Impact of the COVID-19 Pandemic on Blood Lead Testing in Children in the United States.

The study objective was to evaluate the impact of the coronavirus disease (COVID-19) pandemic on pediatric blood lead testing in the United States. Clinical laboratory pediatric (ages <6 years) blood lead level (BLL) tests performed by Quest Diagnostics, January 2019-March 2022, were analyzed. Patients were categorized by age, by sex, and, through matching by ZIP code with US Census data, for race, ethnicity, pre-1950 housing, and poverty estimates. Over 2.8 million results from children (<6 years old) from all 50 states and the District of Columbia were included. Compared to March-May 2019, BLL testing was lower by 53.6% in March-May 2020 and lower by 14.6% in March-May 2021. Testing rebounded more for children in predominantly White non-Hispanic communities and among children living in communities, based on ZIP codes, with the least pre-1950 housing stock and lowest poverty rates. The proportion of children with BLL at or above the United States Centers for Disease Control and Prevention reference values of 3.5 and 5.0 µg/dL fell by 19% and 24%, respectively, in 2021 versus 2019. In conclusion, pediatric BLL testing has rebounded from sharp declines during the early pandemic period but unevenly. Declines in the proportion of children with elevated BLL should be interpreted with caution, as testing rebounds were less robust among communities with the highest risk of lead poisoning, notably communities with the oldest housing stock and higher poverty rates. More public health efforts are needed to address lead toxicity throughout the United States, especially in communities that did not experience a full rebound subsequent to the early COVID-19 pandemic period.

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.

Blood cadmium, lead, manganese, mercury, and selenium levels in American Indian populations: The Strong Heart Study.

BACKGROUND: Many American Indian (AI) communities are in areas affected by environmental contamination, such as toxic metals. However, studies assessing exposures in AI communities are limited. We measured blood metals in AI communities to assess historical exposure and identify participant characteristics associated with these levels in the Strong Heart Study (SHS) cohort. METHOD: Archived blood specimens collected from participants (n = 2014, all participants were 50 years of age and older) in Arizona, Oklahoma, and North and South Dakota during SHS Phase-III (1998-1999) were analyzed for cadmium, lead, manganese, mercury, and selenium using inductively coupled plasma triple quadrupole mass spectrometry. We conducted descriptive analyses for the entire cohort and stratified by selected subgroups, including selected demographics, health behaviors, income, waist circumference, and body mass index. Bivariate associations were conducted to examine associations between blood metal levels and selected socio-demographic and behavioral covariates. Finally, multivariate regression models were used to assess the best model fit that predicted blood metal levels. FINDINGS: All elements were detected in 100% of study participants, with the exception of mercury (detected in 73% of participants). The SHS population had higher levels of blood cadmium and manganese than the general U.S. population 50 years and older. The median blood mercury in the SHS cohort was at about 30% of the U.S. reference population, potentially due to low fish consumption. Participants in North Dakota and South Dakota had the highest blood cadmium, lead, manganese, and selenium, and the lowest total mercury levels, even after adjusting for covariates. In addition, each of the blood metals was associated with selected demographic, behavioral, income, and/or weight-related factors in multivariate models. These findings will help guide the tribes to develop education, outreach, and strategies to reduce harmful exposures and increase beneficial nutrient intake in these AI communities.

Delta-Aminolevulinic Acid Dehydratase, Low Blood Lead Levels, Social Factors, and Intellectual Function in an Afro-Brazilian Children Community.

Delta-aminolevulinic acid dehydratase (ALAD) enzyme catalyzes the second phase of the heme biosynthesis and is involved in lead toxicokinetics. This research aimed to evaluate its influence on the relationship between blood lead (PbB) levels and intellectual performance in Afro-Brazilian children. PbB, hemoglobin concentration, ALAD activity, and polymorphism were determined in whole blood. Anthropometric, socioeconomic, and family environment stimuli data were collected with appropriate instruments. The non-verbal intelligence of children and their mothers or guardians was assessed using the correspondent Raven's Progressive Matrix versions. The medians (range) of PbB levels and ALAD activity were 1.0 µg/dL (0.1-21.3) and, 71 U/L (31-113), respectively. ALAD G177C was distributed as follows: 97.9% for ALAD1/1 and 2.1% for ALAD1/2 genotypes. The mean of Raven raw score was 19.3 (± 5.6) points and there were no differences according to sex or environmental Pb exposure. No statistically significant association was observed between PbB level and children's IQ. However, ALAD activity presented an inverse significant association with PbB levels, children's percentile IQ, and children's IQ/Age ratio, suggesting a neuroprotective role of ALAD1 genotype in those with low PbB level.

