Lead exposure in Chinese children: Urbanization lowers children's blood lead levels (BLLs)

Lead is a toxic metal that can pose a huge threat to children's health. China has experienced rapid urbanization since the reform in 1978; however, there has been no examination of the potential influence of this urbanization on children's blood lead levels (BLLs). This study is the initial investigation to explore the correlation between urbanization and BLLs in Chinese children. Five windows of time are considered: pre-2000, 2001-2005, 2006-2010, 2011-2015 and 2016-2021. The results show that urbanization affected lead distribution in urban soil and agricultural soil during the above periods, especially in northern China. The higher non-carcinogenic risk of lead for children is consistent with the lead pollution in soil (3 < Igeo ≤ 4). Urban children's BLLs are slightly higher than those of rural children in 2001-2010, but rural children's BLLs in 2011-2021 are higher than those of urban children during China's urbanization. The areas of rural decline and the areas of urban growth increased across all the window periods. However, the BLLs decrease in all rural and urban areas during all window periods, especially in urban areas. Children's BLLs have a significantly negative correlation with urban areas (p < 0.01). Therefore, China's urbanization has a significant effect on the decrease in children's BLLs. The significance of this study is to provide a fresh perspective and innovative strategy for policymaking in order to reduce children's BLLs and prevent lead exposure. This can be achieved by transforming their external living environment from a rural lifestyle to an urban one, while also ensuring access to well education and maintaining a balanced nutrient intake.

Rapid Market Screening to assess lead concentrations in consumer products across 25 low- and middle-income countries

Lead exposure can have serious consequences for health and development. The neurological and behavioral effects of lead are considered irreversible. Young children are particularly vulnerable to lead poisoning. In 2020, Pure Earth and UNICEF estimated that one in three children had elevated blood lead levels above 5 µg/dL. The sources of lead exposure vary around the world and can range from household products, such as spices or foodware, to environmental pollution from nearby industries. The aim of this study was to analyze common products from markets in low- and middle-income countries (LMICs) for their lead content to determine whether they are plausible sources of exposure. In 25 LMICs, the research teams systematically collected consumer products (metal foodware, ceramics, cosmetics, paints, toys, spices and other foods). The items were analyzed on site for detectable lead above 2 ppm using an X-ray fluorescence analyzer. For quality control purposes, a subset of the samples was analyzed in the USA using inductively coupled plasma mass spectrometry. The lead concentrations of the individual product types were compared with established regulatory thresholds. Out of 5007 analyzed products, threshold values (TV) were surpassed in 51% for metal foodware (TV 100 ppm), 45% for ceramics (TV 100 ppm), and 41% for paints (TV 90 ppm). Sources of exposure in LMICs can be diverse, and consumers in LMICs lack adequate protection from preventable sources of lead exposure. Rapid Market Screening is an innovative, simple, and useful tool to identify risky products that could be sources of lead exposure.

Effect of Environmental and Socioeconomic Factors on Increased Early Childhood Blood Lead Levels: A Case Study in Chicago

This study analyzes the prevalence of elevated blood lead levels (BLLs) in children across Chicagoland zip codes from 2019 to 2021, linking them to socioeconomic, environmental, and racial factors. Wilcoxon tests and generalized additive model (GAM) regressions identified economic hardship, reflected in per capita income and unemployment rates, as a significant contributor to increased lead poisoning (LP) rates. Additionally, LP rates correlate with the average age of buildings, particularly post the 1978 lead paint ban, illustrating policy impacts on health outcomes. The study further explores the novel area of land surface temperature (LST) effects on LP, finding that higher nighttime LST, indicative of urban heat island effects, correlates with increased LP. This finding gains additional significance in the context of anthropogenic climate change. When these factors are combined with the ongoing expansion of urban territories, a significant risk exists of escalating LP rates on a global scale. Racial disparity analysis revealed that Black and Hispanic/Latino populations face higher LP rates, primarily due to unemployment and older housing. The study underscores the necessity for targeted public health strategies to address these disparities, emphasizing the need for interventions that cater to the unique challenges of these at-risk communities.

Outbreak of lead poisoning from a civilian indoor firing range in the UK

INTRODUCTION

Lead exposure from discharged lead dust is a recognised risk at firing ranges. We report a lead poisoning outbreak among staff and their close contacts at a UK civilian indoor 24 m firing range.

METHODS

A retrospective review was undertaken of data collected on all patients at risk of lead poisoning identified either by direct referral to the Clinical Toxicology clinicians at the West Midlands Poisons Unit, or via the Trace Elements Supra-Regional Assay Service Laboratory at Sandwell hospital.

RESULTS

Eighty-seven patients were identified as having possible lead exposure, either at the firing range or via close contacts. Of these, 63 patients aged between 6 months and 78 years attended for blood lead concentration (BLC) testing. The highest BLC at presentation was 11.7 µmol/L (242 µg/dL). Only nine patients reported any symptoms at presentation. Fifteen patients received lead chelation therapy with oral dimercaptosuccinic acid (or succimer) 30 mg/kg/day or intravenous sodium calcium edetate (EDTA) 75 mg/kg/day, dependent on stock availability.

DISCUSSION

This report highlights the need for vigilance of lead poisoning as an occupational hazard in the UK, including at recreational facilities such as indoor firing ranges. It emphasises the importance of regulation of lead exposure in the workplace, particularly given the vague symptoms of lead poisoning, and proposes re-appraisal of UK legislation. This report also highlights potential issues surrounding stock availability of rarely used antidotes for uncommon presentations in the event of an outbreak of poisoning.

Secular trends in blood lead concentrations of school-age children in Montevideo, Uruguay from 2009 to 2019

Lead exposure continues to be a public health problem globally, yet very few countries perform systematic biomonitoring or surveillance of children's blood lead levels (BLLs). Secular trends in children's BLLs have not been well characterized outside North America and Europe. In 2009-19, we conducted a series of non-representative cross-sectional surveys in Montevideo, Uruguay, enrolling children living in areas of the city with known or suspected lead contamination. Lead was measured with atomic absorption spectrometry on fasting venous blood samples. Of the 856 children representing independent (non-sibling) observations, 759 had BLL measures. Other missing data were imputed. Using linear and logistic regression models, we estimated the covariate-adjusted year to year difference in mean BLL and the likelihood of having BLL ≥5 and BLL ≥3.5 μg/dL. At the start of the study, mean ± SD BLL was 4.8 ± 2.6 μg/dL, and at the end 1.4 ± 1.4 μg/dL. The prevalence of BLL ≥5 and BLL ≥3.5 μg/dL also differed markedly between 2009 and 2019 (30.8% vs. 2.7% and 53.8% vs. 5.8%). Similarly, where 80.8% of children had BLL ≥2 μg/dL in 2011, in 2019 that number was 19.3%. The estimated year to year difference in BLL was ∼0.3 μg/dL. Despite this progress, pediatric lead exposure remains a problem in Montevideo. In years 2015-19, between 19 and 48% of school children had BLL ≥2 μg/dL, a level at which adverse neurobehavioral outcomes continue to be reported in the literature. Continued prevention and risk-reduction efforts are needed in Montevideo, including systematic surveillance of BLLs in all children.

Who tests for lead and why? A 10-year analysis of blood lead screening, follow-up and CNS outcomes in a statewide US healthcare system

OBJECTIVES

This study aims to determine (1) which providers in US healthcare systems order lead tests, why and at what frequency and (2) whether current patient population lead levels are predictive of clinical outcomes.

METHODS

Retrospective medical record study of all blood lead tests in the Medical University of South Carolina healthcare system 2012-2016 and consequent evidence of central nervous system (CNS)-related disease across a potential 10-year window (2012-2022).

RESULTS

Across 4 years, 9726 lead tests resulted for 7181 patients (49.0% female; 0-94 years), representing 0.2% of the hospital population. Most tests were for young (76.6%≤age 3) and non-Hispanic black (47.2%) and Hispanic (26.7%) patients. A wide variety of providers ordered tests; however, most were ordered by paediatrics, psychiatry, internal medicine and neurology. Lead levels ranged from ≤2.0 µg/dL (80.8%) to ≥10 µg/dL (0.8%; max 36 µg/dL). 201 children (3.1%) had initial lead levels over the reference value for case management at the time (5.0 µg/dL). Many high level children did not receive follow-up testing in the system (36.3%) and those that did often failed to see levels fall below 5.0 µg/dL (80.1%). Non-Hispanic black and Hispanic patients were more likely to see lead levels stay high or go up over time. Over follow-up, children with high lead levels were more likely to receive new attention-deficit/hyperactivity disorder and conduct disorder diagnoses and new psychiatric medications. No significant associations were found between lead test results and new CNS diagnoses or medications among adults.

