Lead Exposure In Children Research Articles

Presence and concentration of lead in keys and keyring items.

Environmental lead is a persistent hazard that disproportionately affects children. Keys are known sources of lead exposure in children, but little is known about the specific lead content or frequency of lead in keys. We identified differences in lead concentration and frequency across items with different physical characteristics. This study tested a convenience sample of keys and keychain objects using an X-ray Fluorescence (XRF) analyzer. The mean lead concentration across 362 objects tested was 1722 ppm (SD 3657 ppm; range 95.5-44 400 ppm). Lead was present in the majority (64%) of objects tested. Door keys had the highest concentration of lead (mean 2646 ppm; SD 3701 ppm). Door keys had significantly more lead than both vehicle keys (p<0.0001) and electronic fobs (p=0.0004). Gold-coloured keys contained significantly more lead than silver-coloured keys (p<0.0001). Copied keys were significantly more likely to contain detectable levels of lead compared with original keys (p<0.0001); however, this relationship was not significant when controlling for key type. There was a positive association between key age and lead concentration (p=0.009). Keys were less likely to contain lead if they were silver-coloured; car keys or electronic fobs; and newer. However, several categories of keys with less lead contained high lead levels, and the majority of items tested (64%) contained more lead than limits on lead in keys that were implemented in Minnesota after data collection (90 ppm). The levels of lead identified highlight the need for public education and potential additional regulatory guidelines for keys.

Recently Recalled Children's Products Due to Lead Hazards.

We reviewed recent reports of recalled children's products contaminated with lead to learn more about what could be done to inform public health partners about the recalls in a timely manner to assist with broader consumer notification for proactive lead poisoning prevention efforts. Centers for Disease Control and Prevention staff reviewed lead-related recall notices for children's products issued during June 2022 through April 2024. Recall notices were extracted from the Consumer Product Safety Commission using Really Simple Syndication feed technology to identify and capture the most current recall information. Specific product details in the database were extracted and analyzed descriptively to identify response trends and best practices. Centers for Disease Control and Prevention's automated tool identified 30 recalls from Consumer Product Safety Commission. Lead-contaminated toys were the most frequent type of product recalled (n = 11, 37%). Most products were manufactured in China (n = 24, 86%). Products were on the market for an average of 25 months before they were recalled. No injuries were reported. The 30 recalls resulted in a combined number of 914 598 recalled units sold. The current approach to protecting children from lead hazards in consumer products could be augmented by timely notifying the public health community about recalls so they can broadly disseminate information through their channels to reduce lead exposure in children. Additional steps to reduce lead contamination in children's products when sourcing raw materials and components may help to decrease the number of recalls.

Perspectives on Childhood Lead Exposure Prevention: Looking Back and Looking Ahead.

Lead's neurotoxic properties and potential harmful effects to humans, particularly young children, have been recognized for decades, influencing public health policies to reduce its admixture in house paint and passenger car gasoline. We signal 3 emergent trends: firearm proliferation, complex international food supply chains, and equally complex product marketing strategies, which have opened opportunities for lead exposure to children from guns and ammunition, and lead contamination in children's food and consumer goods. Readers will also be apprised of Childhood Lead Poisoning Prevention Program and education strategies cultivated and advanced by the Centers for Disease Control and Prevention and its lead prevention partners. A national governmental policy update is included, as are future considerations.

State-Level Childhood Lead Poisoning Prevention Policies and Practices in the United States: 2022-2023.

The purpose of this analysis is to better understand laws and practices guiding prevention activities in childhood lead poisoning prevention programs funded by the Centers for Disease Control and Prevention (CDC). In 2022, CDC surveyed 62 funded programs using the Awardee Lead Profile Assessment. Information was collected about childhood lead poisoning-related laws and guidance, surveillance and prevention strategies, and program services including at what blood lead levels (BLLs) various activities are performed. Separately, CDC reviewed state health department websites to obtain information on which states implemented CDC's updated blood lead reference value. Awardee Lead Profile Assessment results are only reported for 47 states, the District of Columbia, and Puerto Rico. Almost all programs (96%) have laws requiring reporting of BLLs, and 51% require BLLs be reported electronically to jurisdictional health departments. Most programs (80%) prioritize areas and populations that are high risk for lead poisoning prevention activities. Approximately half of the programs (51%) have a lead elimination plan or goal. Thirty-nine percent of the programs have already implemented policies, laws, or regulations to achieve lead elimination, and 74% are in the Northeast and Midwest regions of the country. As of March 2023, 71% of the programs have implemented CDC's updated blood lead reference value, and most (65%) did so via guidance for health care providers and laboratories for what BLL should initiate case management and other services for lead-exposed children. Almost all programs have mandatory BLL reporting laws, and about two-thirds of the programs updated their BLLs that trigger public health action.

