Blood Lead Levels and Potential Risk Factors for Lead Exposures Among South Asians in New York City

A Snapshot of Lead in Consumer Products Across Four US Jurisdictions

BACKGROUND

Following the removal of lead from gasoline, paint and pipes were thought to be the main sources of lead exposure in the United States. However, consumer products, such as certain spices, ceramic and metal cookware, traditional health remedies, and cultural powders, are increasingly recognized as important sources of lead exposure across the United States.

OBJECTIVE

This paper reviews data from four US jurisdictions that conduct in-home investigations for children with elevated blood lead levels (BLLs) to examine the prevalence of lead exposures associated with consumer products, in comparison with housing-related sources.

METHODS

Authors reviewed investigation data (2010-2021) provided by California, Oregon, New York City, and King County, Washington, and compared the extent of lead exposures associated with housing-related vs. consumer products-related sources.

DISCUSSION

The proportion of investigations identifying consumer products-related sources of lead exposure varied by jurisdiction (range: 15%-38%). A review of US CDC and US FDA alerts and New York City data indicates that these types of lead-containing products are often sourced internationally, with many hand carried into the United States during travel. Based on surveillance data, we believe that US immigrant and refugee communities are at an increased risk for lead exposures associated with these products. To engage health authorities, there is a need for evidentiary data. We recommend implementing a national product surveillance database systematically tracking data on consumer products tested by childhood lead poisoning prevention programs. The data repository should be centralized and accessible to all global stakeholders, including researchers and governmental and nongovernmental agencies, who can use these data to inform investigations. Effectively identifying and addressing the availability of lead-containing consumer products at their source can focus resources on primary prevention, reducing lead exposures for users abroad and in the United States. https://doi.org/10.1289/EHP14336.

Estimated Childhood Lead Exposure From Drinking Water in Chicago

Importance

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.

Objective

To identify the extent of lead-contaminated drinking water in Chicago, Illinois, and model its impact on children younger than 6 years.

Design, Setting, and Participants

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.

Exposure

Lead-contaminated drinking water, measured in parts per billion.

Main Outcomes and Measures

Number of children younger than 6 years exposed to lead-contaminated water.

Results

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.

Conclusions and Relevance

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.

Knowledge, Attitudes, Practices, and Prevention Barriers Related to Childhood Lead Poisoning Among Nepali-Speaking Bhutanese Parents in Northeast Ohio, United States

The study objectives were: (i) to develop and administer a survey to assess childhood lead poisoning (CLP) knowledge, attitudes, practices and prevention barriers (KAP-B) among the Nepali-Speaking Bhutanese (NSB) community in Northeast Ohio; and (ii) to examine the association between socio-demographic characteristics of NSB parents and their understanding of CLP as measured by the constructs of knowledge and attitudes. A Nepali language KAP-B questionnaire was developed and 200 NSB parents with at least one child ≤ 7 years of age from the Akron Metropolitan Area, Ohio were interviewed. NSB parents demonstrated a low level of knowledge about CLP prevention measures. While 82% lived in pre-1978 houses, only 27.5% perceived their house/neighborhood to be potentially lead contaminated. Only 33% of the parents reported understanding lead-related information provided by their child's healthcare provider. Low-level CLP awareness among NSB community emphasizes a need for culturally tailored and linguistically appropriate community-level CLP educational intervention programs in this vulnerable community.

Immigration and Blood Lead Levels Among Asian Populations in the United States: NHANES 2011-2018

OBJECTIVE

The aim of this study was to explore determinants of high BLLs among the Asian population in the United States.

METHODS

We used the US nationally representative National Health and Nutrition Examination Survey (NHANES), 2011-2018. We conducted stratified analyses to compare the BLLs of US-born and non-US-born Asians. We used adjusted linear regression to find predictors of high BLLs.