CONCLUSIONS

Hospital lead testing covers a small portion of patients but includes a wide range of ages, presentations and provider specialities. Lack of lead decline among many paediatric patients suggests there is room to improve provider guidance around when to test and follow-up.

Clinical case analysis of 32 children aged 0-6 years with lead poisoning in Nanning, China

Lead is one of the heavy metals that is toxic and widely distributed in the environment, and children are more sensitive to the toxic effects of lead because the blood-brain barrier and immune system are not yet well developed. The objective of the study was to investigate the clinical characteristics of lead poisoning in children aged 0∼6 years in a hospital in Guangxi, and to provide scientific basis for the prevention and treatment of lead poisoning. We collected and analyzed the clinical data of 32 children with lead poisoning admitted to a hospital in Guangxi from 2010 to 2018. The results showed that most of the 32 cases presented with hyperactivity, irritability, poor appetite, abdominal pain, diarrhea, or constipation. The hemoglobin (HGB), mean corpusular volume (MCV), mean corpuscular hemoglobin (MCH), and hematocrit (HCT) of the lead-poisoned children were all decreased to different degrees and were below normal acceptable levels. Urinary β2-microglobulin was increased. Blood lead levels (BLL) decreased significantly after intravenous injection of the lead chelator, calcium disodium edetate (CaNa2-EDTA). In addition, HGB returned to normal levels, while MCV, MCH, and HCT increased but remained below normal levels. Urinary β2-microglobulin was reduced to normal levels. Therefore, in this cohort of children, the high-risk factors for lead poisoning are mainly Chinese medicines, such as baby powder. In conclusion, lead poisoning caused neurological damage and behavioral changes in children and decreased erythrocyte parameters, leading to digestive symptoms and renal impairment, which can be attenuated by CaNa2-EDTA treatment.

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.

Gastrointestinal Manifestations of Lead Poisoning: A Brief Report

Gastrointestinal (GI) manifestations of lead poisoning include abdominal pain, constipation, and diarrhea. Depending on the severity of a symptom, surgical consultation is required. The present study aimed to make a comparison between the mean blood lead levels of patients hospitalized for lead toxicity and the various Gl symptoms. A retrospective cross-sectional study was performed in 2020 at Khorshid Hospital, the main regional referral center for poisoned patients (Isfahan, Iran). A total of 82 patients aged ≥18 years who were hospitalized for lead poisoning during 2017-2018 were included in the study. Patients' information was extracted from hospital medical records, including demographic information, clinical manifestations, blood lead levels, and treatment outcome. The mean age of the patients was 48.18±11.9 years, 91.5% were men, and 62.2% suffered from multiple GI symptoms, with abdominal pain being predominant (31.7%). Blood lead levels in patients with multiple GI symptoms were higher than those with only one symptom (P=0.01). Surgical consultation was required in 14.6% of the patients. Multiple GI symptoms were the main predictive factor for blood lead levels above 70 mg/dL (P=0.03, Odds ratio=3.06, 95% CI=1.09-8.61). Given the prevalence of abdominal pain and its association with elevated blood lead levels, differential diagnosis of abdominal pain should include lead toxicity.

High blood lead levels of children in a gold mining community in Osun State, Nigeria: an urgent call for action

BACKGROUND

Environmental exposure from artisanal gold mining activities is a major risk for high blood lead levels (BLLs) in children. Over the last decade, artisanal gold mining activities have been on a sharp increase in some parts of Nigeria. This study compared BLLs of children in the mining community of Itagunmodi and a 50-km distant non-mining community of Imesi-Ile, Osun State, Nigeria.

METHODS

This community-based study investigated 234 apparently healthy children, with 117 each from Itagunmodi and Imesi-Ile. Relevant history, examination and laboratory findings including BLLs were recorded and analysed.

RESULTS

All participants had BLLs above the cut-off value of 5 µg/dl. However, the mean BLL of subjects living in the gold-mining community (24.2±5.3 µg/dl) was significantly higher than for children in the non-mining area of Imesi-Ile (19.5±6.4 µg/dl; p<0.001). Children in the gold mining community were 3.07 times more likely to have a BLL ≥20 µg/dl than those in the non-mining environment (odds ratio [OR] 3.07 [95% confidence interval {CI} 1.79 to 5.2], p<0.001). Similarly, the odds of having a BLL ≥30 µg/dl was 7.84 times more likely among children living in gold mining Itagunmodi than in Imesi-Ile (OR 7.84 [95% CI 2.32 to 26.46], p<0.0001). BLL was not associated with socio-economic and nutritional status of the participants.

CONCLUSIONS

In addition to introduction and enforcement of safe mining practices, regular screening for lead toxicity is advocated for children in these communities.

Using Artificial Intelligence to Identify Sources and Pathways of Lead Exposure in Children

CONTEXT

Sources and pathways of lead exposure in young children have not been analyzed using new artificial intelligence methods.

OBJECTIVE

To collect environmental, behavioral, and other data on sources and pathways in 17 rural homes to predict at-risk households and to compare urban and rural indicators of exposure.

DESIGN

Cross-sectional pilot study.

SETTING

Knox County, Illinois, which has a high rate of childhood lead poisoning.

PARTICIPANTS

Rural families.

METHODS

Neural network and K-means statistical analysis.

MAIN OUTCOME MEASURE

Children's blood lead level.

RESULTS

Lead paint on doors, lead dust, residential property assessed tax, and median interior paint lead level were the most important predictors of children's blood lead level.

CONCLUSIONS

K-means analysis confirmed that settled house dust lead loadings, age of housing, concentration of lead in door paint, and geometric mean of interior lead paint samples were the most important predictors of lead in children's blood. However, assessed property tax also emerged as a new predictor. A sampling strategy that examines these variables can provide lead poisoning prevention professionals with an efficient and cost-effective means of identifying priority homes for lead remediation. The ability to preemptively target remediation efforts can help health, housing, and other agencies to remove lead hazards before children develop irreversible health effects and incur costs associated with lead in their blood.

Neurotoxicity and Outcomes from Developmental Lead Exposure: Persistent or Permanent?

BACKGROUND

Childhood lead poisoning remains an important public health issue in the United States, as well as elsewhere in the world. Although primary prevention is a major goal and it is critically important to keep children from getting poisoned, it is also important to explore ways to reduce the neurotoxic effects of lead in those children already poisoned. Whether lead-induced neurotoxicity and its related adverse outcomes are viewed as "permanent" or "persistent" may influence the way in which potential remediation efforts are considered for improving outcomes from childhood lead poisoning.

OBJECTIVES

The objective of this commentary was to discuss the ideas of permanence and persistence in relation to the direct neurotoxic effects of lead on the brain and the resulting adverse outcomes from these effects. Recent new insights regarding potential mitigation of lead-induced neurotoxic effects on brain and behavior are considered along with clinical information on neurorehabilitation to suggest potential strategies for improving cognitive/behavioral outcomes in lead-poisoned children.

DISCUSSION

The distinction between permanent and persistent in regard to lead-induced neurotoxicity and its resulting outcomes may have broad implications for public health policies in response to the problem of childhood lead exposure. The term permanent implies that the damage is irreversible with little chance of improvement. However, there is evidence that at least some of the adverse cognitive/behavioral outcomes from lead exposure are persistent rather than permanent and potentially amenable, under the appropriate circumstances, to some level of mitigation. This author recommends that clinical, interventional research efforts be devoted to exploring optimal neurorehabilitative and enrichment conditions to stimulate plasticity and enhance functioning to determine the extent to which promising results from preclinical studies of lead-induced brain damage and the mitigation of these effects can be successfully translated to humans. https://doi.org/10.1289/EHP12371.

Using blood lead concentrations of wildlife sentinels to identify environmental risk factors of lead exposure for public health and wildlife rehabilitation efforts

Lead poisoning remains a persistent health issue for both humans and wildlife, despite strides to reduce lead contamination in the environment. Using Geographic Information Systems (GIS), this study explores the associations between blood lead levels (BLLs) in wildlife sentinels and possible built environment lead exposure risk factors in the Minneapolis-Saint Paul, Minnesota urban area. Results show a high-level of heterogeneity in animal BLLs (n = 472) across our urban environment and suggest that each kilometer increase in road density is associated with a 17.07% (95% CI: 1.48%, 35.05%) increase in BLL in our study species of Virginia opossums and Eastern gray squirrels, and a 14.28% (95% CI: 1.16%, 29.09%) increase in BLL of rock pigeons. For squirrels and opossums, we see an additional 5.72% (95% CI: 0.59%, 10.85%) increased risk of BLL for every 1000 people per square-mile. The relationship between animal sentinels and environmental hazards can give us an insight into the potential lead exposure risks for humans. The use of wildlife sentinel data to explore environmental risk factors supports a One Health approach to better address public health questions and aid in wildlife rehabilitation related to residual lead poisoning from ambient environmental exposures.

