ZIP8 is known to have a high affinity ( K m = 2.2 µM) for Mn transport, and ZIP8 protein was localized to the blood vessels of the ear by immunohistochemistry. We treated mice (strains C57BL/6J and DBA/2J) with Mn (100 mg/kg MnCl 2 , by subcutaneous injection, on three alternating days), and Mn was significantly elevated in the ears of the treated mice. Mn concentrations remained elevated over controls for at least 2 weeks after treatment. These studies demonstrate that metal transporters are present in the mouse ear and that Mn can accumulate in the ear following systemic exposure. Future studies should focus on whether Mn exposure is associated with hearing deficits. © 2008 Wiley Periodicals, Inc. J Biochem Mol Toxicol 22:305–310, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/jbt.20241
Children are at higher risk from lead exposure because their developing neural system is susceptible to its neurotoxic effects. We studied lead levels of paints manufactured in Nigeria in 2006. Lead levels in 5 colors of paints, each from different manufacturers were measured using flame-atomic absorption spectroscopy. We found that 96% of the paints had higher than recommended levels of lead. The mean lead level of paints ranged from 84.8 to 50,000 ppm, with mean of 14,500 ppm and median of 15,800 ppm. The main determinant of lead levels was color of the paint. As lead levels in paint sold in the past years in Nigeria are likely to be at least as high as that currently sold, it is likely that many existing houses contain dangerously high levels of lead. Efforts need to be undertaken to assess the presence of high lead levels in existing housing and if detected, intervention programs for eliminating risk of exposure should be developed in addition to measures to increase awareness and enforce regulations leading to the elimination of lead based domestic paint. © 2007 Elsevier B.V. All rights reserved.
Children are at higher risk from lead exposure because their developing neural system is susceptible to its neurotoxic effects. We studied lead levels of paints manufactured in Nigeria in 2006. Lead levels in 5 colors of paints, each from different manufacturers were measured using flame-atomic absorption spectroscopy. We found that 96% of the paints had higher than recommended levels of lead. The mean lead level of paints ranged from 84.8 to 50,000 ppm, with mean of 14,500 ppm and median of 15,800 ppm. The main determinant of lead levels was color of the paint. As lead levels in paint sold in the past years in Nigeria are likely to be at least as high as that currently sold, it is likely that many existing houses contain dangerously high levels of lead. Efforts need to be undertaken to assess the presence of high lead levels in existing housing and if detected, intervention programs for eliminating risk of exposure should be developed in addition to measures to increase awareness and enforce regulations leading to the elimination of lead based domestic paint.
Field portable methods are often needed in risk characterization, assessment and management to rapidly determine metal concentrations in environmental samples. Examples are for determining: "hot spots" of soil contamination, whether dust wipe lead levels meet housing occupancy standards, and worker respiratory protection levels. For over 30 years portable X-Ray Fluorescence (XRF) analyzers have been available for the in situ, non-destructive, measurement of lead in paint. Recent advances made possible their use for analysis of airborne dust filter samples, soil, and dust wipes. Research at the University of Cincinnati with the NITON 700 Series XRF instrument (40 millicurie Cadmium 109 source, L X-Rays) demonstrated its proficiency on air sample filters (NIOSH Method No. 7702, "Lead by Field Portable XRF; limit of detection 6 microg per sample; working range 17-1,500 microg/m3 air). Research with lead dust wipe samples from housing has also shown promising results. This XRF instrument was used in 1997 in Poland on copper smelter area soil samples with the cooperation of the Wroclaw Medical Academy and the Foundation for the Children from the Copper Basin (Legnica). Geometric mean soil lead concentrations were 200 ppm with the portable XRF, 201 ppm with laboratory-based XRF (Kevex) and 190 ppm using atomic absorption (AA). Correlations of field portable XRF and AA results were excellent for samples sieved to less than 125 micrometers with R-squared values of 0.997, 0.957, and 0.976 for lead, copper and zinc respectively. Similarly, correlations were excellent for soil sieved to less than 250 micrometers, where R-squared values were 0. 924, 0.973, and 0.937 for lead, copper and zinc, respectively. The field portable XRF instrument appears to be useful for the determination of soil pollution by these metals in industrial regions.
The final clean-up of residential lead abatement projects in federally-supported housing, as well as in other housing in a number of states, must meet surface dust lead clearance levels expressed as μg of lead per square foot. These clearance levels were established because hand-to-mouth ingestion of lead-contaminated dust is recognised as a major pathway through which many children are exposed. A dilemma exists because many floors in housing undergoing abatement are carpeted and the established clearance levels are generally not recommended for use on carpets. These clearance levels are also used as 'action levels' to determine whether exposure reduction activities are needed. The US Environmental Protection Agency is currently in the process of issuing standards for hazardous levels of lead in interior dust and bare soil under Title X of the Housing and Community Development Act of 1992, ‘The Residential Lead-Based Paint Hazard Reduction Act of 1992’. An effort to develop a potential surface dust lead clearance level for carpets was made using an existing vacuum dust collection method that has previously been shown to be a reliable indicator of childhood lead exposure. This method was designed for use on carpeted and non-carpeted surfaces. Using data from the Cincinnati Soil Lead Abatement Demonstration Project, the suggested floor-dust lead level where an estimated 95% of the population of children would be expected to have blood lead values below the national goal of 10 μg dL−1, was more than an order of magnitude lower than the current floor-dust lead clearance level of 1080 μg m−2 (100 μg ft−2). Further comparisons of blood lead and carpet lead levels in other parts of the country should be performed before a risk-based lead loading clearance level is established.
The U.S. Department of Housing and Urban Development (HUD) and several states have established floor and window dust lead clearance levels that must be met following lead-based paint abatement. These levels are also used as action levels to determine when exposure reduction measures are needed. Data are lacking on the relationship between these levels and the Centers for Disease Control (CDC) goal of having no more than 5 percent of children with blood lead levels above 10 μg/dl. Similarly, little information is available on the relationship between results using the HUD-prescribed surface wipe dust sampling method and a vacuum dust collection method utilizing a personal air sampling pump as a vacuum source, which has been used in a number of lead exposure studies. Blood lead, paint lead, and floor dust lead levels by both methods from 53 households in a mining community with lead paint sources were examined to help answer these questions. Results suggest that the HUD floor clearance level may not be low enough to achieve the CDC childhood blood lead goal. The two dust collection methods were found to be statistically correlated. Vacuum dust lead was correlated to paint lead, but wipe dust lead was not.