RESULTS

Among 12,563 participants in our analysis, the length of stay in the United States is a predictor of the gradual decrease in BLL among Asian immigrants ( P < 0.05). BLLs of immigrants who stayed in the United States for over 50 years were 0.36 μg/dL (95% confidence interval, 0.07 to 0.66) lower than new immigrants, but still higher than their US-born counterparts.

SIGNIFICANCE

Asian population in the US has the highest BLLs among all ethnic groups, and the exposure outside of the US among immigrants is likely the driver.

Testing the Multiple Disadvantage Model of Health with Ethnic Asian Children: A Secondary Data Analysis

This study of ethnic Asian children in the United States asked whether their health exhibited relationship with any of six factors: social disorganization, social structural factors, social relationships, the health of their parents, their access to medical insurance, acculturation. The sample of 1350 ethnic Asian children was extracted from the 2018 National Survey of Children's Health. Logistic regression results showed that these children's excellent/very good/good health was associated positively with safe neighborhoods, family incomes, family cohesiveness, family support, and receipt of Temporary Assistance for Needy Families (TANF). In turn, health was associated negatively with single-mother households. Implications of the present results in terms of interventions promoting family support, TANF participation, safe neighborhoods, and professionals' cultural competency are discussed.

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).

Effects of Individual and Neighborhood Characteristics on Childhood Blood Lead Testing and Elevated Blood Lead Levels, A Pennsylvania Birth Cohort Analysis

BACKGROUND

Despite declining lead exposure among U.S. children, childhood blood lead level (BLL) undertesting and elevation remains a public health issue. This study explores the impacts of maternal, infant, and neighborhood characteristics on the receipt of lead testing and having elevated BLLs (EBLLs) among children under age two.

METHODS

Pennsylvania infants born in 2015 and 2016 were followed to 24 months. Birth certificate data were linked to 2015 through 2018 blood lead surveillance data and neighborhood data on household income, poverty, and the burden of houses built before 1970. Generalized linear mixed models were used to examine the individual and neighborhood characteristics independently and/or interactively affecting the likelihood of lead testing and of having EBLLs.

RESULTS

A total of 48.6% of children were tested for BLLs, and 2.6% of them had confirmed EBLLs. The likelihood of lead testing and of having EBLLs among non-Hispanic black children was respectively 7% and 18% higher than white children. Children born to mothers with the lowest educational attainment (<high school), with self-payment as a payment source for delivery, and without WIC enrollment were at higher risk of undertesting. Children living in neighborhoods of the lowest quartile of household income and the highest quartile of poverty and old housing were more likely to have EBLLs. Different neighborhood characteristics modified the associations between some individual factors (such as race/ethnicity, payment source for delivery, and WIC enrollment) and the odds of undertesting and of having EBLLs.

CONCLUSION

This cohort analysis provides more accurate estimates of lead screening rates and the percentages of EBLLs than cross-sectional analysis. Some maternal and infant demographics significantly impact the risk of undertesting and of having EBLLs, and some of the effects vary across different neighborhood characteristics. These findings can help lead prevention programs to target screening and treatment resources to children with specific characteristics.

The urban lead (Pb) burden in humans, animals and the natural environment

Centuries of human activities, particularly housing and transportation practices from the late 19th century through the 1980's, dispersed hundreds of millions of tons of lead into our urban areas. The urban lead burden is evident among humans, wild and domesticated animals, and plants. Animal lead exposures closely mirror and often exceed the lead exposure patterns of their human partners. Some examples: Pigeons in New York City neighborhoods mimicked the lead exposures of neighborhood children, with more contaminated areas associated with higher exposures in both species. Also, immediately following the lead in drinking water crisis in Flint MI in 2015, blood lead levels in pet dogs in Flint were 4 times higher than in surrounding towns. And combining lead's neurotoxicity with urban stress results in well-characterized aggressive behaviors across multiple species. Lead pollution is not distributed evenly across urban areas. Although average US pediatric lead exposures have declined by 90% since the 1970s, there remain well defined neighborhoods where children continue to have toxic lead exposures; animals are poisoned there, too. Those neighborhoods tend to have disproportionate commercial and industrial lead activity; a history of dense traffic; older and deteriorating housing; past and operating landfills, dumps and hazardous waste sites; and often lead contaminated drinking water. The population there tends to be low income and minority. Urban wild and domesticated animals bear that same lead burden. Soil, buildings, dust and even trees constitute huge lead repositories throughout urban areas. Until and unless we begin to address the lead repositories in our cities, the urban lead burden will continue to impose enormous costs distributed disproportionately across the domains of the natural environment. Evidence-based research has shown the efficacy and cost-effectiveness of some US public policies to prevent or reduce these exposures. We end with a series of recommendations to manage lead-safe urban environments.