Predicting Low-Level Childhood Lead Exposure in Metro Atlanta Using Ensemble Machine Learning of High-Resolution Raster Cells

Low-level lead exposure in children is a major public health issue. Higher-resolution spatial targeting would significantly improve county and state-wide policies and programs for lead exposure prevention that generally intervene across large geographic areas. We use stack-ensemble machine learning, including an elastic net generalized linear model, gradient-boosted machine, and deep neural network, to predict the number of children with venous blood lead levels (BLLs) ≥2 to <5 µg/dL and ≥5 µg/dL in ~1 km2 raster cells in the metro Atlanta region using a sample of 92,792 children ≤5 years old screened between 2010 and 2018. Permutation-based predictor importance and partial dependence plots were used for interpretation. Maps of predicted vs. observed values were generated to compare model performance. According to the EPA Toxic Release Inventory for air-based toxic release facility density, the percentage of the population below the poverty threshold, crime, and road network density was positively associated with the number of children with low-level lead exposure, whereas the percentage of the white population was inversely associated. While predictions generally matched observed values, cells with high counts of lead exposure were underestimated. High-resolution geographic prediction of lead-exposed children using ensemble machine learning is a promising approach to enhance lead prevention efforts.

Improving Equitability and Inclusion for Testing and Detection of Lead Poisoning in US Children

Policy Points Child lead poisoning is associated with socioeconomic inequity and perpetuates health inequality. Methods for testing and detection of child lead poisoning are ill suited to the current demographics and characteristics of the problem. A three-pronged revision of current testing approaches is suggested. Employing the suggested revisions can immediately increase our national capacity for equitable, inclusive testing and detection. ABSTRACT: Child lead poisoning, the longest-standing child public health epidemic in US history, is associated with socioeconomic inequity and perpetuates health inequality. Removing lead from children's environments ("primary prevention") is and must remain the definitive solution for ending child lead poisoning. Until that goal can be realized, protecting children's health necessarily depends on the adequacy of our methods for testing and detection. Current methods for testing and detection, however, are no longer suited to the demographics and magnitude of the problem. We discuss the potential deployment and feasibility of a three-pronged revision of current practices including: 1) acceptance of capillary samples for final determination of lead poisoning, with electronic documentation of "clean" collection methods submitted by workers who complete simple Centers for Disease Control and Prevention-endorsed online training and certification for capillary sample collection; 2) new guidance specifying the analysis of capillary samples by inductively coupled plasma mass spectrometry or graphite furnace atomic absorption spectrometry with documented limit of detection ≤0.2 μg/dL; and 3) adaptive "census tract-specific" universal testing and monitoring guidance for children from birth to 10 years of age. These testing modifications can bring child blood lead level (BLL) testing into homes and communities, immediately increasing our national capacity for inclusive and equitable detection and monitoring of dangerous lower-range BLLs in US children.

Childhood Lead Poisoning 1970-2022: Charting Progress and Needed Reforms

CONTEXT

Childhood lead poisoning prevention in the United States was marked by a largely failed medical approach from 1971 to 1990; an emergent (but small) healthy housing primary prevention strategy from 1991 to 2015; and implementation of large-scale proven interventions since then.

PROGRAM

Childhood Lead Poisoning Prevention & Healthy Housing.

METHODS

Historic and recent health and housing data from the National Health and Nutrition Examination Survey (NHANES) and the American Healthy Homes Survey (AHHS) were retrieved to analyze trends and associated policy gaps.

EVALUATION

Approximately 590 000 US children aged 1 through 5 years had elevated blood lead levels of 3.5 μg/dL and greater in 2016, and 4.3 million children resided in homes with lead paint in 2019. Despite large improvements, racial and other disparities remain stubbornly and statistically significant. The NHANES and the AHHS require larger sample sizes. The Centers for Disease Control and Prevention has not published children's blood lead surveillance and NHANES data in several years; the Department of Housing and Urban Development (HUD) has no analogous housing surveillance system; and the Environmental Protection Agency (EPA) and the Occupational Safety and Health Administration (OSHA) have not updated training, Superfund, and occupational standards in decades.

DISCUSSION

The nation has been without a plan and an associated budget for more than 2 decades. Congress has not reformed the nation's main lead poisoning prevention laws in more than 30 years. Such reforms include stopping US companies from producing new residential lead paint in other countries; enabling the disclosure law to identify all residential lead hazards; closing loopholes in federally assisted housing regulations and mortgage insurance standards; harnessing tax policy to help homeowners mitigate lead hazards; streamlining training requirements; increasing the size of health and housing surveys and surveillance systems; and updating housing codes, medical guidance, dust lead standards, training, Superfund, and worker exposure limits. Congress and the president should reauthorize a cabinet-level task force (dormant since 2010) to develop a new strategic plan with an interagency budget to implement it. These reforms will scale and optimize markets, subsidies, enforcement, and other proven interventions to end ineffective, costly, harmful, and irrational cost shifting that threatens children, workers, and affordable housing.

Individual and Neighborhood Characteristics Associated With Confirmatory and Follow-up Blood Lead Testing Among Children With Elevated Blood Lead Levels

OBJECTIVES

The aim of this study was to assess the proportions and likelihood of children who receive confirmatory and follow-up blood lead testing within the recommended time frames after an initial capillary elevated blood lead level (EBLL) and confirmed EBLL, respectively, by individual and neighborhood-level sociodemographic characteristics.

DESIGN

We linked and used blood testing and sociodemographic characteristics data from a Pennsylvania birth cohort including children born between 2017 and 2018. Generalized linear mixed models were constructed to examine the associations between sociodemographic factors and having recommended confirmatory and follow-up testing.

SETTING

A population-based, retrospective cohort study.

PARTICIPANTS

In this birth cohort, children who underwent at least 1 BLL test were followed up to 24 months of age. Children with a first unconfirmed (n = 6259) and confirmed BLL (n = 4213) ≥ 5 μg/dL were included in the analysis.

MAIN OUTCOME MEASURE

Children had confirmatory and follow-up testing within the recommended time frames.

RESULTS

Of the children with unconfirmed and confirmed EBLLs, 3555 (56.8%) and 1298 (30.8%) received confirmatory and follow-up testing, respectively. The proportions of the 2 outcome measures were lower among children experiencing certain sociodemographic disadvantages. In the univariate analyses, lower initial BLLs, older age, non-Hispanic Blacks, lower maternal educational levels, maternal Medicaid, The Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) enrollment, maternal smoking, and higher quartiles of neighborhood poverty and old housing were associated with lower odds of having confirmatory and follow-up testing. However, in multivariate models, children with lower initial BLLs, older age, maternal smoking, and non-Hispanic Blacks were significantly less likely to have confirmatory and follow-up testing.

CONCLUSIONS

There were deficiencies in having recommended confirmatory and follow-up blood lead testing among children, especially those with sociodemographic disadvantages. Public health agencies and stakeholders should finetune policies to improve follow-up testing in conjunction with primary and secondary preventions for early detection and reduction of lead exposure among targeted children at risk of lead poisoning.

Using exterior housing conditions to predict elevated pediatric blood lead levels

Housing-based lead paint dust is the most common source of lead exposure for US-born children. Although year of housing construction is a critical indicator of the lead hazard to US children, not all housing of the same age poses the same risk to children. Additional information about housing condition is required to differentiate the housing-based lead risk at the parcel level. This study aimed to identify and assess a method for gathering and using observations of exterior housing conditions to identify active housing-based lead hazards at the parcel level. We used a dataset of pediatric blood lead observations (sample years 2000-2013, ages 6-72 months, n = 6,589) to assess associations between observations of exterior housing conditions and housing-based lead risk. We used graphical and Lasso regression methods to estimate the likelihood of an elevated blood lead observation (≥3.5 μg/dL). Our methods estimate a monotonic increase in the likelihood of an elevated blood lead observation as housing conditions deteriorate with the largest changes associated with homes in the greatest disrepair. Additionally we estimate that age of home construction works in consort with housing conditions to amplify risks among those houses built before 1952. Our analysis indicates that a survey of external housing conditions can be used in combination with age of housing in the identification process, at the parcel level, of homes that pose a housing-based lead hazard to children.

Lead Levels in Spices From Market Basket and Home Lead Investigation Samples in North Carolina

OBJECTIVES

Lead investigators in North Carolina found evidence that contaminated spices may contribute to children's elevated blood lead levels. We compared lead levels in samples of spices and other consumable products by country of purchase to inform consumer safety interventions and regulations.