Associations between welding fume exposure and blood hemostatic parameters among workers exposed to welding fumes in confined space in Chonburi, Thailand.

BACKGROUND: Occupational welding fumes contain varieties of toxic metal particles and may affect cardiovascular system like the Particulate Matters (PM). Few studies have focused on the effects of toxic metals on the hemodynamic balance; however, the reporting results were not consistent. This study aimed to investigate the association between toxic metals exposure (Chromium (Cr), Manganese (Mn) and Lead (Pb)) and blood hemostatic parameters status after a 3-week exposure cessation among workers exposed to welding fumes. METHODOLOGY: Structured interviews and biological samplings were conducted for 86 male workers without a history of Anemia and Cardiovascular diseases (CVDs) and working in a confined space to construct crude oil tanks. Metal levels of Cr, Mn and Pb in urine were measured during the working days using Inductively Coupled Plasma Mass Spectrometer (ICP-MS) method. The concentrations of hemostatic proteins in blood (White blood cell counts (WBC), Lymphocytes, Monocyte, Eosinophil, Neutrophil, Hematocrit (Hct) were assessed after a 3 weeks exposure cessation. Workers were divided into groups based on occupation type (welder group and non-welder group), and based on metal levels (high and low exposure groups) for comparison. Linear regression models were used to explore the association between metal exposure and multiple blood hemostatic parameters adjusted for age, Body Mass Index (BMI), and smoking status. RESULTS: Urine Mn and Cr level of the welder group was significantly higher than the non-welder group (Mn: 0.96 VS 0.22 ug/g creatinine, p < 0.001; Cr: 0.63 VS 0.22 ug/g creatinine, p < 0.01). The mean value of Hct in the welder group was 44.58 ± 2.84 vol%, significantly higher than the non-welder group (43.07 ± 3.31 vol%, p = 0.026). The median value of WBC in the high Mn-exposed group (6.93 ± 1.59 X 106 Cell/ml) was significantly lower than the low Mn-exposed group (7.90 ± 2.13 X 106 Cell/ml, p = 0.018). The linear regression analyses showed that there was a significantly negative association between log transformed WBC value and the Mn exposure groups (high and low) after adjusting for age, BMI, and smoking status (ß = - 0.049, p = 0.045), but no significant result was found between WBC and occupation types (welder and non-welder) (p > 0.05). Multiple linear regression analysis also showed positive association between Hct and occupational types (welder and non-welders) (ß = 0.014, p = 0.055). The other hemostatic parameters were not different from controls when divided by occupation type or metal level groups. CONCLUSIONS: Our results showed that welders were exposed to about 3 to 4 times higher Mn and Cr concentrations than non-welders. Moreover, one third of the non-welders were exposed to high-exposure groups of Mn and Cr metals. Regression models revealed a significant association of the WBC counts with the Mn exposure group. Therefore, we infer that Mn exposure may play a significant role on the blood hemostatic parameters of workers in the confined space. Hazard identification for non-welders should also be conducted in the confined space.

Efficacy and expenses of succimer vs. d-penicillamine plus garlic in the treatment of lead poisoning: a retrospective cross-sectional study.

PURPOSE: Lead Poisoning is a major health problem in Iran. We aimed to compare efficacy of a standard regimen (Succimer) with that of a low-priced combination of D-penicillamine and Garlic in outpatients with lead poisoning. METHODS: In this retrospective cross-sectional study, year-long clinical files of outpatients with lead poisoning in two referral toxicology clinics in Mashhad, Iran were reviewed. A total of 79 patients (all men), received either Succimer or a combination of D-penicillamen plus garlic (DPN + Gar), for 19 and 30 days, respectively. Clinical and laboratory data, including blood lead level (BLL), were analyzed and treatment expanses were compared between the two regimens. RESULTS: Of 79 male patients, 42 were treated by DPN + Gar and 37 received Succimer. Mean BLL of DPN + Gar group before treatment (965.73 ± 62.54 µg/L) was higher than that of the Succimer group (827.59 ± 24.41) (p < 0.001). After treatment, BLL in both groups significantly reduced to 365.52 ± 27.61 µg/L and 337.44 ± 26.34 µg/L, respectively (p < 0.001). The price of a 19-day treatment with Succimer was approximately 28.6 times higher than a one-month course of treatment with garlic plus DPN. None of the treatments caused serious side effects in the patients. CONCLUSION: Combination therapy with DPN + Gar is as effective as Succimer in Pb poisoning, while treatment with Succimer is significantly more expensive.