A Denver Refugee Clinic Blood Lead Level Analysis in Refugee Females of Reproductive Age, 13-45 years, 2014-2019

The objective was to determine if refugee females of reproductive age (FRA) are at risk of having elevated blood lead levels (BLL). A retrospective quality improvement project conducted at a Denver community health center (9/2014-3/2019) evaluated BLLs from initial domestic medical examinations (DME) in 312 FRA refugees (13-45 years). Associations between elevated BLL and demographic factors were explored using multivariable regression analysis. Of 312 FRA refugees, BLLs ranged from < 2.0 to 26.2 mcg/dL, 5% had elevated BLLs. Of pregnant refugees (49), 4% had elevated BLLs. Afghani country of origin was positively associated with elevated BLLs, adjusting for age (FRA: Prevalence Ratio 6.90 [2.68-17.77], p < 0.0001). Afghani FRA refugees, irrespective of pregnancy and breast-feeding status, should have BLL testing at DME. Nationally representative evaluations of FRA refugees are needed to determine if BLL screening should be expanded to all FRA refugees, irrespective of pregnancy or breast-feeding status.

Association between self-reported length of time in the USA and blood lead levels: National Health and Nutrition Examination Survey 2013-2016

OBJECTIVES

The aim of this study is to determine the association between length of time in the USA with blood lead (BPb).

DESIGN

Population-based cross-sectional study using data from the 2013-2016 National Health and Nutrition Examination Survey.

SETTING

USA.

PARTICIPANTS

5933 men and women (≥15 years); subgroups of men only (n=2867), women only (n=3064) and women of childbearing age (15-45 years) (n=1580).

PRIMARY AND SECONDARY OUTCOMES

The primary outcome was BPb concentration. The main exposure variable was self-reported number of years spent in the USA, categorised as: born in the USA; 0-4 years; 5-9 years; 10-19 years and ≥20 years. We used linear regression models adjusted for race/ethnicity, education, blood cotinine, age, sex (as appropriate) and accounted for complex survey design.

RESULTS

Women of childbearing age who have lived 0-4 years in the USA have, on average, a 54% (95% CI 36% to 75%) higher BPb compared with women born in the USA. Corresponding results for all women, men and the entire population were 49% (95% CI 34% to 66%), 49% (95% CI 28% to 75%) and 49% (95% CI 33% to 66%), respectively. Similar, statistically significant, results were observed for other time periods (5-9 years, 10-19 years and ≥20 years); the magnitude of the association decreased with increasing time in the USA.

CONCLUSIONS

This study provides additional evidence that newcomers to the USA may be a population at higher risk of elevated BPb.