METHODS

From February 1, 2011, through October 22, 2020, North Carolina lead investigators sampled spices and other consumable products from 103 homes of children with confirmed elevated blood lead levels. In 2017, the study team purchased 50 products frequently sampled during lead investigations, as a "market basket" sample, from local stores in or near Raleigh, North Carolina. The State Laboratory of Public Health analyzed 423 product samples using mass spectrometry. We extracted environmental sample results from lead investigations from the North Carolina Electronic Lead Surveillance System.

RESULTS

The median market basket lead result was 0.07 mg/kg (SD = 0.17); the maximum lead result was 0.88 mg/kg. The median home lead investigation sample result was 0.26 mg/kg (SD = 489.44); the maximum lead result was 6504.00 mg/kg in turmeric purchased in India. Among all samples, products purchased in India had more than triple the median lead levels (0.71 mg/kg) of those purchased in the United States (0.19 mg/kg).

CONCLUSIONS

Purchasing spices in the United States is an action that consumers can take that may reduce their lead poisoning risk. Regulatory agencies should consider a lead limit of <1 mg/kg as attainable for spices sold in US stores and for ingredients of any foods that may be consumed by children.

Blood lead levels in 2018/2019 compared to 1987/1988 in the German population-based KORA study

INTRODUCTION

Lead exposure remains of continuing concern due to its known and suspected impacts on human health and has been designated as a priority substance for investigation in human biomonitoring studies by the EU. The aims of this study were to measure blood lead levels (BLL) in a population based cohort of middle-aged individuals without major current exposures to lead, and to compare these to historical blood lead levels obtained thirty years earlier.

METHODS

The population-based KORA study from 1984 to 2001 included inhabitants of the Augsburg Region, Germany. During 2018 to 2019, a subsample of these participants (KORA-Fit) was invited for interview regarding demographic and lifestyle factors, physical examination and blood withdrawal. Blood samples were stored at -80C prior to measurement of BLL via graphite furnace atomic absorption spectroscopy (GF-AAS). Descriptive and multivariable analyses were performed.

RESULTS

BLLs were measured in 3033 eligible persons aged 54 to 73, establishing a geometric mean (GM) BLL of 24.8 μg/l in 2018/19. Of these, 555 (18%) had BLL above proposed 95th percentile reference values of the German Environment Agency. Only small differences were found in BLL stratified by sociodemographic categories, however regular smokers had higher GM BLL (26.1 μg/l) compared to never smokers (23.7 μg/l), and an increasing BLL with increased wine consumption was noted. For 556 individuals, BLLs (GM: 54.0 μg/l) reduced by 35% in men and 50% in women compared to levels in 1987/88 with only 1.4% of individuals having an unchanged or increased BLL.

DISCUSSION

KORA-Fit provided contemporary normative data for BLL in a Western European population without major current sources of lead exposure. Mean BLLs have fallen since the 1980s using historical BLL data which is likely linked to the ban of leaded gasoline. Nevertheless, BLLs in this population remain elevated at levels associated with morbidity and mortality.

Narrative review of lead poisoning in humans caused by industrial activities and measures compatible with sustainable industrial activities in Republic of Zambia

Lead (Pb) pollution and human exposure to Pb, is an important issue for the international community to address being associated with 0.90 million deaths from long-term effects. The Republic of Zambia is a typical mineral resource-rich country, with long-standing mining and smelting activities of metals including Pb in several parts of the country. This narrative review provides a comprehensive overview of previous papers that have assessed human exposure to Pb and related health effects in Zambia. Environmental remediation methods that should be applied locally, ways to reduce Pb exposure of the population, and issues that need to be addressed by various sectors are discussed. Environmental remediation methods using locally available and affordable materials are needed to ensure both sustainable industrial activities and pollution prevention. In the Zambian mining towns, including Kabwe, various research activities have been conducted, including environmental monitoring, human biomonitoring and health impact assessments. The town of Kabwe, which was one of Zambia's largest Pb mining area in the 20th century, continues to have formal and informal Pb-related industries and is known as one of the most polluted areas in the world. For example, despite the World Health Organization asserting that "For an individual with a blood Pb concentration ≥ 5 μg/dL, appropriate action should be taken to terminate exposure", there are reports of blood Pb levels in Kabwe children exceeding 100 μg/dL. While Pb pollution is a global issue, not many places have such continuous and comprehensive research has been conducted, and there is much to be learned from the knowledge accumulated in these areas. Because the high levels of Pb accumulation in humans and the adverse health effects were clarified, we consider that it is important to combine mining activities, which are a key industry, with measures to prevent environmental pollution.

Exposure Sources Among Veterans With Elevated Blood Lead Levels, United States, 2015‒2021

Objectives. To determine characteristics and sources of exposure in veterans with elevated blood lead levels (BLLs). Methods. We included users of US Veterans Health Administration care aged 18 years or older tested for BLL from October 2015 to September 2021. Prevalence of BLL 10 micrograms per deciliter (µg/dL) or higher and 25 µg/dL or higher was determined within demographic groups. Logistic regression analysis measured association of International Classification of Diseases, Tenth Revision, Clinical Modification‒coded conditions with elevated BLL. Electronic notes were reviewed for exposure sources. Results. Among 1007 unique veterans with BLL 10 µg/dL or higher, prevalence of BLL 10 µg/dL or higher and 25 µg/dL or higher peaked at 4.9 and 1.3 per 100 000 veterans, respectively (fiscal year 2019), and was highest in non-Hispanic White men and those aged 25 to 34 years. Conditions predicted by elevated BLL were attention-deficit/hyperactivity disorder (ADHD) and nausea or vomiting. Firearms represented 70.1% of occupational and 85.9% of nonoccupational exposures. Toxicology consults occurred in 17 of 298 (6%) with BLL 25 µg/dL or higher. Conclusions. Firearms were the largest exposure source among veterans with elevated BLL. Clinicians should be alert for potential conditions (including ADHD and nausea or vomiting in our study) associated with lead exposure. Standardization of care regarding toxicology referral practices is warranted. (Am J Public Health. 2022;112(S7):S670-S678. https://doi.org/10.2105/AJPH.2022.306936).

Detecting New Sources of Childhood Environmental Lead Exposure Using a Statistical Surveillance System, 2015-2019

Objectives. To design and implement a statistical surveillance system to prospectively identify potential clusters of elevated blood lead levels (EBLLs) in children younger than 6 years in the Denver, Colorado, metro area. Methods. We evaluated the ability of 2 independent statistical surveillance methods to detect synthetic clusters of EBLLs in Denver between 2015 and 2019. Results. Together, the statistical surveillance methods took an average of 9 months to detect the synthetic clusters. This is faster than similar real-world clusters that have been reported in the past. The system was relatively unaffected by changes in the testing rate and to the blood lead reference value. Conclusions. The adequate design of a statistical surveillance system can help increase the rate at which clusters of EBLLs are detected in Denver, but doing so requires an accurate model of the spatial distribution of EBLLs. Earlier detection of clusters can help guide more effective public health interventions at the local level. (Am J Public Health. 2022;112(S7):S715-S722. https://doi.org/10.2105/AJPH.2022.307009).

Industries With the Highest Occupational Blood Lead Test Results, California Occupational Blood Lead Registry, 2020‒2021

Objectives. To evaluate the focused surveillance of blood lead results of 20 micrograms per deciliter (µg/dL) of venous blood and higher received by the California Occupational Blood Lead Registry (Registry) because of new legislation concerning occupational lead poisoning. Methods. We used occupational blood lead results reported to the Registry from January 1, 2020, to December 31, 2021, to describe the current industries with workers having the highest levels of lead poisoning. Results. The Registry received 239 blood lead levels (BLLs) of 20 µg/dL or higher for 151 adults with occupational lead exposure in 28 industries over the study period. Worker BLLs ranged from 20 µg/dL to 55 µg/dL. The industries with the greatest number of workers were storage battery manufacturing, painting contractors, and shooting ranges. Conclusions. Occupational lead poisoning is a health concern across numerous industries in California. The current outdated state and federal occupational lead standards would not require removal from lead work for any of the workers in this study despite extensive evidence of harm at lower BLLs. Strengthened standards could support public health initiatives for worker protection and reduce take-home lead to family members. (Am J Public Health. 2022;112(S7):S690-S694. https://doi.org/10.2105/AJPH.2022.307002).