Childhood lead exposure and sleep problems in adolescents: a longitudinal cohort study.

Childhood lead exposure is linked to poorer neurobehavioral function in adolescence, but the relationship between lead and adolescent sleep health remains inconsistent. This study aimed to investigate concurrent and longitudinal associations between lead exposure and multiple sleep health domains in adolescents. A total of 972 adolescents from China Jintan Child Cohort were included in analyses. The Blood lead levels (BLLs) were assessed in two Waves, at ages 3-5years (mean 6.50 ± 2.76μg/dL) and 11-13years (mean 3.12 ± 1.17μg/dL). Sleep problems at age 11-13 were parent-reported via the Child Sleep Health Questionnaire (CSHQ) and self-reported by adolescents using the Pittsburgh Sleep Quality Index (PSQI). Both early and later BLLs were associated positively with parental reported sleep problems, including sleep onset delay, night waking, short duration, parasomnias, and disordered breathing. Sex-stratified analyzes showed that most adjusted associations between two-Wave BLLs and sleep outcomes (CSHQ and PSQI) remained statistically significant in males, with a minor increase in the magnitude of these associations. The association between Wave II BLLs and shorter self-reported sleep duration was only statistically significant in female adolescents. Compared to children with consistently low BLLs at both ages, those with persistently high BLLs at both ages had significantly shorter parental-reported sleep duration and worse sleep onset delay. Findings suggest that both early and later childhood lead exposures link to more adolescent sleep problems, with recent BLLs showing stronger associations with poor adolescent sleep health reported by their parents.

Spatial Variability in Relationships between Early Childhood Lead Exposure and Standardized Test Scores in Fourth Grade North Carolina Public School Students (2013-2016).

Exposure to lead during childhood is detrimental to children's health. The extent to which the association between lead exposure and elementary school academic outcomes varies across geography is not known. Estimate associations between blood lead levels (BLLs) and fourth grade standardized test scores in reading and mathematics in North Carolina using models that allow associations between BLL and test scores to vary spatially across communities. We link geocoded, individual-level, standardized test score data for North Carolina public school students in fourth grade (2013-2016) with detailed birth records and blood lead testing data retrieved from the North Carolina childhood blood lead state registry on samples typically collected at 1-6 y of age. BLLs were categorized as: (reference), , and . We then fit spatially varying coefficient models that incorporate information sharing (smoothness), across neighboring communities via a Gaussian Markov random field to provide a global estimate of the association between BLL and test scores, as well as census tract-specific estimates (i.e., spatial coefficients). Models adjusted for maternal- and child-level covariates and were fit separately for reading and math. The average BLL across the 91,706 individuals in the analysis dataset was . Individuals were distributed across 2,002 (out of 2,195) census tracts in North Carolina. In models adjusting for child sex, birth weight percentile for gestational age, and Medicaid participation as well as maternal race/ethnicity, educational attainment, marital status, and tobacco use, BLLs of , and were associated with overall lower reading test scores of [95% confidence interval (CI): , ], (, ), and (, ), respectively. For BLLs of , , and , spatial coefficients-that is, tract-specific adjustments in reading test score relative to the "global" coefficient-ranged from to 2.52, to 3.90, to 7.85, and to 4.33, respectively. Results for mathematics were similar to those for reading. The association between lead exposure and reading and mathematics test scores exhibits considerable heterogeneity across North Carolina communities. These results emphasize the need for prevention and mitigation efforts with respect to lead exposures everywhere, with special attention to locations where the cognitive impact is elevated. https://doi.org/10.1289/EHP13898.

