Improving prediction of linear regression models by integrating external information from heterogeneous populations: James-Stein estimators.

We consider the setting where (1) an internal study builds a linear regression model for prediction based on individual-level data, (2) some external studies have fitted similar linear regression models that use only subsets of the covariates and provide coefficient estimates for the reduced models without individual-level data, and (3) there is heterogeneity across these study populations. The goal is to integrate the external model summary information into fitting the internal model to improve prediction accuracy. We adapt the James-Stein shrinkage method to propose estimators that are no worse and are oftentimes better in the prediction mean squared error after information integration, regardless of the degree of study population heterogeneity. We conduct comprehensive simulation studies to investigate the numerical performance of the proposed estimators. We also apply the method to enhance a prediction model for patella bone lead level in terms of blood lead level and other covariates by integrating summary information from published literature.

Exploring the link between toxic metal exposure and ADHD: a systematic review of pb and hg.

INTRODUCTION: Attention-Deficit/Hyperactivity Disorder (ADHD) is a recognized neurodevelopmental disorder with a complex, multifactorial origin. Lead (Pb) and mercury (Hg) are highly toxic substances that can potentially impair brain development and have been implicated in the development of ADHD. This systematic review aims to analyze the epidemiological literature regarding the association between Pb and Hg exposure and the diagnosis of ADHD. METHODS: From November 1983 to June 2, 2023, a comprehensive search was conducted in multiple databases and search engines, including PubMed, Web of Science, Scopus, and Google Scholar. Observational studies (case-control, cohort, and cross-sectional) measuring Pb and Hg levels in various biological samples (blood, hair, urine, nail, saliva, teeth, and bone) of children with ADHD or their parents and their association with ADHD symptoms were included. RESULTS: Out of 2059 studies, 87 met the inclusion criteria and were included in this systematic review. Approximately two-thirds of the 74 studies investigating Pb levels in different biological samples reported associations with at least one subtype of ADHD. However, most studies examining Hg levels in various biological samples found no significant association with any ADHD subtype, although there were variations in exposure periods and diagnostic criteria. CONCLUSION: The evidence gathered from the included studies supports an association between Pb exposure and the diagnosis of ADHD, while no significant association was found with Hg exposure. Importantly, even low levels of Pb were found to elevate the risk of ADHD. Further research is needed to explore the comprehensive range of risk factors for ADHD in children, considering its significance as a neurodevelopmental disorder.

Association between blood lead, cadmium, selenium levels and hyperlipidemia: A population-based study.

BACKGROUND: There are limited epidemiological investigations of blood metal levels related to hyperlipidemia, and results indicating the association between blood lead (Pb), cadmium (Cd) and selenium (Se), and lipid biomarkers have been conflicting. METHODS: We included populations for which NHANES collected complete data. Multivariate logistic regression and subgroup analyses were conducted to ascertain the relationship between blood Pb, Cd, and Se levels and hyperlipidemia. Nonlinear relationships were characterized by smoothed curve fitting and threshold effect analysis. RESULTS: 5429 participants in all, with a mean age of 53.70 ± 16.63 years, were included; 47.1% of the subjects were male, and 3683 (67.8%) of them had hyperlipidemia. After modifying for variables with confounders in a multivariate logistic regression model, we discovered a positive correlation between blood Pb and Se levels and hyperlipidemia (Pb: OR:2.12, 95% CI:1.56-2.88; Se: OR:1.84, 95% CI:1.38-2.45). Gender, age, smoking status, alcohol use status, hypertension, diabetes, and body mass index were not significantly linked with this positive correlation, according to subgroup analysis and interaction test (P for interaction>0.05). Positive correlations between blood Pb, Cd, and Se levels and the risk of hyperlipidemia have been found using smooth curve fitting. CONCLUSIONS: This study demonstrates that higher blood levels of Pb, Cd, and selenium are linked to an increased risk of hyperlipidemia.

Biochemical study of the effect of lead exposure in nonobese gasoline station workers and risk of hyperglycemia: A retrospective case-control study.