Health Remedies as a Source of Lead, Mercury, and Arsenic Exposure, New York City, 2010-2019

Objectives. To describe the types of health remedies collected during poisoning investigations in New York City over a 10-year period that were found to contain high levels of lead, mercury, or arsenic. Methods. Between 2010 and 2019, the New York City Department of Health and Mental Hygiene collected 584 samples of health remedies during poisoning investigations and store surveys for lead, mercury, or arsenic analysis. Results. There was a significant association between blood lead levels and estimated cumulative daily lead exposures among adult users of rasa shastra Ayurvedic medications. Also, average blood lead levels among adult rasa shastra users were significantly higher than levels among those using other types of non-Ayurvedic health remedies. Conclusions. Rasa shastra Ayurvedic medications can contain very high levels of lead, mercury, and arsenic. This underscores the importance of screening for lead, mercury, and arsenic exposures within at-risk populations. Public Health Implications. The general ease of accessibility to rasa shastra medications raises concerns. There is a need for systemic change that results in primary prevention, that is, removal of the source through policy development and regulatory enforcement in the country of origin. (Am J Public Health. 2022;112(S7):S730-S740. https://doi.org/10.2105/AJPH.2022.306906).

Blood Lead Level Testing and Retesting Among Newly Arriving Refugee Children, Pennsylvania, 2015-2019

Objectives. To (1) determine the prevalence of elevated blood lead levels (EBLLs; ≥ 5 µg/dL) among newly arrived refugee children, (2) understand the demographic characteristics of refugee children with EBLLs, and (3) assess health care providers' compliance with Centers for Disease Control and Prevention (CDC) recommendations for retesting. Methods. We matched refugee demographic data (2015-2019) from the CDC's Electronic Disease Notification (EDN) system with lead-testing laboratory report data from the Pennsylvania National Electronic Disease Surveillance System using Match*Pro software. Results. Of 3833 refugee children 16 years or younger in the EDN system, matching identified 3142 children with blood lead level data. Among children with blood lead level data, 578 (18.4%) had EBLLs. Among children with EBLLs, 341 (59.0%) were male. Of the 1370 children aged 6 years or younger with blood level test results, 335 (24.5%) had initial EBLLs, and only 78 (5.7%) were retested within 3 to 6 months. Of the 335 children 6 years or younger with an initial EBLL, only 44 (13.1%) were retested within 3 to 6 months. Conclusions. Following up on refugee children with EBLLs is necessary to ensure that they do not have continued lead exposure. (Am J Public Health. 2022;112(S7):S706-S714. https://doi.org/10.2105/AJPH.2022.306856).

Method to assess the potential magnitude of terrestrial European avian population reductions from ingestion of lead ammunition

Current estimates of terrestrial bird losses across Europe from ingestion of lead ammunition are based on uncertain or generic assumptions. A method is needed to develop defensible European-specific estimates compatible with available data that does not require long-term field studies. We propose a 2-step method using carcass data and population models. The method estimates percentage of deaths diagnosed as directly caused by lead poisoning as a lower bound and, as an upper bound, the percentage of possible deaths from sublethal lead poisoning that weakens birds, making them susceptible to death by other causes. We use these estimates to modify known population-level annual mortality. Our method also allows for potential reductions in reproduction from lead shot ingestion because reductions in survival and reproduction are entered into population models of species with life histories representative of the most groups of susceptible species. The models estimate the sustainability and potential population decreases from lead poisoning in Europe. Using the best available data, we demonstrate the method on two taxonomic groups of birds: gallinaceous birds and diurnal raptors. The direction of the population trends affects the estimate, and we incorporated such trends into the method. Our midpoint estimates of the reduction in population size of the European gallinaceous bird (< 2%) group and raptor group (2.9–7.7%) depend on the species life history, maximum growth rate, population trend, and if reproduction is assumed to be reduced. Our estimates can be refined as more information becomes available in countries with data gaps. We advocate use of this method to improve upon or supplement approaches currently being used. As we demonstrate, the method also can be applied to individual species of concern if enough data across countries are available.

A Generalizable Evaluated Approach, Applying Advanced Geospatial Statistical Methods, to Identify High Lead Exposure Locations at Census Tract Scale: Michigan Case Study

BACKGROUND

Despite great progress in reducing environmental lead (Pb) levels, many children in the United States are still being exposed.

OBJECTIVE

Our aim was to develop a generalizable approach for systematically identifying, verifying, and analyzing locations with high prevalence of children's elevated blood Pb levels (EBLLs) and to assess available Pb models/indices as surrogates, using a Michigan case study.

METHODS

We obtained ∼1.9 million BLL test results of children <6 years of age in Michigan from 2006-2016; we then evaluated them for data representativeness by comparing two percentage EBLL (%EBLL) rates (number of children tested with EBLL divided by both number of children tested and total population). We analyzed %EBLLs across census tracts over three time periods and between two EBLL reference values (≥5 vs. ≥10μg/dL) to evaluate consistency. Locations with high %EBLLs were identified by a top 20 percentile method and a Getis-Ord Gi* geospatial cluster "hotspot" analysis. For the locations identified, we analyzed convergences with three available Pb exposure models/indices based on old housing and sociodemographics.

RESULTS

Analyses of 2014-2016 %EBLL data identified 11 Michigan locations via cluster analysis and 80 additional locations via the top 20 percentile method and their associated census tracts. Data representativeness and consistency were supported by a 0.93 correlation coefficient between the two EBLL rates over 11 y, and a Kappa score of ∼0.8 of %EBLL hotspots across the time periods (2014-2016) and reference values. Many EBLL hotspot locations converge with current Pb exposure models/indices; others diverge, suggesting additional Pb sources for targeted interventions.

DISCUSSION

This analysis confirmed known Pb hotspot locations and revealed new ones at a finer geographic resolution than previously available, using advanced geospatial statistical methods and mapping/visualization. It also assessed the utility of surrogates in the absence of blood Pb data. This approach could be applied to other states to inform Pb mitigation and prevention efforts. https://doi.org/10.1289/EHP9705.

Patterns of Children's Blood Lead Screening and Blood Lead Levels in North Carolina, 2011-2018-Who Is Tested, Who Is Missed?

BACKGROUND

No safe level of lead in blood has been identified. Blood lead testing is required for children on Medicaid, but it is at the discretion of providers and parents for others. Elevated blood lead levels (EBLLs) cannot be identified in children who are not tested.

OBJECTIVES

The aims of this research were to identify determinants of lead testing and EBLLs among North Carolina children and estimate the number of additional children with EBLLs among those not tested.

METHODS

We linked geocoded North Carolina birth certificates from 2011-2016 to 2010 U.S. Census data and North Carolina blood lead test results from 2011-2018. We estimated the probability of being screened for lead and created inverse probability (IP) of testing weights. We evaluated the risk of an EBLL of ≥3μg/dL at <30  months of age, conditional on characteristics at birth, using generalized linear models and then applied IP weights to account for missing blood lead results among unscreened children. We estimated the number of additional children with EBLLs of all North Carolina children using the IP-weighted population and bootstrapping to produce 95% credible intervals (CrI).

RESULTS

Mothers of the 63.5% of children (402,002 of 633,159) linked to a blood lead test result were disproportionately young, Hispanic, Black, American Indian, or on Medicaid. In full models, maternal age ≤20y [risk ratio (RR)=1.10; 95% confidence interval (CI): 1.13, 1.20] or smoking (RR=1.14; 95% CI: 1.12, 1.17); proximity to a major roadway (RR=1.10; 95% CI: 1.05, 1.15); proximity to a lead-releasing Toxics Release Inventory site (RR=1.08; 95% CI: 1.03, 1.14) or a National Emissions Inventory site (RR=1.11; 95% CI: 1.07, 1.14); and living in neighborhoods with more housing built before 1950 (RR=1.10; 95% CI: 1.05, 1.14) or before 1940 (RR=1.18; 95% CI: 1.11, 1.25) or more vacant housing (RR=1.14; 95% CI: 1.11, 1.17) were associated with an increased risk of EBLL, whereas overlap with a public water service system was associated with a decreased risk of EBLL (RR=0.85; 95% CI: 0.83, 0.87). Children of Black mothers were no more likely than children of White mothers to have EBLLs (RR=0.98; 95% CI: 0.96, 1.01). Complete blood lead screening in 2011-2018 may have identified an additional 17,543 (95% CrI: 17,462, 17,650) children with EBLLs ≥3μg/dL.

DISCUSSION

Our results indicate that current North Carolina lead screening strategies fail to identify over 30% (17,543 of 57,398) of children with subclinical lead poisoning and that accounting for characteristics at birth alters the conclusions about racial disparities in children's EBLLs. https://doi.org/10.1289/EHP10335.