Blood Lead Levels and Associated Sociodemographic Factors among Children Aged 3 to 14 Years Living near Zinc and Lead Mines in Two Provinces in Vietnam.

Lead poisoning in children is a major public health concern worldwide, especially in developing countries. We conducted a cross-sectional study on 403 children aged from 3 to 14 years living nearly zinc-lead mining areas in two provinces in Vietnam (Bac Kan and Thai Nguyen) from 06/2016 to 10/2016 to identify risk factors for lead contamination. Results. The proportion of children with blood lead levels (BLLs) ≥ 10 µg/dL was 80.51% in Bac Kan and 50% in Thai Nguyen; the mean blood lead level for children was 14.41 ± 9.42 µg/dL. In linear regression analyses, the body mass index was negatively associated with elevated BLLs with r = -0.404, p < 0.05 (95% CI: -0.801, -0.006). In multivariable regression analysis, several risk factors were associated with lead contamination including male sex (aOR = 2.44, 95% CI: 1.13-5.24, p = 0.02), play areas in Bac Kan (aOR = 2.3 (1.02-5.17), p = 0.04), proximity of children's home of less than 2 kilometers from the mine (aOR = 2.90 (1.54-5.44), p = 0.001), and inattentive symptoms in Thai Nguyen (aOR = 7.85, 95% CI 3.49-17.69, p = 0.001). Environmental factors, including lead concentrations in the soil and ambient air samples in both locations, are many times higher than Vietnamese standards.

Patterns and Determinants of Essential and Toxic Elements in Chinese Women at Mid-Pregnancy, Late Pregnancy, and Lactation.

Maternal status of essential and toxic elements affects the health of the mother, developing fetus, or breastfeeding infant. However, few studies have examined the patterns of these elements and their determinants in pregnant or lactating women. Plasma samples of 1211 healthy mid-pregnant, late pregnant, and lactating women enrolled in coastland, lakeland, and inland areas of China from May-July 2014, were analyzed for concentrations of 15 elements, using inductively coupled plasma mass spectrometry. The adjusted median concentrations of elements varied by physiologic stage and region. Lactating versus pregnant women showed higher concentrations of Zn, Cr, Mo, Ni, Sb, Cd and Pb, but lower concentrations of Cu, I, Al and Hg. In pregnant women, the concentrations of Fe, Zn, I, Mo, Ni, Al, Hg and Cd were higher in mid- versus late-pregnancy. Overall, the highest concentrations were observed in Zn, I, Mn, Al, and Pb in coastland, in Hg in lakeland, and in Fe in inland area. Element concentrations varied by maternal age, pre-pregnancy BMI, education, parity, delivery mode, feeding practice, and intakes of aquatic products and mutton. In conclusion, essential and toxic elements coexisted in pregnant and lactating women, and their concentrations varied by physiologic stages, regions, maternal socio-demographic characteristics and dietary factors.

Soil Lead (Pb) in New Orleans: A Spatiotemporal and Racial Analysis.

Spatialized racial injustices drive morbidity and mortality inequalities. While many factors contribute to environmental injustices, Pb is particularly insidious, and is associated with cardio-vascular, kidney, and immune dysfunctions and is a leading cause of premature death worldwide. Here, we present a revised analysis from the New Orleans dataset of soil lead (SPb) and children's blood Pb (BPb), which was systematically assembled for 2000-2005 and 2011-2016. We show the spatial-temporal inequities in SPb, children's BPb, racial composition, and household income in New Orleans. Comparing medians for the inner city with outlying areas, soil Pb is 7.5 or 9.3 times greater, children's blood Pb is ~2 times higher, and household income is lower. Between 2000-2005 and 2011-2016, a BPb decline occurred. Long-standing environmental and socioeconomic Pb exposure injustices have positioned Black populations at extreme risk of adverse health consequences. Given the overlapping health outcomes of Pb exposure with co-morbidities for conditions such as COVID-19, we suggest that further investigation be conducted on Pb exposure and pandemic-related mortality rates, particularly among Black populations. Mapping and remediating invisible environmental Pb provides a path forward for preventing future populations from developing a myriad of Pb-related health issues.