Evaluate the relationship between blood lead (Pb) levels and other biomedical markers and the risk of diabetes in gasoline station workers. The participants were separated into 2 groups: group A consisted of 26 workers from gasoline filling stations, while group B comprised 26 healthy individuals. Serum levels of malondialdehyde, IL-1ß, visfatin, insulin, fasting blood sugar, and vitamin D were assessed. Mean Pb level was significantly higher in group A compared to group B (almost 2.9 times higher levels) (14.43 ±â€…1.01 vs 5.01 ±â€…1.41, µg/dL). The levels of visfatin (23.19 ±â€…0.96 vs 3.88 ±â€…0.58, ng/mL), insulin (22.14 ±â€…1.31 vs 11.26 ±â€…0.75, mU/L), fasting blood sugar (118.4 ±â€…26.1 vs 82.7 ±â€…9.2, gm/dL), malondialdehyde (6.40 ±â€…0.27 vs 1.62 ±â€…0.21, nmol/mL), and IL-1ß (330.25 ±â€…10.34 vs 12.35 ± 1.43, pg/mL) were significantly higher in group A, meanwhile; vitamin D (11.99 ±â€…1.55 vs 35.41 ±â€…3.16, ng/mL) were significantly lower in group A. A positive association exists between blood Pb levels and increased inflammatory markers. Lead exposure increases serum insulin and fasting blood sugar, which suggests that it is diabetogenic and that increased inflammation is a possible cause.

Lead Poisoning in a Mother and Her Four Children Using a Traditional Eye Cosmetic - New York City, 2012-2023.

Even low levels of lead in children's blood are associated with developmental delays, difficulty learning, and behavioral issues. Adults are also vulnerable to the detrimental health effects of lead exposure. The New York City (NYC) Department of Health and Mental Hygiene receives blood lead test results for NYC residents and conducts investigations of lead poisoning cases. Blood lead testing of a child aged 4 years in 2012 led to the discovery of blood lead levels above the CDC blood lead reference value of 3.5 µg/dL in the child as well as four other family members over a period of 11 years, including the child's mother and three younger siblings born during 2012-2016. The only potential source of lead exposure identified for all cases was the use of surma, a traditional eye cosmetic, which was found to contain 390,000 ppm lead. The cases in this report highlight the challenges of risk communication when deeply ingrained cultural practices, such as the use of surma, persist despite health warnings. Moreover, they highlight the intergenerational nature of such practices and the need for comprehensive family follow-up once a member is identified as being at risk. These products continue to be available globally, even in places such as the United States where sales are prohibited. Multistakeholder efforts involving local and global engagement could promote reformulation of these products at the countries of origin to eliminate lead as an ingredient.

Exposure to Lead in Drinking Water Causes Cognitive Impairment via an Alzheimer's Disease Gene-Dependent Mechanism in Adult Mice.

Background: Exposure to lead (Pb) is a major public health problem that could occur through contaminated soil, air, food, or water, either during the course of everyday life, or while working in hazardous occupations. Although Pb has long been known as a neurodevelopmental toxicant in children, a recent and growing body of epidemiological research indicates that cumulative, low-level Pb exposure likely drives age-related neurologic dysfunction in adults. Environmental Pb exposure in adulthood has been linked to risk of late-onset Alzheimer's disease (AD) and dementia. Objective: Although the biological mechanism underlying this link is unknown, it has been proposed that Pb exposure may increase the risk of AD via altering the expression of AD-related genes and, possibly, by activating the molecular pathways underlying AD-related pathology. Methods: We investigated Pb exposure using a line of genetically modified mice with AD-causing knock-in mutations in the amyloid precursor protein and presenilin 1 (APPΔNL/ΔNL x PS1P264L/P264L) that had been crossed with Leprdb/db mice to impart vulnerability to vascular pathology. Results: Our data show that although Pb exposure in adult mice impairs cognitive function, this effect is not related to either an increase in amyloid pathology or to changes in the expression of common AD-related genes. Pb exposure also caused a significant increase in blood pressure, a well known effect of Pb. Interestingly, although the increase in blood pressure was unrelated to genotype, only mice that carried AD-related mutations developed cognitive dysfunction, in spite of showing no significant change in cerebrovascular pathology. Conclusions: These results raise the possibility that the increased risk of dementia associated with Pb exposure in adults may be tied to its subsequent interaction with either pre-existing or developing AD-related neuropathology.

Synergistic susceptibility to environmental lead toxicity in chronic kidney disease.