The impact of lead poisoning from ammunition sources on raptor populations in Europe

Poisoning caused by ingestion of spent lead (Pb) ammunition in food items is a common cause of death of raptors. However, there has been no previous attempt to assess the impact of lead poisoning on populations of raptors throughout Europe or examine how this relates to the prevalence of hunting. We used measurements of lead concentration in the liver from over 3000 raptors of 22 species found dead or dying in the wild in 13 countries and a lead poisoning threshold of 20 ppm (dry weight) to assess the proportion of these in which lead poisoning caused or contributed to death. The prevalence of lead poisoning as a cause of death of raptors varied substantially among European countries and was positively correlated across countries with the reported number of hunters per unit area. Ten species had a non-zero proportion of individuals with concentrations exceeding the lead poisoning threshold ranging between 0.3% and 16.5%. The estimated annual conditional death rate from lead poisoning for these ten species averaged 0.44% (range 0.06-0.85%). Scavenging species feeding regularly on carcasses of game animals,tended to have a high annual probability of death from lead poisoning. So too did some predators which only sometimes scavenge, but prey on frequently hunted birds, such as gamebirds, waterfowl and pigeons, which may contain ingested or embedded lead shot. Small-bodied predators had a low annual probability of death from lead poisoning. Modelling indicated that European populations of adult raptors of the ten focal species averaged 6.0% smaller (range 0.2-14.4%) than they would be without the effects of lead poisoning. A given rate of lead poisoning mortality resulted in greater expected population reductions for species with high annual survival rate and late age at first breeding.

Using Small Area Prevalence Survey Methods to Conduct Blood Lead Assessments among Children

Introduction: Prevalence surveys conducted in geographically small areas such as towns, zip codes, neighborhoods or census tracts are a valuable tool for estimating the extent to which environmental risks contribute to children’s blood lead levels (BLLs). Population-based, cross-sectional small area prevalence surveys assessing BLLs can be used to establish a baseline lead exposure prevalence for a specific geographic region. Materials and Methods: The required statistical methods, biological and environmental sampling, supportive data, and fieldwork considerations necessary for public health organizations to rapidly conduct child blood lead prevalence surveys at low cost using small area, cluster sampling methodology are described. Results: Comprehensive small area prevalence surveys include partner identification, background data collection, review of the assessment area, resource availability determinations, sample size calculations, obtaining the consent of survey participants, survey administration, blood lead analysis, environmental sampling, educational outreach, follow-up and referral, data entry/analysis, and report production. Discussion: Survey results can be used to estimate the geographic distribution of elevated BLLs and to investigate inequitable lead exposures and risk factors of interest. Conclusions: Public health officials who wish to assess child and household-level blood lead data can quickly apply the data collection methodologies using this standardized protocol here to target resources and obtain assistance with these complex procedures. The standardized methods allow for comparisons across geographic areas and over time.

Investigating aluminum cookpots as a source of lead exposure in Afghan refugee children resettled in the United States

BACKGROUND

Afghan refugee children resettled in Washington State have the highest prevalence of elevated blood lead levels (BLLs) of any other refugee or immigrant population. Resettled families brought several lead-containing items with them from Afghanistan, including aluminum cookpots.

OBJECTIVES

To evaluate the potential contribution of lead-containing cookpots to elevated BLLs in Afghan children and determine whether safer alternative cookware is available.

METHODS

We screened 40 aluminum cookpots for lead content using an X-ray fluorescence (XRF) analyzer and used a leachate method to estimate the amount of lead that migrates into food. We also tested five stainless steel cookpots to determine whether they would be safer alternatives.

RESULTS

Many aluminum cookpots contained lead in excess of 100 parts per million (ppm), with a highest detected concentration of 66,374 ppm. Many also leached sufficient lead under simulated cooking and storage conditions to exceed recommended dietary limits. One pressure cooker leached sufficient lead to exceed the childhood limit by 650-fold. In contrast, stainless steel cookpots leached much lower levels of lead.

SIGNIFICANCE

Aluminum cookpots used by refugee families are likely associated with elevated BLLs in local Afghan children. However, this investigation revealed that other U.S. residents, including adults and children, are also at risk of poisoning by lead and other toxic metals from some imported aluminum cookpots.

IMPACT STATEMENT

Some aluminum cookware brought from Afghanistan by resettled families as well as cookpots available for purchase in the United States represent a previously unrecognized source of lead exposure.

Role of environmental lead in the occurrence of anemia in Indian children: a systematic review and meta-analysis

Exposure to lead among children, as well as adults, is a major global health issue. With diverse routes of exposure (e.g., food, air, and water) either environmentally or occupationally, lead among children can cause mild, moderate, to severe health complications in the later stages of life. The average blood lead level reported by CDC in 2021 is 3.5 µg/dL, and the level of blood lead toxicity is ≥ 10 μg/dL. In this study, we planned to systematically analyze the association between blood lead levels (BLLs) (≥ 10 μg/dL and < 10 μg/dL) and the risk of anemia (hemoglobin level < 11 g/dL) among Indian children aged between ≥ 1 and ≤ 18 years. An online literature search of 5 databases, PubMed, Ovid, EMBASE, Web of Science, and Google Scholar was accomplished with a search updated until 8^th March 2021. Study designs included cohort, cross-sectional, and case-control studies that have evaluated the association of lead toxicity or exposure with anemia (Hb < 11 g/dL) reported in urban and/or rural Indian children. Meta-analysis was performed among a total of 864 children from 4 cross-sectional studies. The association between lead toxicity (BLLs ≥ 10 μg/dL) and the risk of being anemic was not statistically significant (RR = 1.15 (95% CI: 0.86-1.55, I² = 77%). The risks of bias in all included studies were low according to the Newcastle Ottawa Scale. Increased blood lead levels did not appear to be the major contributor to anemia in Indian Children. We need to focus primarily on improving the nutritional quality, fortified food supplements, and a balanced diet for children to reduce the anemia burden in India. Lead toxicity should be sought as an etiological factor only in areas of high environmental risk factors which were leaded paints, leaded batteries, a house near major road/traffic areas, and pesticide exposure.

Correlation of Lead Poisoning and Intelligence Status of School Children in a Southern Nigerian Urban City

BACKGROUND

Lead is a heavy metal of utmost public health significance in Nigeria. It is a known neurotoxin that impairs neurotransmission and brain function resulting in cognitive and motor deficits. Ingestion of lead contaminated food or water is the major route of exposure to lead manifesting as neurologic symptoms which can interfere with the intelligence of school children.

AIM

To correlate the Intelligence quotient scores with the blood lead levels of primary school children in Southern Nigeria.

METHODS

The study was a descriptive cross-sectional study amongst primary school pupils, conducted in Asaba, the capital of Delta state, Nigeria. Goodenough-Harris "Draw a Person Test" validated by Ebigbo and Izuora in Enugu, Nigeria was used to assess the intelligence of the pupils while blood lead levels was measured with Flame Atomic Absorption Spectrophotometer (FAAS).

RESULTS

Three hundred and twenty subjects were recruited. Seventy-one subjects did not have lead poisoning (22%) while two hundred and forty-nine subjects had lead poisoning (77.8%). Mild, moderate and severe level lead poisoning constituted 22.5% (56/249), 28.1% (70/249) and 49.4% (123/249) respectively. Seventy percent (225) subjects had optimal IQ while 95 subjects had sub-optimal IQ and mean IQ score was 92.9 ± 25.1. There was no association and correlation between IQ status and levels of lead poisoning.

CONCLUSION

A significant proportion of school children had optimal level of intelligence despite the high prevalence of lead poisoning seen among them. There was no association or correlation between different levels of childhood lead poisoning and Intelligence quotient status.

Blood lead levels and lead toxicity in children aged 1-5 years of Cinangka Village, Bogor Regency

Lead is one of ten hazardous chemicals of public health concern and is used in more than 900 occupations, including the battery, smelting, and mining industries. Lead toxicity accounts for 1.5% (900,000) of deaths annually in the world. In Indonesia, reports of high Blood Lead Level (BLL) were associated with residency in Used Lead Acid Battery (ULAB) recycling sites. The present study aims to investigate the BLL and the evidence of lead toxicity of children living in an ULAB recycling site in Bogor Regency, Indonesia. A cross-sectional study involving 128 children aged 1–5 years was conducted in September-October 2019. The socio-economic factors, BLL, nutritional status, and hematological parameters, were evaluated. Data were analyzed by univariate and bivariate using the Chi-Square test. Socio-economic factors revealed only 2.3% children have pica and 10.9% children have hand-to-mouth habits. Majority of parents had low income, education, and have stayed in the village for years. Analysis on BLL revealed that 69.5% children had BLL of >10 μg/dL, 25% had abnormal BMI, 23.4% had underweight, 53.9% had stunting, 33.6% had anemia, and 22.6% had basophilic stippling. The average BLL and hemoglobin levels of respondents were 17.03 μg/dL and 11.48 g/dL, respectively. Bivariate analysis revealed that children with high BLL had double risk of having underweight and protected from stunting. Analysis on the association between BLL and BMI for age revealed a higher risk to have abnormal BMI. The high BLL also had 1.017 times risk of developing anemia, and almost doubled risk of having basophilic stippling, although they were not statistically significant. In conclusion, the high BLL of children living in the ULAB recycling indicates that lead exposure as well as lead toxicity are still occurring in Cinangka Village, and alerts to the need for a systematic action to mitigate the exposure.