Assessment of potters' occupational exposure to lead and associated risk factors in Maragogipinho, Brazil: preliminary results.

BACKGROUND AND PURPOSE: Lead (Pb) is used as a flux in the glazing process of pottery utensils in several regions of the world. It can affect the nervous and hematopoietic systems; in addition, it is classified as a probable human carcinogen. This work aims to evaluate Pb exposure of potters and describe the main determinants of elevated blood Pb (PbB) levels in this group of workers. METHODS: This is a cross-sectional study with potters of Maragogipinho Village, Bahia, Brazil, of both sexes, aged 16-72 years (n = 85). Non-exposed workers of the same age range residing in the urban area of Aratuípe town were also recruited (n = 50). We evaluated Pb dust deposition rates (PbDrt) in pottery workshops and PbB levels. All Pb measurements were performed by Graphite Furnace Atomic Absorption Spectrometry. RESULTS: The median of PbB (min-max) and geometric mean (SD) PbDrt for the exposed group were 7.9 (0.9-49.8) µg/dL and 1463 (± 290,000) µg/m2/30 days, respectively. For the control group, levels were 1.5 (0.1-19.8) µg/dL and 82 (46) µg/m2 30 days, respectively. CONCLUSION: The data found showed an excessive exposure among artisans, exceeding occupationally safe levels and those reported in the literature. It is important to implement occupational hygiene measures and improvements of the working conditions of these labors, especially the replacement of lead oxide in the pottery-glazing process.

Exploring persistent racial/ethnic disparities in lead exposure among American children aged 1-5 years: results from NHANES 1999-2016.

OBJECTIVE: The aim of this study was to determine whether long-standing racial disparities in lead exposure still exists for children age 1-5 years old. We examined if blood lead levels were higher among non-Hispanic Black children and others compared to non-Hispanic White children. METHODS: Data from the National Health and Nutrition Examination Survey (NHANES) from 1999-2016 were used. Geometric mean blood lead levels (BLLs) were compared by race/ethnicity using log-transformed simple linear regression. Associations between race and elevated BLL were assessed using weighted Chi-square tests. Log-transformed multiple weighted linear regression was used to assess what factors affected BLLs. RESULTS: A total of 6772 children were included in this study. In 1999-2000, the geometric mean BLL for non-Hispanic Black children was 3.08 µg/dL, compared to 2.03 µg/dL for non-Hispanic White children (p = 0.01). The difference in geometric mean BLL between non-Hispanic Black children and non-Hispanic White children continued to be statistically significant in later years (all p < 0.05) until 2015-2016 (0.89 µg/dL vs 0.74 µg/dL, p = 0.17). Log-transformed linear regression showed that being non-Hispanic Black and having low family income were independently associated with higher BLL. CONCLUSION: Although lead exposure in the general population continued to decline for all racial/ethnic groups, non-Hispanic Black children still had higher BLL than non-Hispanic White children. In more recent years, the racial/ethnic gap was lesser but persisted. Racial/ethnic disparity in childhood BLL could be partially explained by socio-economic factors.

Lead Poisoning Prevention Efforts in High-Risk Environments: Follow-up Testing Rates among Preschool Children in Flint, Michigan, 2013-2015.

OBJECTIVES: Despite the importance of screening in efforts to address lead poisoning, many children in the United States have never been tested for lead, even when required to receive blood lead testing by state and federal healthcare policy. Fewer children gain access to follow-up or confirmatory testing when elevated blood lead levels are detected. METHODS: In response to previous research that illustrates the extent to which follow-up treatment services have been underutilized and poorly coordinated, this retrospective cohort study examines follow-up testing trends for lead poisoning among Medicaid-enrolled children 6 years and younger in Flint, Michigan, between 2013 and 2015. RESULTS: These findings illustrate that compliance with follow-up testing procedures was less than adequate during the period of study. CONCLUSION: As illustrated in this bivariate analysis, subpopulations in Flint most likely to have lead poisoning were least likely to receive follow-up testing. Evidence also demonstrates that the likelihood that children with lead poisoning received follow-up testing was overwhelmingly associated with their blood lead concentration level than other indicators including socioeconomic status in this high-risk environment.