Structural Racism in Adverse Health Outcomes from Childhood Lead Exposure in Philadelphia

Structural Racism in Adverse Health Outcomes from Childhood Lead Exposure in Philadelphia

Tracking Childhood Lead Exposure in Early Industrial Romanians

Childhood lead exposure has been linked to severe adverse health outcomes throughout life. Measurements of lead in teeth have established that individuals living in contaminated environments show higher levels compared to individuals living further away, although less is known about when individuals are most susceptible to these exposures. We examined lead (Pb208) concentrations (ppm) in teeth over the first 2.5 years of life in 16 children born in the late 19th to early 20th century throughout Romania. This period of intense industrialization was characterized by increases in mining, coal burning, and oil refining—activities that contaminate air, water, and food with Pb. We hypothesized the distance from an operational mine or oil refinery, or being born in a city, would be positively associated with cumulative dentine Pb exposure (CDPE). We also predicted that Pb exposures would peak in the first six months of life when gastrointestinal (GI) absorption of Pb is likely highest. Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) of sectioned tooth dentine followed by Bayesian statistical analyses revealed that living 30 km or more from a mine or oil refinery did not explain CDPE. However, being born in a city explained 42% of CDPE. All individuals showed maximum Pb exposures after six months of age, likely due to contaminated solid food and/or non-milk liquids. This research demonstrates how tooth formation can be coupled with comprehensive elemental mapping to analyse the context and timing of early-life neurotoxicant exposures, which may be extended to well-preserved teeth from clinical and historic populations.

Childhood Lead Exposure Linked to Apple Cinnamon Fruit Puree Pouches - North Carolina, June 2023-January 2024.

Lead exposure is toxic even at low levels, resulting in impairments that can affect a child's lifelong success. In North Carolina, testing for lead is encouraged for all children at ages 1 and 2 years and required for children covered by Medicaid; investigations are performed to identify potential exposure sources for children with blood lead levels (BLLs) ≥5 μg/dL. During June-August 2023, routine lead testing identified four asymptomatic North Carolina children with BLLs ≥5 μg/dL. Home investigations identified only WanaBana brand apple cinnamon fruit puree pouches as a potential exposure source; product samples contained 1.9-3.0 ppm of lead. An expanded nationwide investigation led to identification of approximately 500 cases of childhood lead exposure believed to be linked to consumption of apple cinnamon purees, including 22 cases in North Carolina. Fewer than one half (45%) of the 22 North Carolina cases were among children covered by Medicaid. A coordinated multiagency communication strategy was implemented in North Carolina to notify consumers of the hazard and provide recommendations for preventing further exposure. The Food and Drug Administration issued a nationwide public health advisory on October 28, 2023; 2 days later, the manufacturer issued a voluntary recall. Routine testing of young children for lead exposure, combined with thorough environmental investigations, can identify emerging sources of lead exposure and limit further harm.

Comparison of empirical and mechanistic blood lead models for children

Childhood exposure to lead can result in increased blood lead levels, which can have detrimental health effects. Models that can predict blood lead level based on exposure to floor and window sill dust lead at varying concentrations are useful tools for informing policy decisions. We compare an empirical model relating blood lead in children to the lead content of household dust, with a mechanistic model that simulates lead exposure in children through their daily activities. The empirical model is constructed using 1999–2004 NHANES data, while the mechanistic model is validated using 2011–2016 NHANES data. The models are evaluated at dust loadings ranging from 0.18 – 43 µg/ft2 and the resulting blood leads are compared. Specific demographic variables are chosen to simulate individuals are generated with “typical,” “high end,” and “low end” exposures in the empirical model; these are directly compared with the median, 95th, and 5th percentile results from the mechanistic model. For a child with “typical” lead exposure, the 95 % confidence interval for computed blood lead values contained the median blood lead value from the mechanistic model at all dust lead exposure levels considered. Similar results hold when comparing the 95th percentile to “high end” and 5th percentile to “low end”. The blood lead level computed by the mechanistic model increases more quickly with respect to dust loading than the empirical model, particularly at higher loadings. The empirical and mechanistic models generate similar blood lead distributions across the range of dust loadings considered, particularly at low loadings. The mechanistic model may be more appropriate for higher loadings due to limitations inherit in the structure of the empirical model.

House Sparrows as Sentinels of Childhood Lead Exposure.

Our understanding of connections between human and animal health has advanced substantially since the canary was introduced as a sentinel of toxic conditions in coal mines. Nonetheless, the development of wildlife sentinels for monitoring human exposure to toxins has been limited. Here, we capitalized on a three-decade long child blood lead monitoring program to demonstrate that the globally ubiquitous and human commensal house sparrow (Passer domesticus) can be used as a sentinel of human health risks in urban environments impacted by lead mining. We showed that sparrows are a viable proxy for the measurement of blood lead levels in children at a neighborhood scale (0.28 km2). In support of the generalizability of this approach, the blood lead relationship established in our focal mining city enabled us to accurately predict elevated blood lead levels in children from another mining city using only sparrows from the second location. Using lead concentrations and lead isotopic compositions from environmental and biological matrices, we identified shared sources and pathways of lead exposure in sparrows and children, with strong links to contamination from local mining emissions. Our findings showed how human commensal species can be used to identify and predict human health risks over time and space.