A new approach to a legacy concern: Evaluating machine-learned Bayesian networks to predict childhood lead exposure risk from community water systems

Lead in drinking water continues to put children at risk of irreversible neurological impairment. Understanding drinking water system characteristics that influence blood lead levels is needed to prevent ongoing exposures. This study sought to assess the relationship between children's blood lead levels and drinking water system characteristics using machine-learned Bayesian networks. Blood lead records from 2003 to 2017 for 40,742 children in Wake County, North Carolina were matched with the characteristics of 178 community water systems and sociodemographic characteristics of each child's neighborhood. Bayesian networks were machine-learned to evaluate the drinking water variables associated with blood lead levels ≥2 μg/dL and ≥5 μg/dL. The model was used to predict geographic areas and water utilities with increased lead exposure risk. Drinking water characteristics were not significantly associated with children's blood lead levels ≥5 μg/dL but were important predictors of blood lead levels ≥2 μg/dL. Whether 10% of water samples exceeded 2 ppb of lead in the most recent year prior to the blood test was the most important water system predictor and increased the risk of blood lead levels ≥2 μg/dL by 42%. The model achieved an area under the receiver operating characteristic curve of 0.792 (±0.8%) during ten-fold cross validation, indicating good predictive performance. Water system characteristics may thus be used to predict areas that are at risk of higher blood lead levels. Current drinking water regulatory thresholds for lead may be insufficient to detect the levels in drinking water associated with children's blood lead levels.

Evaluating Housing Characteristics Associated With Childhood Lead Exposure in Providence, Rhode Island

OBJECTIVE

This research aims to take an in-depth look into the child, housing, and neighborhood characteristics associated with Providence children's likelihood of having elevated blood lead levels (BLLs).

DESIGN AND SETTING

The 2019 Providence, Rhode Island, Property Tax Assessor's database, containing each property owner's address, was geocoded and spatially joined with the 2017-2019 blood lead tests for children aged 0 to 6 years from the Rhode Island Department of Health.

MAIN OUTCOME MEASURES

The prevalence of elevated BLLs (≥5 μg/dL) overall, as well as by property type, number of properties owned, owner occupancy, assessed value, and neighborhood rates of old housing and poverty, was computed. We assessed the relationship between having elevated BLLs and these housing and neighborhood characteristics, adjusting for gender, age at test, and test method.

RESULTS

We found that, compared with children living in properties with landlords who owned only one property, children living in properties with landlords who owned 4 or more properties had lower odds of having elevated BLLs (odds ratio = 0.98; 95% confidence interval, 0.97-0.99). The proportion of houses built pre-1950 in the neighborhood was associated with increased odds of elevated BLLs. There was no significant association between owner-occupancy status and property type with children having elevated BLLs.

CONCLUSIONS

Children living in properties with landlords who owned 4 or more properties were less likely to have elevated BLLs. This association may suggest that the current lead legislation is having some impact, but public health efforts should address lead exposure in properties that are currently exempt from the law.

An Observational Study of the Association Between Exposure to Vacant Building Demolitions and Elevated Blood Lead Levels in Children Under Six in St Louis City

CONTEXT

St Louis City has been demolishing vacant buildings at an increasing rate. Demolition can cause lead dust spread, and childhood lead exposure can have negative effects on cognition, growth, and development. Previous studies show an association between exposure to multiple demolitions and elevated blood lead levels (EBLLs) in children, but St Louis City does not monitor the effects of demolitions on children's blood lead levels.

OBJECTIVES

The purpose of this study was to measure the association between exposure to demolitions and EBLLs in children younger than 6 years in St Louis City from 2017 to 2020.

DESIGN/SETTING/PARTICIPANTS

We analyzed blood lead testing data for children 0 to 72 months of age (n = 22 192) and proximity to demolitions. Exposure was the presence of demolitions within 400 ft of a child's address in the 33 days before their first lead test.

MAIN OUTCOME MEASURE

We used logistic regression to test the association between proximity to demolition and EBLLs (≥5 µg/dL).

RESULTS

The percentage of children living in proximity to 1 or more demolitions was slightly higher among those with EBLLs (n = 21; 1.3%) than among those without EBLLs (n = 250; 1.2%). However, after adjusting for age, sex, year home was built, season, neighborhood socioeconomic percentile, and neighborhood racial composition, the odds of EBLLs were not significantly different for children exposed to 1 or more demolitions (OR = 0.82; 95% CI, 0.5-1.25) compared with exposed to zero demolitions.

CONCLUSIONS

Although this study found no association between exposure to demolitions and EBLLs, results should be interpreted with caution, given numerous limitations. Given the consequences of childhood lead exposure, it is recommended that St Louis City conduct a similar analysis on demolitions conducted after 2020 using systematically collected demolition dates. Targeted testing or soil and air monitoring could also be informative.

[Analysis of suspected occupational chronic lead poisoning reported online and subsequent diagnosis in Jiangsu Province from 2014 to 2018]

Objective: To understand the distribution and characteristics of suspected occupational chronic lead poisoning reported online by Jiangsu Province, and to track the final diagnosis of suspected cases. Methods: The suspected occupational chronic lead poisoning cases in Jiangsu Province reported online from 2014 to 2018 were collected as the survey objects. Based on the reporting of the Occupational Disease Report Card from January 1, 2014 to November 5, 2019, the distribution characteristics and reporting institutions of suspected cases and final confirmed cases were analyzed. Results: From 2014 to 2018, 312 cases of suspected occupational chronic lead poisoning were reported online in Jiangsu Province. There were significant differences in the number of online reported cases of occupational chronic lead poisoning, online reported cases of suspected occupational chronic lead poisoning and confirmed cases of suspected occupational chronic lead poisoning in different years (P<0.05) , especially in 2015. Among the suspected occupational lead poisoning cases reported online, 236 cases (75.6%) were male, mainly distributed in the manufacturing industry, and 246 cases (79.1%) were operators. All the suspected occupational chronic lead poisoning cases reported online were concentrated in private enterprises, 229 cases (73.4%) in small and medium-sized enterprises. The top three cities were Suqian with 111 cases (35.6%) , Yangzhou with 79 cases (25.3%) and Huai'an with 50 cases (16.0%) . From 2014 to 2018, 19 suspected cases of occupational chronic lead poisoning were finally confirmed in Jiangsu Province, with a diagnosis rate of 6.1%. Conclusion: The majority of suspected occupational chronic lead poisoning cases reported online in Jiangsu Province are men, manufacturing and small and medium-sized enterprises, and the final diagnosis rate of suspected occupational chronic lead poisoning cases reported online is low.

Uneven development of the lead industry leads to regional differences in blood lead levels of children

Children's exposure to lead is a global health problem, especially in low- and middle-income countries. However, research on the relationship between children's blood lead levels (BLLs) and the development of the lead industry is still limited. This study examined whether children's BLLs were associated with the development of lead industry in different regions. Using survey data on the BLLs of children living in 250 prefectures in China with corresponding data on their economic factors and lead industries, we explored the regional variation of children's BLLs using statistical methods. The results show that the level of economic development in leaded areas was associated with inequity in children's BLLs and met the environmental Kuznets hypothesis. In areas without lead industries, there was little correlation between the level of economic development and the BLLs of children and thus the environmental Kuznets hypothesis was not supported. Lead mines, lead smelting and chemical companies are major sources of blood lead in children living in leaded areas. This study demonstrated the success of control policies for lead-acid battery manufacturers in promoting the prevention and control of childhood lead poisoning in China. China should consciously support the improvement of children's BLLs in undeveloped areas with lead industries through national financing and policies to avoid the continuous effects of the regional inequality problem of high children's BLLs.