Umbilical Cord Blood Lead Level Disparities between Flint and Detroit.

OBJECTIVE: The lead-in-water impact of the Flint water crisis on the youngest and most neurodevelopmentally vulnerable population was largely unknown. The objective of this study was to investigate and compare cord blood lead levels (CBLLs) in newborns in Flint, Michigan, after the Flint water crisis, to a group of Detroit newborns. STUDY DESIGN: Mothers of 99 Flint newborns were surveyed about potential lead exposures. These neonates were born after the recognition of population-wide lead-in-water contamination. CBLLs were measured and maternal-fetal metrics were reviewed. CBLLs and maternal-fetal metrics were then compared with those of a retrospective cohort of 116 Detroit newborns who previously shared the same water source. Analysis involved descriptive statistics, independent t-test, and χ 2 analysis. RESULTS: CBLLs greater than or equal to 1 µg/dL (0.05 µmol/L) were more prevalent among Flint newborns (14%), as compared with Detroit newborns (2%; p = 0.001). This was a sevenfold disparity between Flint and Detroit newborns. No statistically significant differences were found in birth weight, head circumference, small for gestational age status, gestational age, or preterm status among the two groups. CONCLUSION: The Flint water crisis potentially exposed newborns to lead in utero, implicating maternal-fetal outcomes and future health and development. Primary prevention efforts, including identification and mitigation of lead exposure before conception and during pregnancy, are needed. New environmental exposure detection methods and long-term neurodevelopmental follow-up will complement the findings of this study.

Assessment of a Screening Questionnaire to Identify Exposure to Lead in Pregnant Women.

Lead readily crosses the placenta and displays adverse effects on birth outcomes and neurodevelopment. Systematic identification of the risk of exposure during pregnancy is essential but rarely performed, probably due to hospital staff's workload and their lack of awareness. We aimed to evaluate the relevance of a questionnaire to screen pregnant women for lead exposure. A cross-sectional, multicentre study was carried out on a population of 792 pregnant women from February 2018 to May 2020. A total of 596 women had a blood lead test: 68.5% had blood lead levels below 10 µg/L. The estimated prevalence above 25 µg/L was 4% (95% confidence interval (CI) [2.6-5.9]) and 1.3% had levels above 50 µg/L (95% CI [0.6-2.6]). Multivariate analysis showed that three risk factors significantly increased the probability of blood lead levels above 25 µg/L: the use of traditional cosmetics (adjusted odds ratio [aOR]: 3.90; 95% CI [1.65-9.21]; p = 0.002), degraded old housing (aOR: 2.67; 95% CI [1.19-6.038]; p = 0.018), and (marginally) eating bread more than twice a day (aOR: 2.40; 95% CI [0.96-6.11]; p = 0.060). Our study reveals that a three-question tool can be used to quickly screen for the risk of lead exposure in our population and to trigger lead blood tests and special vigilance during pregnancy follow-up.

Childhood maltreatment and lead levels in middle adulthood: A prospective examination of the roles of individual socio-economic and neighborhood characteristics.

BACKGROUND: Lead is a common environmental hazard because of its past use as an additive to gasoline and household paint. Some evidence suggests that children with histories of child abuse and neglect are at elevated risk for residence in communities and households with less desirable characteristics and high levels of exposure to environmental hazards and toxins. OBJECTIVES: To understand whether childhood maltreatment leads to higher levels of household dust lead and blood lead in adulthood and the extent to which characteristics of a person's physical environment or individual level socio-economic status (SES) (based on unemployment, poverty, and receipt of public assistance) contribute to understanding the relationship. METHODS: A large prospective cohort design study in which abused and neglected children (ages 0-11) were matched with non-maltreated children and assessed in adulthood. Objective and subjective neighborhood characteristics were assessed at approximate age 40 and household dust lead (cleaned and less often cleaned) and blood lead levels were measured at age 41. Blood was collected through venipuncture by a registered nurse as part of a medical status exam. RESULTS: Childhood maltreatment predicted higher levels of dust lead in less often cleaned household places, residence in worse neighborhoods defined by objective (census tract data) and subjective (reports of physical disorder and lack of social cohesion and control), and higher levels of poverty, receiving public assistance, and unemployment. Only objective neighborhood characteristics mediated the relationship between childhood maltreatment and dust lead level in adulthood. There were also significant paths from objective neighborhood disadvantage and individual level SES to higher levels of blood lead. DISCUSSION: Thirty years after their childhood experiences, individuals with documented histories of childhood maltreatment are at higher risk for living in environments as adults with elevated lead levels that may impact other aspects of their lives and compromise their health.