Validation of a low-cost lead hazard screening kit for the home environment.

The main sources of lead exposure for children occur in the home environment, yet no low-cost analytical methods exist to screen homes for lead hazards. Previously, an inexpensive (~$20), quantitative lead screening kit was developed in which residents collect soil, paint, and dust samples that are returned to a laboratory for lead analysis using X-ray fluorescence spectroscopy (XRF). This screening kit was initially validated in 2020; it was determined that in situ and ex situ XRF lead measurements on the same samples exhibited strong sensitivity, specificity, and accuracy. As a follow-up to the initial validation, an implementation study and further statistical analyses were conducted. Correlation analysis using the results from nearly 400 screening kits identified an overall lack of correlation between sample types, reinforcing the utility of all eight sample locations. Principal component analysis searched for underlying correlations in sample types and provided evidence that both interior and exterior paint are major sources of lead hazards for Indiana homes. The implementation study compared the results of the government-standard lead inspection and risk assessment (LIRA) and the lead screening kit in 107 Indiana homes. In the United States, the LIRA is a thorough inspection of paint, dust, and soil that is usually state mandated in response to a child's elevated blood level and is used to identify where remediation efforts should be focused. The lead screening kit and LIRA agreed on the presence of lead in 79 of the 107 homes tested (74%). Discrepancies in agreement are likely the result of differences in the sample location and number of samples collected by each method. Overall, these results suggest that the lead screening kit is an acceptable resource that could be used to expand the services health departments provide for lead prevention. Integr Environ Assess Manag 2024;20:1504-1513. © 2024 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Estimated Childhood Lead Exposure From Drinking Water in Chicago

There is no level of lead in drinking water considered to be safe, yet lead service lines are still commonly used in water systems across the US. To identify the extent of lead-contaminated drinking water in Chicago, Illinois, and model its impact on children younger than 6 years. For this cross-sectional study, a retrospective assessment was performed of lead exposure based on household tests collected from January 2016 to September 2023. Tests were obtained from households in Chicago that registered for a free self-administered testing service for lead exposure. Machine learning and microsimulation were used to estimate citywide childhood lead exposure. Lead-contaminated drinking water, measured in parts per billion. Number of children younger than 6 years exposed to lead-contaminated water. A total of 38 385 household lead tests were collected. An estimated 68% (95% uncertainty interval, 66%-69%) of children younger than 6 years were exposed to lead-contaminated water, corresponding to 129 000 children (95% uncertainty interval, 128 000-131 000 children). Ten-percentage-point increases in block-level Black and Hispanic populations were associated with 3% (95% CI, 2%-3%) and 6% (95% CI, 5%-7%) decreases in odds of being tested for lead and 4% (95% CI, 3%-6%) and 11% (95% CI, 10%-13%) increases in having lead-contaminated drinking water, respectively. These findings indicate that childhood lead exposure is widespread in Chicago, and racial inequities are present in both testing rates and exposure levels. Machine learning may assist in preliminary screening for lead exposure, and efforts to remediate the effects of environmental racism should involve improving outreach for and access to lead testing services.

Identifying High-Risk ZIP Codes for Childhood Lead Exposure: A Statewide ZCTA-Level Priority List for North Carolina.

Research has consistently shown that there is no safe blood lead level (BLL) for children. Despite progress in lead poisoning prevention, lead exposure remains a persistent threat to the health and neurological development of children. To identify high-risk ZIP codes for use by families and health care providers for the entire state of North Carolina, we developed a risk model using ZIP Code Tabula-tion Area (ZCTA)-level census data. We obtained all available BLL testing data from the North Carolina Department of Health and Human Services for the years 2010-2015 via data use agreement. We fit a multivariable regression model with the ZCTA-level mean of log normalized BLLs as the de-pendent variable and ZCTA-level census data for known risk factors of childhood lead exposure as predictors. We used this model to create a priority risk categorization. We organized ZCTAs into 20 quantiles, or priority risk categories, that can be used in local and statewide screening programs. The first six (of 20) quantiles were identified as particularly high-risk areas for childhood lead exposure. Because BLL testing is not universal, the BLL testing data used in this study are likely biased toward those most at risk for lead exposure. This study demonstrates the utility of ZCTA-level census data in identifying high-risk ZIP codes for childhood lead exposure, which can be used to ensure that the highest-risk children are tested in a timely manner. This approach can be replicated to address lead exposure nationally.