Trend in blood lead levels in Taiwanese adults 2005-2017

This study examined the trend of blood lead levels (BLLs) in Taiwanese adults and analyzed the variations in the BLL between Linkou (northern) and Kaohsiung (southern) hospital branches. Between 2005 and 2017, 3,804 adult participants received blood lead tests at the Linkou (n = 2,674) and Kaohsiung (n = 1,130) branches of Chang Gung Memorial Hospital. The geometric mean of BLL was 2.77 μg/dL. The adult participants from the Kaohsiung branch were not only age older (49.8±14.1 versus 39.4±14.2 years; P<0.001) and male predominant (65.8 versus 41.7%; P<0.001) but also showed a higher BLL (4.45±3.93 versus 2.82±2.42 μg/dL; P<0.001) and lower estimated glomerular filtration rate (87.62±25.94 versus 93.67±23.88; P<0.001) than those from the Linkou branch. Multivariable logistic regression analysis revealed that the Kaohsiung branch [odds ratio (OR): 7.143; 95% confident interval (CI): 5.682–8.929; P<0.001], older age (OR: 1.008; 95% CI: 1.000–1.015; P = 0.043) and reduced estimated glomerular filtration rate (OR: 1.009; 95% CI: 1.004–1.014; P = 0.001) were significant predictors for BLL > 5 μg/dL. Therefore, this study confirmed a continuous decreasing trend in the BLL in Taiwan after banning leaded petrol in 2000.

Major lead exposure from hunting ammunition in eagles from Sweden

Exposure to lead (Pb) from ammunition in scavenging and raptorial birds has achieved worldwide recognition based on incidences of lethal poisoning, but exposure implies also sublethal levels with potential harmful effects. Background and elevated Pb levels in liver from 116 golden eagles (GE, Aquila chrysaetos) and 200 white-tailed sea eagles (WTSE, Haliaeetus albicilla) from Sweden 2003-2011 are here examined, with supporting data from a previous WTSE report and eagle owl (EO, Bubu bubo) report. GE and WTSE display seasonal patterns, with no Pb level exceeding a generally accepted threshold for subclinical effects during summer but strongly elevated levels from October. Fledged juveniles show significantly lower levels than all other age classes, but reach levels found in older birds in autumn after the start of hunting seasons. Pb levels in EO (non-scavenger) show no seasonal changes and indicate no influence from ammunition, and are close to levels observed in juvenile eagles before October. In all, 15% WTSE and 7% GE were lethally poisoned. In areas with high-exposure to hunting ammunition, 24% of WTSE showed lethal Pb levels, compared to 7% in both eagle species from low-exposure areas. Lethal poisoning of WTSE remained as frequent after (15%) as before (13%) a partial ban on use of Pb-based shotgun ammunition over shallow waters (2002). Pb levels increased significantly in WTSE 1981-2011, in contrast to other biota from the same period. A significant decrease of Pb in WTSE liver occurred below a threshold at 0.25 μg/g (dry weight), exceeded by 81% of the birds. Trend patterns in Pb isotope ratios lend further support to this estimated cut-off level for environmental background concentrations. Pb from spent ammunition affects a range of scavenging and predatory species. A shift to Pb-free ammunition to save wildlife from unnecessary harm is an important environmental and ethical issue.

Reduction in Blood Lead Concentration in Children across the Republic of Georgia following Interventions to Address Widespread Exceedance of Reference Value in 2019

In recent years, reports of lead contamination have dramatically increased in Georgia. Given concerns about the exposure of children to lead (Pb), the National Multiple Indicator Cluster Survey (MICS-2018) included a blood sampling component. The results showed that 41% of the children that participated had blood Pb levels (BLL) ≥ 5 µg/dL and that BLL in children living in Western Georgia were higher than those in Eastern regions. In response to these findings, NCDC implemented written and verbal advice to the families of children who participated in the MICS-2018 on how to reduce Pb exposure. From August 2019 onwards, the state program of clinical follow-up was implemented. The design of this study was a longitudinal study. The intervention of interest was the public health advice and medical follow-up, and the outcome was defined as the difference in BLL between the MICS-2018 survey and the state program follow-up. We observed a significant overall reduction in median BLL between MICS-2018 and state program follow-up in both August 2019 and the latest results (until December 2019). However, we did not observe any significant further reduction between August and the most recent BLL results. In the Georgian setting, written and verbal communication targeting individual households, alongside home visits to the most exposed, effectively reduced BLL in children.

Identifying Jurisdictions at Risk of Containing Housing Units With Deteriorated Paint: Results and Targeting Implications for the US Department of Housing and Urban Development

CONTEXT

The US Department of Housing and Urban Development provides millions in annual funding to make low-income housing lead safe, but funds are limited relative to need. To adequately target efforts, local program administrators must identify neighborhoods that are the most "at risk" of residential lead exposure; however, no federal agency currently provides a public data set for this use.

OBJECTIVES

To examine pre-1980 households with large areas of deteriorated paint, a significant and common predictor of lead dust, and identify high-risk jurisdictions. To highlight the potential use of a newly available data set for strategic lead poisoning prevention and targeting.

DESIGN

Microdata from the 2011 American Housing Survey and the 2009-2013 American Community Survey were used to develop a household-level predicted risk metric that identifies housing units at risk of containing large areas of deteriorated paint. Predicted risk, defined as the mean predicted percentage of occupied housing units at risk of containing deteriorated paint within a given jurisdiction, was summarized by state, county, and tract.

SETTING

National, all occupied housing units.

PARTICIPANTS

Occupied housing units summarized by household (n = 9 363 000), census tract (n = 72 235), county (n = 3143), and state (n = 51).

MAIN OUTCOME MEASURE

Housing units built prior to 1980 with a large area of deteriorated paint.

RESULTS

New York, Rhode Island, New Jersey, Massachusetts, and Pennsylvania had the highest predicted percentage of at-risk households (range: 2.52%-2.90%). County-level and tract-level estimates are the most useful when examining a predefined jurisdiction; New York state was presented as a case study. County-level quartile risk scores revealed Albany as an at-risk jurisdiction. Tract-level quartile risk scores further identified at-risk neighborhoods in northeastern Albany.

CONCLUSIONS

Findings can help housing and health policy makers identify and target geographic areas with a high probability of households at risk of potential exposure to deteriorated lead-based paint.

Lead Poisoning among Male Juveniles Due to Illegal Mining: A Case Series from South Africa

Illegal mining is a major public health and societal concern. Recent scientific evidence indicates elevated blood–lead levels in illegal gold miners and associated communities. Yet, there is little research in this regard from low- to middle-income countries (LMICs), where illegal mining is growing. This case series is extracted from a cross-sectional study of lead exposure in incarcerated juveniles in greater Johannesburg. From survey records (blood–lead levels and questionnaires), three males had elevated blood–lead levels and presented with health conditions and behavioural problems putatively linked with lead poisoning. Based on the record review, all three juveniles were in a secure facility due to illegal mining-related activities. All three cases had high blood–lead levels and demonstrated a tendency toward aggressive or violent behaviour. They also presented with conditions associated with lead poisoning, such as anaemia, respiratory illness, abdominal disorders, and musculoskeletal conditions. Juveniles involved in illegal mining are at risk of exposure to heavy metals such as lead, and there is a need for relevant preventative action and health care programmes in this group.

Retained bullet fragments after nonfatal gunshot wounds: epidemiology and outcomes

BACKGROUND

With no consensus on the optimal management strategy for asymptomatic retained bullet fragments (RBF), the emerging data on RBF lead toxicity have become an increasingly important issue. There are, however, a paucity of data on the magnitude of this problem. The aim of this study was to address this by characterizing the incidence and distribution of RBF.

METHODS

A trauma registry was used to identify all patients sustaining a gunshot wound (GSW) from July 1, 2015, to June 31, 2016. After excluding deaths during the index admission, clinical demographics, injury characteristics, presence and location of RBF, management, and outcomes, were analyzed.

RESULTS

Overall, 344 patients were admitted for a GSW; of which 298 (86.6%) of these were nonfatal. Of these, 225 (75.5%) had an RBF. During the index admission, 23 (10.2%) had complete RBF removal, 35 (15.6%) had partial, and 167 (74.2%) had no removal. Overall, 202 (89.8%) patients with nonfatal GSW were discharged with an RBF. The primary indication for RBF removal was immediate intraoperative accessibility (n = 39, 67.2%). The most common location for an RBF was in the soft tissue (n = 132, 58.7%). Of the patients discharged with an RBF, mean age was 29.5 years (range, 6.1-62.1 years), 187 (92.6%) were me, with a mean Injury Severity Score of 8.6 (range, 1-75). One hundred sixteen (57.4%) received follow-up, and of these, 13 (11.2%) returned with an RBF-related complication [infection (n = 4), pain (n = 7), fracture nonunion (n = 1), and bone erosion (n = 1)], with a mean time to complication of 130.2 days (range, 11-528 days). Four (3.4%) required RBF removal with a mean time to removal of 146.0 days (range, 10-534 days).

CONCLUSION

Retained bullet fragments are very common after a nonfatal GSW. During the index admission, only a minority are removed. Only a fraction of these are removed during follow-up for complications. As lead toxicity data accumulates, further follow-up studies are warranted.

LEVEL OF EVIDENCE

Prognostic and epidemiological, level III.