Children drinking private well water have higher blood lead than those with city water.

Although the Flint, Michigan, water crisis renewed concerns about lead (Pb) in city drinking water, little attention has been paid to Pb in private wells, which provide drinking water for 13% of the US population. This study evaluates the risk of Pb exposure in children in households relying on private wells. It is based on a curated dataset of blood Pb records from 59,483 North Carolina children matched with household water source information. We analyze the dataset for statistical associations between children's blood Pb and household drinking water source. The analysis shows that children in homes relying on private wells have 25% increased odds (95% CI 6.2 to 48%, P < 0.01) of elevated blood Pb, compared with children in houses served by a community water system that is regulated under the Safe Drinking Water Act. This increased Pb exposure is likely a result of corrosion of household plumbing and well components, because homes relying on private wells rarely treat their water to prevent corrosion. In contrast, corrosion control is required in regulated community water systems. These findings highlight the need for targeted outreach to prevent Pb exposure for the 42.5 million Americans depending on private wells for their drinking water.

Assessment of lead exposure controls on bridge painting projects using worker blood lead levels.

A retrospective analysis of worker blood lead levels (BLL) was conducted using blood lead data collected by four bridge painting contractors before and after lead exposure. The objective of the study was to evaluate the effectiveness of exposure controls in preventing elevated blood lead levels (>25 µg/dl) during bridge painting projects. The contractors selected for the study submitted BLL data for 289 workers representing ten work tasks and 11 bridge painting projects. In total, 713 blood lead levels results were evaluated. The mean blood lead level for all work classifications combined was 10.9 µg/dl at baseline compared with 14.9 µg/dl after two months of exposure and 15.0 µg/dl after four months of exposure. Two months after initial exposure, 29% of the painters and 35% of the laborers had a 10 µg/dl incremental increase or greater in blood lead level. Likewise, 18% of the painters and 26% of the laborers had a blood lead level greater than 25 µg/dl during the same time. The blood lead levels that exceeded the 25 µg/dL threshold ranged from 30µg/dL-63 µg/dL for painters and 26 µg-56 µg/dL for laborers. All work tasks with high-intensity exposure (abrasive blaster/painter, abrasive blaster, painter & laborer) experienced an average blood lead level increase that ranged from 0.2 µg/dl to 8.9 µg/dl two months after initial exposure. Blood lead testing conducted after modified exposure controls (two months after the initial follow-up blood testing) were implemented showed a decrease in average blood lead levels (range -0.14 µg/dl to -2.7 µg/dl) for two high-intensity exposure work tasks. In comparison, the other two high-intensity work tasks had moderate increases (range 1 µg/dl to 2.4 µg/dl). The modified exposure controls included an increase in the air velocity inside of the work containment and an administrative control in the form of additional worker training on lead exposure prevention. The reduction in the 95th percentile (point estimate) BLL exposure profile for each exposure group at the 4-month follow-up blood testing period is associated with modified exposure controls. Ineffective exposure controls were identified through the analysis of worker BLLs. We found two exposure groups (laborer and painter) whose 95th percentile (point estimate) exposure profile was greater than the OSHA construction lead standard's targeted BLL goal (25 µg/dl) during the first two months of exposure. Our research findings provide support for monthly blood lead testing after baseline until blood lead levels are controlled to an acceptable concentration.

Environmental exposure to lead and hematological parameters in Afro-Brazilian children living near artisanal glazed pottery workshops.