PURPOSE OF REVIEW: While high levels of lead exposure, as occurs accidentally or occupationally, can cause toxicity across multiple organ systems, the hazard of commonly encountered levels of lead in the environment remains unresolved. Challenges to researching the health effects of lead include its complex interplay with renal function, rendering analyses at risk of unaccounted confounding, and the likely small effect size of environmental levels of exposure. While children are known to be disproportionately susceptible to lead toxicity, resulting in appropriately more stringent regulatory surveillance for those under 5 years old, emerging evidence suggests that those with chronic kidney disease (CKD) similarly are at a greater risk. This review summarizes the role of environmental lead toxicity as a potential cause and consequence of CKD. RECENT FINDINGS: Whether environmental lead exposure causes CKD remains debatable, with little recent research advancing the conflicting, mostly cross-sectional, analyses from years ago. However, an emerging body of evidence suggests that CKD increases the susceptibility to lead toxicity. Higher circulating lead levels and lower urinary excretion result in greater lead accumulation in CKD, with simultaneous greater risk of clinically meaningful disease. Recent studies suggest that levels of lead found commonly in the United States drinking water supply, and currently permissible by the Environmental Protection Agency, associate with hematologic toxicity in those with advanced CKD. Whether environmental lead contamination may have additional negative health impact among this at-risk population, including cardiovascular and neurocognitive disease, warrants further study. SUMMARY: The underlying pathophysiology of kidney disease synergizes the susceptibility to environmental lead toxicity for those with CKD. Low levels of exposure, as found commonly in the United States water supply, may have adverse health impact in CKD. Further research will be needed to determine if more stringent environmental regulations are warranted to protect the health of all.

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.

Association between blood lead levels and parathyroid hormone among United States adolescents aged 12-19: a cross-sectional study.

Aims: Studies on the association between serum lead levels and parathyroid function in adolescents are lacking. Therefore, in this study, we elucidated the possible association between blood lead levels (BLLs) and the parathyroid hormone (PTH) in adolescents aged 12-19 years in the United States. Methods: In this study, information from the database of the National Health and Nutrition Examination Survey was utilized. The study included 3919 participants from survey cycles between 2003-2004 and 2005-2006. Multivariable linear regression analysis was performed to determine the correlation between BLLs and PTH. Furthermore, smooth curve fitting was utilized to analyze the dose-response relationship between BLLs and PTH. Results: Multivariable linear regression analysis revealed that every 1 µg/dL increase in BLLs was associated with 0.67 pg/mL increase in PTH (ß = 0.67, 95% CI: 0.16-1.18, p < 0.01). However, sex-stratified subgroup analysis revealed that this positive association was only observed in males (ß = 1.16, 95% CI: 0.50-1.83 p < 0.01). Smooth curve fitting revealed a positive correlation between BLLs and PTH. Conclusions: In adolescents in the United States, BLLs are positively correlated with PTH, particularly in males.

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

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

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

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

Lead in umbilical cord blood and associated factors in Casablanca Morocco: A preliminary results.

BACKGROUND: Lead is the most common toxic metal to which Moroccans are exposed. Given the susceptibility of the fetus to lead, it is crucial to assess prenatal lead exposure. However, in Morocco, no study has assessed prenatal exposure to lead. The main goals of the present study are to determine lead concentration in umbilical cord blood and identify risk factors for prenatal lead exposure in Casablanca, Morocco. METHODS: To achieve these purposes, 87 cord blood lead samples were collected from mothers-baby pairs from January to December 2019. Indeed, a structured questionnaire was used to collect socio-demographic characteristics, obstetric data, leisure, cultural habits, and environmental information. Cord blood lead level was analyzed by inductively coupled plasma-mass spectrometry. RESULTS: The median lead concentration was 4.902 µg/dl with a minimum and maximum of 0.833 µg/dl and 23.593 µg/dl, respectively. A high proportion of the newborns (65.52 %) had cord blood lead levels above the Centers for Disease Control (CDC) allowable threshold limit (3.5 µg/dl). Statistical analysis was performed to assess the association between blood levels and the above factors. Lead levels in cord blood were significantly associated with the maternal educational level, anemia history, delivery mode, passive smoking during pregnancy as well as with the frequency of consumption of tea. CONCLUSION: This study provides the first data on lead levels in newborns. Cord blood lead levels were high in the majority of the participants, these results reinforce the need to establish health surveillance programs in Morocco.

Heavy metal concentrations and clinical symptoms in patients diagnosed with schizophrenia related to cigarette smoking.

In our study, blood concentrations of lead (Pb), arsenic (As), and cadmium (Cd) and urine concentrations of thallium (Tl) were measured together with related symptoms of heavy metal poisoning in cigarette smoking volunteers diagnosed with schizophrenia, in cigarette smokers not diagnosed with schizophrenia, and in the control group of non-smokers and not diagnosed with schizophrenia volunteers. Our study was performed on 171 volunteers divided into the following subgroups: patients diagnosed with schizophrenia with at least 1 year of continuous cigarette smoking experience (56 participants), cigarette smokers not diagnosed with schizophrenia with at least one year of continuous smoking experience (58), and control group (not diagnosed with schizophrenia and non-smoking volunteers) (57). Smoking durations of cigarette smokers diagnosed with schizophrenia and cigarette smokers not diagnosed with schizophrenia are not similar (p = 0.431). Blood Pb, As, and Cd concentrations and urine Tl concentrations were the highest in the subgroup of cigarette smokers not diagnosed with schizophrenia, followed by the subgroup of cigarette smokers diagnosed with schizophrenia, and the control group. Only blood Pb concentrations were significantly higher (probability value p < 0.05) in the group of cigarette smokers not diagnosed with schizophrenia (5.16 µg/dL), comparing to the group of cigarette smokers diagnosed with schizophrenia (3.83 µg/dL) and to the control group (3.43 µg/dL). Blood Cd and As concentrations and urine Tl concentrations were significantly higher (p < 0.05) in cigarette smokers not diagnosed with schizophrenia than in the control group. The results revealed a statistically significant positive correlation (p < 0.001) in the cigarette smokers in the schizophrenia diagnosed group between blood Pb, blood As, and urine Tl concentrations and the duration of cigarette smoking.