Prenatal and early life lead exposure induced neurotoxicity.

Lead (Pb) has become a major environmental contaminant. There are several ways in which lead can enter the human body and cause toxic effects on human health. This review focuses on the impact of lead toxicity at prenatal and early life stages and its effect on neurodevelopment. Lead exposure to the developing foetus targets foetal neural stem cells. Hence, it has detrimental effects on developing neural and glial cells, adversely influencing cognition and behaviour. Lead has a profound influence on the movement of calcium ions (Ca2+), which can be attributed to most of the mechanisms by which lead affects neurodevelopment. There is no known safe threshold of lead exposure for children. Lead can affect foetal neurodevelopment leading to various neurological disorders, and neurotoxic effects on behavioural and cognitive outcomes. In this review, we discuss prenatal and early-life lead exposure, its mechanism, and consequences for neurodegenerative disorders such as Alzheimer's disease and Parkinson's disease in later stages of life. This review further highlights the importance of lead exposure during pregnancy and lactation periods as well as early development of the child in understanding the extent of lead-induced neurological damage to the foetus/children and the associated future risks.

Lead exposure sources and public health investigations for children with elevated blood lead in England, 2014 to 2022.

Lead exposure at any concentration can adversely impact health, with children being more vulnerable to its effects. In England, children with an elevated blood lead concentration (BLC) are reported to Health Protection Teams (HPTs) for public health investigation. A detailed review of these cases has not yet been conducted. The objectives of this study were to describe the demographics, likely setting and sources of lead exposure, risk behaviours, public health investigations and outcomes for children aged <16 years with a BLC requiring public health action reported to HPTs between 2014-2022 in England. Data were collected via a lookback questionnaire and a live enhanced surveillance questionnaire. Data were deduplicated, cleaned and results summarised as numbers and percentages using R studio. A thematic analysis was conducted on qualitative responses to a question relating to problems experienced during case investigation. There were 340 cases in our study: the majority were aged 1-4 years old (53%) and male (69%). Ethnicity data was poorly recorded. A higher than expected proportion (31%) lived in the most deprived areas. Pica (76%) and learning difficulties (60%) were often present. Cases were primarily exposed to lead in the domestic setting (92%) with paint (43%) and soil (29%) the most common exposures. Most cases lived in rented accommodation (63%), with a higher proportion in social rentals (48%) than privately rented (37%). Case investigations were resource intensive and poor stakeholder engagement/response was most frequently identified as challenging by HPTs. Lead exposure is harmful to children and requires public health and clinical management, which can be complex and challenging. Prevention of lead exposure in children should be the focus of intervention efforts. Outreach, engagement and preventative work should focus on both renters and homeowners. Collecting ethnicity data consistently may enable identification of more specific groups at increased risk of lead exposure in England.

A Systematic Review and Meta-analysis of Chemical Exposures and Attention-Deficit/Hyperactivity Disorder in Children.

Exposure to certain chemicals prenatally and in childhood can impact development and may increase risk for attention-deficit/hyperactivity disorder (ADHD). Leveraging a larger set of literature searches conducted to synthesize results from longitudinal studies of potentially modifiable risk factors for childhood ADHD, we present meta-analytic results from 66 studies that examined the associations between early chemical exposures and later ADHD diagnosis or symptoms. Studies were eligible for inclusion if the chemical exposure occurred at least 6months prior to measurement of ADHD diagnosis or symptomatology. Included papers were published between 1975 and 2019 on exposure to anesthetics (n = 5), cadmium (n = 3), hexachlorobenzene (n = 4), lead (n = 22), mercury (n = 12), organophosphates (n = 7), and polychlorinated biphenyls (n = 13). Analyses are presented for each chemical exposure by type of ADHD outcome reported (categorical vs. continuous), type of ADHD measurement (overall measures of ADHD, ADHD symptoms only, ADHD diagnosis only, inattention only, hyperactivity/impulsivity only), and timing of exposure (prenatal vs. childhood vs. cumulative), whenever at least 3 relevant effect sizes were available. Childhood lead exposure was positively associated with ADHD diagnosis and symptoms in all analyses except for the prenatal analyses (odds ratios (ORs) ranging from 1.60 to 2.62, correlation coefficients (CCs) ranging from 0.14 to 0.16). Other statistically significant associations were limited to organophosphates (CC = 0.11, 95% confidence interval (CI): 0.03-0.19 for continuous measures of ADHD outcomes overall), polychlorinated biphenyls (CC = 0.08, 95% CI: 0.02-0.14 for continuous measures of inattention as the outcome), and both prenatal and childhood mercury exposure (CC = 0.02, 95% CI: 0.00-0.04 for continuous measures of ADHD outcomes overall for either exposure window). Our findings provide further support for negative impacts of prenatal and/or childhood exposure to certain chemicals and raise the possibility that primary prevention and targeted screening could prevent or mitigate ADHD symptomatology. Furthermore, these findings support the need for regular review of regulations as our scientific understanding of the risks posed by these chemicals evolves.