This study aimed to evaluate the exposure to environmental lead (Pb) of children from a traditional community of African descent in Brazil and the effects on hematological parameters. Children (n = 75) aged 5.5-13 years from the exposed areas classified as low (LEx) and moderately (MEx) exposed were compared with children (n = 75) of a control group (CG). Dust Pb loading rates (RtPbs) at children's homes were measured. Peripheral venous blood samples were collected to assess Pb biomarkers of exposure and effects. All Pb determinations were performed by graphite furnace atomic absorption spectrometry. The median (IQR) of RtPb, PbB level, and ALA-D activity were 65 (25-137) µgPb/m2/30 days, 1.0 (0.1-2.8) µg/dL, and 71 (55-86) U/L, respectively. Spearman correlation evidenced the relationship of PbB with RtPb (rho = 0.368, P < 0.001) and ALA-D activity (rho = -0.587; P ˂ 0.001). After adjusting for exposure degree and child's age, a decline of 7.4 U/L in ALA-D activity was associated with a 10-fold increase in PbB. The prevalence ratio of elevated PbB (>5 µg/dL) in LEx and MEx areas were 1.5 and 3.7, respectively. Indoor dust exposure, living near pottery workshops and the secondary exposure were the main determinants of elevated PbB levels, which were associated with hematological effects.

Lead and Mercury Exposure and Related Health Problems in Metal Artisan Workplaces and High-Risk Household Contacts in Thimphu, Bhutan.

BACKGROUND: Metal artisans have been using lead and mercury in their settings for centuries. Exposure to these toxic heavy metals causes adverse health effects. We assessed the occupational exposure of metal artisans and their high-risk household contacts at Thimphu, Bhutan. METHODS: A cross-sectional study in which 134 metal artisan center employees and 48 high-risk household contacts were tested for blood lead and mercury levels. Sociodemographic data, occupational exposure risk factors, and clinical syndrome related to lead and mercury exposure were further obtained and analyzed using EpiInfo 7.0. RESULTS: The mean age of the metal artisan center employees was 36.02 ± 10.3. The prevalence of elevated blood lead and mercury level was 38.4% and 51.9%, respectively. Significantly higher prevalence of mercury level was observed among the artisans compared to nonartisans (66.97 vs, 16.0). Among three centers, the goldsmith section of the Department of National Properties had the highest (94.1%). Profession as an artisan, mold designing, performing gold amalgamation, working for >8 hours a day, working for >5 years, and working at home were significant risk factors associated with elevated blood mercury level. Significant association was observed between elevated mercury level and complaints of burning or watery eyes (p=0.001), anxiety, nervousness, irritability, severe shyness (p=0.001), anxiety, nervousness, irritability, severe shyness (p=0.001), anxiety, nervousness, irritability, severe shyness (p=0.001), anxiety, nervousness, irritability, severe shyness (p=0.029), muscle aches (p=0.019), and stomach cramps or pain (p=0.009). CONCLUSION: The prevalence of elevated blood mercury level is concerning among the artisans. Advocacy, proper usage of personal protective equipment, awareness on chemical safety, and hazard associated with lead and mercury usage are needed to minimize the exposure.

Health Risk Assessment and Source Apportionment of Mercury, Lead, Cadmium, Selenium, and Manganese in Japanese Women: An Adjunct Study to the Japan Environment and Children's Study.

Toxic element pollution is a serious global health concern that has been attracting considerable research. In this study, we elucidated the major routes of exposure to three toxic elements (mercury, cadmium, and lead) and two essential elements (manganese and selenium) through diet, soil, house dust, and indoor air and assessed the potential health risks from these elements on women from the coastal area of Miyagi prefecture, Japan. Twenty-four-hour duplicate diet, house dust, soil, and indoor air samples were collected from 37 participants. Cd, Pb, Mn, and Se concentrations were measured using inductively coupled plasma mass spectrometry, and Hg concentrations using cold vapor atomic absorption spectrometry. We found that soil and house dust were the primary reservoirs of these elements. Diet contributed most strongly to the daily intake of these elements, with mean values of 0.72, 0.25, 0.054, 47, and 0.94 µg/kg/day for Hg, Cd, Pb, Mn, and Se, respectively. The mean hazard quotient of Hg was 1.53, indicating a high potential health risk from Hg exposure in daily lives. The intakes of other elements were below the tolerable limits. Future studies with a larger sample size are warranted to confirm our findings.