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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/ft(2). 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/ft(2). The median paint lead level was 0.04 mg lead/cm(2). 17% of the dwellings had at least one interior paint sample that exceeded the USEPA standard of 1.0 mg lead/cm(2). 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.

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., (Copyright © 2014 Elsevier Inc. All rights reserved.)

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 31,960ppm (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 90ppm, 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.

The US Department of Housing and Urban Development (HUD) undertook an evaluation of its Lead Hazard Control Grant Program between 1994 and 1999. The Evaluation is the largest study ever done on the effectiveness of lead hazard controls implemented in residential dwellings. The Evaluation had several major objectives: determining the effectiveness of various lead hazard controls in reducing residential dust lead levels and children's blood lead levels, establishing the costs of doing lead hazard control work and factors that influence those costs, determining the rate of clearance testing failures and their causes, and identifying possible negative effects of lead hazard control work on children's blood lead levels. This paper reports the overall research design and data collection methods of the Evaluation. The large number of dwelling units enrolled in the Evaluation was possible only by the innovative partnership among HUD, the Evaluators, and the grantees. HUD and the Evaluators relied on the grantees for essentially all of the data collection. The 14 participating HUD Lead Hazard Control Grantees were responsible for implementing the lead hazard control programs in their communities and collecting the study data. This paper describes the methods for recruiting and enrolling dwellings and families, collecting environmental and housing data, interviewing participating families, and collecting data on lead hazard control work performed and its costs. The paper also describes the basic quality control and quality assurance procedures used. The principal outcome measures were lead in dust collected using wipes from floors, window sills, and window troughs and lead in blood collected from children who were 6 years old or younger at enrollment. Data collection was conducted before intervention, immediately postintervention, and 6 and 12 months postintervention. For a subset of dwellings undergoing an extended follow-up data were also collected at 24 and 36 months postintervention. This paper provides the context for subsequent reports that will describe such findings as the influence of lead hazard control work on serial dust lead levels, the influence of lead hazard control work on serial blood lead levels in children, the nature and costs of the lead hazard control work done at the dwellings, and the experience of the grantees in meeting clearance testing requirements.

To aid in understanding the contribution of exterior dust/soil lead to postintervention interior dust lead, a subset of housing from the HUD Lead-Based Paint Hazard Control Grant Program Evaluation was selected for study. Housing from 12 state and local governments was included. Exterior entry and street dust samples were obtained by a vacuum method, and soil samples were building perimeter core composites. Interior dust wipe lead data (microg/ft(2)) and paint lead data (mg/cm(2)) were also available for each of the dwelling units and included in the modeling. Results from 541 dwelling units revealed a wide range of exterior dust and soil lead levels, within and between grantees. Minimum and maximum geometric mean lead levels, by grantee, were 126 and 14400 microg/ft(2) for exterior entry dust; 325 and 4610 microg/ft(2) for street dust; and, for soil concentration, 383 and 2640 ppm. Geometric mean exterior entry dust lead concentration (1641 ppm) was almost four times as high as street dust lead concentration (431 ppm), suggesting that lead dust near housing was often a source of street dust lead. Geometric mean exterior entry dust lead loading was more than four times as high as window trough dust lead loading and more than an order of magnitude higher than interior entry dust lead loading. Statistical modeling revealed pathways from exterior entry dust lead loading to loadings on interior entryway floors, other interior floors, and windowsills. Paint lead was found to influence exterior entry dust lead. Results of this study show that housing where soil lead hazard control activities had been performed had lower postintervention exterior entry, interior entry floor, windowsills, and other floor dust loading levels. Soil was not present for almost half the buildings. Statistical analysis revealed that exterior strategy influenced soil lead concentration, and soil lead concentration influenced street dust lead loading. This study represents one of the few where an impact of soil treatments on dust lead levels within the housing has been documented and may represent the first where an impact on exterior entry dust lead has been found. The inclusion of measures to mitigate the role of exterior sources in lead hazard control programs needs consideration.