Matrix-matched calibrators are necessary for robust and high-quality dried blood spots lead screening assays by inductively coupled plasma-mass spectrometry

Background and aimsReliable lead screening methods are necessary to support early identification of lead exposure in children. Sample collection using dried blood spots (DBS) offers advantages compared to traditional venipuncture and capillary collection. Here, we describe and compare three lead DBS inductively coupled plasma-mass spectrometry (ICP-MS) methods for lead screening. Materials and methodsLead was extracted from Whatman 903 protein saver cards punches and analyzed by ICP-MS across three independent clinical laboratories. Each laboratory evaluated the performance of aqueous and matrix-matched DBS calibrators using external quality control samples (WI State of Laboratory of Hygiene Program). Leftover patient samples (n = 39) were used for an interlaboratory comparison of lead DBS. Lead DBS results were compared to whole blood methods. ResultsThe DBS ICP-MS methods using matrix-matched DBS calibrators had superior performance to the aqueous calibrations. There was a strong correlation between lead measured in DBS (matrix-matched) and whole blood for the three methods evaluated. ConclusionLead can be measured accurately by ICP-MS in DBS samples when matrix-matched calibrators are used. External quality control programs are valuable to assess the performance of DBS methods. DBS lead ICP-MS methods are a robust analytical option for lead screening even though the limitations of DBS are well recognized.

Making the case for lead safe housing: Downstream effects of lead exposure on outcomes for children and youth

Lead based paint is a predominate source of lead exposure in children, which has a documented negative effect on their health and development. Despite public health efforts, the housing stock in disinvested neighborhoods in many cities continues to present significant risk of childhood lead exposure. In this article, we describe how a multi-agency integrated data system was used to document the impact of lead exposure on indicators of child and youth development as recorded in educational and human service systems. By tracking administrative data for two cohorts of Cleveland, Ohio children from birth to early adulthood and using rigorous matching methods to reduce confounders when comparing those with and without elevated blood lead levels, we document negative effects on developmental, behavioral and socio-economic outcomes due to early childhood lead exposure. The magnitude of disparities between individuals who had elevated blood lead levels (≥5 μg/dL) in early childhood, compared to their matched counterparts, is in the ranges of 20–40%. The analysis is framed by clarifying the context, assumptions and limitations associated with the use of administrative data. This type of information has been useful in illuminating the burden of lead exposure for children, families and youth serving agencies and engaging public officials, landlords and residents in initiatives to bring housing up to lead safe standards.

Visual monitoring of lead exposure in children’s daily activities with an AuNP-based indicator

Lead exposure causes great harm to the growth and development of infants. A simple and fast approach that can be conveniently used at home is thus needed for parents to screen the potential lead sources in their children’s daily activities. Here, we developed a simple, fast, and sensitive gold nanoparticles (AuNPs)-based indicator for colorimetric Pb2+ detection. The method rationale was based on the higher affinity of Pb2+ to T30695 DNA over thioflavin T (ThT), as well as the stable and fast charge neutralization-induced assembly of AuNPs by ThT. To facilitate in-home monitoring, we arranged the reagents (AuNPs, DNA, ThT, and the buffer) and the required facilities (microplate and pipe) into a kit. Besides, the color change of the indicator AuNPs was monitored with a cell phone camera and processed with a self-developed APP. For samples closely related to children's daily activities, Pb2+ was successfully detected in saliva, sweat (simulated) and stomach fluid (simulated) extractions of water bottles, small benches, cushions, paint, lipstick, building blocks and toys. Therefore, continuous efforts are required for a lead-free life and such a kit can help the screening of lead-leaking clothing, food, shelter and toys for children.