Direct Environmental Lead Detection by Photoluminescent Perovskite Formation with Nanogram Sensitivity.

Although the global ban on leaded gasoline has markedly reduced lead poisoning, many other environmental sources of lead exposure, such as paint, pipes, mines, and recycling sites remain. Existing methods to identify these sources are either costly or unreliable. We report here a new, sensitive, and inexpensive lead detection method that relies on the formation of a perovskite semiconductor. The method only requires spraying the material of interest with methylammonium bromide and observing whether photoluminesence occurs under UV light to indicate the presence of lead. The method detects as little as 1.0 ng/mm2 of lead by the naked eye and 50 pg/mm2 using a digital photo camera. We exposed more than 50 different materials to our reagent and found no false negatives or false positives. The method readily detects lead in soil, paint, glazing, cables, glass, plastics, and dust and could be widely used for testing the environment and preventing lead poisoning.

Pathways and sources of lead exposure: Michigan Children's Lead Determination (the MI CHILD study).

There has been little research on childhood lead exposure pathways since the 1990s. New data from Michigan in 2017-2021 for 429 children in 345 homes included lead in blood, paint, dust, soil, water, and other housing, demographic, and behavioral metrics. Fifty-three percent of these children had blood lead (BPb) ≥5 µg/dL. A repeated measures pathway model that accounted for multiple children in the same home was constructed using weighted least squares mean estimation and included variance-covariance model multiple imputation. Results showed that children's BPb was directly predicted by lead in settled floor house dust, child's age, season, and mouthing behavior and indirectly predicted by window sill and trough dust lead (DPb), bare soil lead (SPb), proportion of floors with carpets, and exterior building deteriorations. Paint lead (PPb) was also an indirect predictor of BPb through the soil and settled dust pathways. Water lead (WPb), water consumption and other lead sources/pathways were not significant predictors of BPb in this cohort. Although risk factors for individual children are highly variable and worthy of investigation to pinpoint their exposures, this study shows that the main direct and indirect pathways of lead exposure for most children in older housing remain paint and the contaminated dust and soil it generates. Pathway analyses in other jurisdictions using current data should be performed to confirm these results. This study suggests both DPb and BPb in high-risk homes may have declined since the 1990s and that lead in dust, soil, and paint all should be measured to predict risk and target remediation. Because most homes still have not been assessed for lead hazards and remediated, too many children remain at needless risk.

Total lead concentration in new decorative enamel paints in Lebanon, Paraguay and Russia.

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.

Lead in new paints in Nepal.

Samples from 75 paint products made by 21 domestic and foreign manufacturers were purchased from retail stores in five major cities in Nepal and tested for lead content. Information provided on product labels were noted. Samples were selected to be representative of the large number of brands and colors available in retail shops. Although a majority of the products purchased were manufactured in Nepal, paints from four additional countries were tested. Out of a total of 75 samples, 57 (76%) of the tested paints contained lead at concentrations greater than 90 ppm (ppm). Ninety-three percent of the paints that exceeded 90 ppm had levels in excess of 600 ppm. Lead concentrations in the tested paints ranged up to 200,000 ppm (20%) lead by weight and the median concentration was 5100 ppm. These results indicate that lead paint is commonly being sold for residential and other consumer applications in Nepal without any consumer warnings. Regulations are needed to specify the maximum concentration of lead allowed in paint products manufactured, imported, or distributed in the country to protect public health. Efforts must be made to get lead-containing paint products recalled from stores so that they are not used in homes, schools, and other child-occupied facilities.

Lead levels of new solvent-based household paints in Zimbabwe and Botswana: A preliminary study.