Data from an evaluation of the HUD Lead Hazard Control Grant Program were used to evaluate the prevalence and location of teeth marks on painted surfaces in residential housing. The results of these analyses will be useful in the development of more effective pediatric lead poisoning prevention programs. These programs have historically placed considerable emphasis on surfaces accessible to children for mouthing activities. This study analyzes the largest set of data ever assembled on the prevalence of teeth marks in housing. Data from 308,851 observations in 3,454 housing units were analyzed to determine the prevalence of teeth mark observations per surface, dwelling unit, and building component, and by housing age, inspector, and grantee. An average of 4.0 teeth marks per 10,000 surfaces with paint-lead greater than or equal to 1.0 mg/cm2 were observed. For surfaces with less than 1.0 mg/cm2 lead the rate was 1.5 teeth marks/10,000 surfaces. The number of teeth marks per 10,000 surfaces increased with age of housing for surfaces with 1.0 mg/cm2 or higher lead but not for surfaces with less than 1.0 mg/cm2 lead. Teeth mark observation rates were 36 times higher for windowsills than for other components and ranged up to 11 per 10,000 surfaces and 9 dwellings per 100 dwelling units for 2 grantees with the highest rates. Blood lead levels in children exhibiting moderate to high mouthing behavior were higher than in children without such behavior, especially in housing where teeth marks were observed. Special priority should be given to windowsills when making decisions on lead hazard control for "accessible," "chewable," or "mouthable" surfaces.

Quantifying airborne lead on lead abatement work sites is critical in assessing worker lead exposures. Airborne lead levels depend on both the concentration of aerosolized particles and the percent lead in those particles. The lead level on the painted surface being abated may affect the percent lead in aerosolized particles. Experiments were performed in the University of Cincinnati Environmental Test Chamber (volume approximately 24.3 m3) using wood doors painted with lead-based paint. Three methods were used for paint removal: dry scraping, wet scraping, and dry machine sanding. Particles aerosolized during lead abatement activities were collected on filters using the Button Personal Inhalable Aerosol Samplers (SKC Inc., Eighty Four, PA) mounted in the workers' breathing zone. The filters were subsequently analyzed for percent lead in the particles. A portable X-ray fluorescence (XRF) instrument (NITON-700, NITON Inc., Bedford, MA) was used to measure surface lead levels of the doors. The accuracy of the XRF instrument was verified by testing standard reference materials prepared by the National Institute of Standards and Technology (NIST) and by Princeton Gamma Tech Inc. It was also verified by relating XRF results from painted door surfaces to laboratory lead analysis data obtained from paint chip samples taken from the same painted surfaces (r2 = 0.81, p < 0.001). A highly significant relationship (r2 = 0.83, p < 0.001) was found between the XRF readings and the percent lead in the particles aerosolized during dry scraping. No significant relationship was found for wet scraping (r2 = 0.09, p = 0.56) or dry machine sanding (r2 = 0.002, p = 0.92). The relationship between surface lead levels and percent lead in particles was found to be dependent on the paint removal method. This variation was attributed to the difference in water absorption property of the paint layers and the different particle aerosolization mechanisms inherent in each paint removal method.

The effectiveness of procedures used for the final indoor cleaning after active lead-based paint abatement were evaluated in a 830 ft3 test chamber. Dry and wet scraping and dry machine sanding were applied to wooden doors obtained from lead-hazard control sites. The airborne particle concentration and size distribution were monitored using a real-time particle size spectrometer. Particulates were also collected on filters and analyzed for total dust and lead. The resulting airborne lead mass was determined for each cleaning procedure, and the potential floor lead loading resulting from the dust settling was calculated. Wipe samples were collected to measure the actual floor lead loading. The effectiveness of final cleaning was evaluated first for dry abatement methods. Various cleaning work practices were tested by applying wet and dry debris sweeping as well as no sweeping in combinations with wet and dry removal of plastic sheeting. Considerable resuspension of leaded particles was detected during dry sweeping: the airborne lead mass increase ranged between 65 and 220 percent. However, this increase did not exceed 22 percent when wet sweeping was applied. Minimal or no resuspension was found when the plastic was folded with leaded debris inside (no sweeping was performed prior to the sheeting removal). During folding activity, the "clean" (uncovered) floor surface may be significantly contaminated with leaded dust from workers' shoes and cleaning tools. The first HEPA vacuuming resulted in a 15- to 20-fold decrease of the airborne lead mass; however, it was not sufficient to reduce the floor lead loading to the U.S. Department of Housing and Urban Development (HUD) clearance level of 40 microg/ft2, as determined by wipe sampling. Wet mopping following the first HEPA vacuuming was proven to be effective to reduce the lead loading significantly below 40 microg/ft2. The second HEPA vacuuming resulted in further reduction of the airborne lead mass concentration. The floor lead loading remained much lower than 40 microg/ft2. These results were confirmed in the tests when using wet scraping. Overall, the HUD-recommended cleaning protocol was found to be sufficient in reducing the floor lead loading below 40 microg/ft2. At the same time, several modifications are proposed in this study to further improve the cleaning effectiveness.