Sources of lead exposure in various countries

This review evaluates the sources of lead exposure worldwide. Studies from searches relating to sources of lead exposure in various countries within different regional zones were reviewed. Results indicated that in Nigeria, exposure sources include electronic waste, paint and batteries. In Mexico exposure sources include glazed ceramics, lead contaminated utensils and lead contaminated water, for India lead sources include cosmetics and traditional medicines. Sources of lead exposure in China include e-waste, traditional medicines and industrial emissions. In France, exposure sources included lead paint from older homes, imported ceramics and cosmetics and industrial emissions. Australia's exposure sources include paint, dust, imported toys and traditional medicines. Finally, in the United States exposure sources included paint, the industrial legacy of lead exposure and batteries. In high-income countries (HICs) the legacy of lead exposure keeps populations continuously exposed. In lower- and middle-income countries (LMICs), in addition to the legacy of lead exposure, lack of regulations or the inability to enforce regulations keeps populations exposed. In all, evidence suggests that lead exposure remains an issue of public health significance in both HIC and LMIC.

Lead Exposure and Associated Risk Factors among New Migrant Children Arriving in Greece

Background: This study aims to assess lead exposure and associated risk factors among newly arrived migrant (M) (immigrant and refugees) children in Greece and a matched control of native (N) children. Methods: A prospective, cross-sectional study was performed in an outpatient clinic of a tertiary children’s hospital. Results: From 2010 to 2014, 598 children (M/N: 349/249) with a mean age of 6.96 years old (range 1–14, SD 3.76) were enrolled. Blood lead levels (BLLs) ranged from 0.7 to 21 μg/dL in migrant and from 0.4 to 10 μg/dL in native Greek children. Elevated BLLs ≥ 5 μg/dL were detected in 27.7% of migrants and 1.2% of natives (p < 0.001). A significant association was found between EBLLs and childrens’ age (≤5 years) (OR: 1.8, p-value 0.02) and EBLLs with Asian origin (OR: 3.63, p-value 0.023). Conclusion: New migrant children presented with increased BLLs when compared to their age- and sex-matched controls. Younger age and Asian origin were significant risk factors associated with elevated BLLs among children. Early screening, secondary prevention, and regular follow-up could prove useful in this vulnerable population.

Declines in adult blood lead levels in New York City compared with the United States, 2004-2014

OBJECTIVES

To assess changes in lead exposure in the New York City (NYC) adult population over a 10-year period and to contrast changes with national estimates, overall, and by socio-demographics and smoking status.

METHODS

We used measurements of blood lead levels (BLLs) from NYC resident adults who participated in the NYC Health and Nutrition Examination Surveys (HANES) in 2004 and 2013-2014. We compared estimates of geometric means (GM), 95th percentiles, and prevalence of BLL ≥ 5 µg/dL overall and by subgroups over time, with adults who participated in the National HANES (NHANES) 2001-2004 and 2011-2014.

RESULTS

The GM BLLs among NYC adults declined from 1.79 µg/dL in 2004 to 1.13 µg/dL in 2013-2014 (P < .0001). The declines over this period ranged from 30.1% to 43.2% across socio-demographic groups and smoking status (P < .0001 for all comparisons), and were slightly greater than declines observed nationally. The drop in prevalence of elevated BLLs (≥ 5 µg/dL) was also greater in NYC (4.8-0.5%), compared with NHANES (3.8-2.0%). By 2013-2014, NYC adults with lower annual family income (< $20,000) no longer had higher GM BLLs relative to those with higher incomes (≥ $75,000), a disparity improvement not observed nationally. Likewise, GM BLLs and 95th percentiles for non-Hispanic black adults in NYC were lower than GM BLLs for non-Hispanic white adults. Non-Hispanic Asian adults had the highest GM BLLs compared with other racial/ethnic groups, both in NYC in 2013-14 and nationally in 2011-2014 (1.37 µg/dL, P = .1048 and 1.22 µg/dL, P = .0004, respectively).

CONCLUSION

The lessening of disparity in lead exposure across income groups and decreasing exposure at the high end of the distribution among non-Hispanic black and Asian adults in NYC suggest that regulatory and outreach efforts have effectively targeted these higher exposure risk groups. However, Asian adults still had the highest average BLL, suggesting a need for enhanced outreach to this group. Local surveillance remains an important tool to monitor BLLs of local populations and to inform initiatives to reduce exposures in those at highest risk.