BACKGROUND: Lead paint remains a major potential source of lead poisoning globally, but there has been no documentation on lead content in solvent paints available on the markets in Zimbabwe and Botswana. AIM: To determine the lead content of solvent-based paints available on the market in Zimbabwe and Botswana and identify a need for a larger study to inform policy. METHODS: This pilot study was conducted in Harare, Zimbabwe, and Gaborone, Botswana. Popular brands of solvent-based household paints were bought from hardware shops in Harare (10 samples) and Gaborone (19 samples). Samples were analysed for lead content using inductively coupled plasma-atomic emission spectrometry. RESULTS: Seventy percent of samples from Zimbabwe were found to contain lead above 90 parts per million (ppm), the recommended regulatory limit, with ranges from less than 60 ppm to 12 000 ppm. Twenty percent of Zimbabwean samples had lead levels above 10 000 ppm. No samples from Botswana had lead concentration above the detection limit, with all levels below 100 ppm. LESSON LEARNT: Data strongly suggest very high lead content in popular brands of solvent paints in Zimbabwe, indicating a need for a larger, well-designed study for policy direction.

Insights into the Slow Uptake of Residential Lead Paint Remediation Funds: A Lancaster, Pennsylvania, Case Study.

Lead poisoning is a preventable condition that continues to affect thousands of children each year. Given that local governments and municipalities are eligible to apply for federal funds to perform lead remediation in low-income family homes, we sought to understand how lead poisoning knowledge levels may affect the uptake of these funds. We recruited and conducted 28 in-depth, semi-structured interviews with community members from Lancaster County in the state of Pennsylvania in the USA. We audio-recorded and transcribed each interview, and analyzed each transcript for salient themes. The interviewed participants displayed a varying degree of knowledge about lead and lead poisoning. Most of the participants were unaware of the lead paint remediation funds. Participants learned about lead from various sources, such as social media, and personal experiences with lead poisoning appeared to enhance knowledge. Some participants assumed lead poisoning prevention would be addressed by other stakeholders if necessary, including healthcare professionals and landlords. The results of this study suggest that in order to increase the timely uptake of the remediation funds, community-based organizations should design interventions that aim to increase awareness and knowledge about lead poisoning and lead poisoning prevention. These interventions should be tailored for different audiences including community members, healthcare professionals, and landlords.

The State of Public Health Lead Policies: Implications for Urban Health Inequities and Recommendations for Health Equity.

Although lead has been removed from paint and gasoline sold in the U.S., lead exposures persist, with communities of color and residents in urban and low-income areas at greatest risk for exposure. The persistence of and inequities in lead exposures raise questions about the scope and implementation of policies that address lead as a public health concern. To understand the multi-level nature of lead policies, this paper and case study reviews lead policies at the national level, for the state of California, and for Santa Ana, CA, a dense urban city in Southern California. Through a community-academic partnership process, this analysis examines lead exposure pathways represented, the level of intervention (e.g., prevention, remediation), and whether policies address health inequities. Results indicate that most national and state policies focus on establishing hazardous lead exposure levels in settings and consumer products, disclosing lead hazards, and remediating lead paint. Several policies focus on mitigating exposures rather than primary prevention. The persistence of lead exposures indicates the need to identify sustainable solutions to prevent lead exposures in the first place. We close with recommendations to reduce lead exposures across the life course, consider multiple lead exposure pathways, and reduce and eliminate health inequities related to lead.

Letter to the Editor Re: Andrew Turner, Emily R. Kearl, Kevin R. Solman Lead and other toxic metals in playground paints from South West England Science of the Total Environment 544 (2016) 460-466.

Turner's paper emphasizes "oral bioaccessibility" instead of focusing solely on total lead content. There is no evidence that solubility testing for lead levels in paint correlates with absorption or blood lead levels in exposed children. There are many considerations in determining exposure hazards to paint that are not evaluated in assessing solubility. Although we strongly support the conclusions and recommendations of the study, we are concerned that by reporting "oral bioaccessibility" others will focus on solubility in developing regulatory standards for lead levels in paint or in conducting exposure assessments. Standards for lead in paint should continue to be based on total lead content, not "oral bioaccessibility."