Blood Lead Mediates the Relationship between Biological Aging and Hypertension: Based on the NHANES Database.

Hypertension remains a major global public health crisis due to various contributing factors, such as age and environmental exposures. This study delves into exploring the intricate association between biological aging, blood lead levels, and hypertension, along with examining the mediating role of blood lead levels in the relationship between biological aging and hypertension. We analyzed data from two cycles of the NHANES, encompassing 4473 individuals aged 18 years and older. Our findings indicate that biological aging potentially escalates the risk of hypertension and the incidences of systolic blood pressure (SBP) and diastolic blood pressure (DBP) abnormalities. Utilizing weighted quantile sum (WQS) and quantile g-computation (QGC) model analyses, we observed that exposure to heavy metal mixtures, particularly lead, may elevate the likelihood of hypertension, SBP, and DBP abnormalities. Further mediation analysis revealed that lead significantly mediated the relationship between biological aging and hypertension and between biological aging and SBP abnormalities, accounting for 64% (95% CI, 49% to 89%) and 64% (95% CI, 44% to 88%) of the effects, respectively. These outcomes emphasize the criticality of implementing environmental health measures.

Estimating lead-attributable mortality burden by socioeconomic status in the USA.

BACKGROUND: This study aimed to estimate population-level and state-level lead-attributable mortality burdens stratified by socioeconomic status (SES) class in the USA. METHODS: Based on the National Health and Nutrition Examination Survey (NHANES), we constructed individual-level SES scores from income, employment, education and insurance data. We assessed the association between the blood lead levels (BLL) and all-cause mortality by Cox regression in the NHANES cohort (n = 31 311, 4467 deaths). With estimated hazard ratios (HR) and prevalences of medium (2-5 µg/dL) and high (≥ 5 µg/dL) BLL, we computed SES-stratified population-attributable fractions (PAFs) of all-cause mortality from lead exposure across 1999-2019. We additionally conducted a systematic review to estimate the lead-attributable mortality burden at state-level. RESULTS: The HR for every 2-fold increase in the BLL decreased from 1.23 (1.10-1.38) for the lowest SES class to 1.05 (0.90-1.23) for the highest SES class. Across all SES quintiles, medium BLL exhibited a greater mortality burden. Individuals with lower SES had higher lead-attributable burdens, and such disparities haver persisted over the past two decades. In 2017-19, annually 67 000 (32 000-112 000) deaths in the USA were attributable to lead exposure, with 18 000 (2000-41 000) of these deaths occurring in the lowest SES class. Substantial disparities in the state-level mortality burden attributable to lead exposure were also highlighted. CONCLUSIONS: These findings suggested that disparities in lead-attributable mortality burden persisted within US adults, due to heterogeneities in the effect sizes of lead exposure as well as in the BLL among different SES classes.

Evidence of turmeric adulteration with lead chromate across South Asia.

Food adulteration with toxic chemicals is a global public health threat. Lead chromate adulterated spices have been linked with lead poisoning in many countries, from Bangladesh to the United States. This study systematically assessed lead chromate adulteration in turmeric, a spice that is consumed daily across South Asia. Our study focused on four understudied countries that produce >80 % of the world's turmeric and collectively include 1.7 billion people, 22 % of the world's population. Turmeric samples were collected from wholesale and retail bazaars from 23 major cities across India, Pakistan, Sri Lanka, and Nepal between December 2020 and March 2021. Turmeric samples were analyzed for lead and chromium concentrations and maximum child blood lead levels were modeled in regions where samples had detectable lead. A total of 356 turmeric samples were collected, including 180 samples of dried turmeric roots and 176 samples of turmeric powder. In total, 14 % of the samples (n = 51) had detectable lead above 2 µg/g. Turmeric samples with lead levels greater than or equal to 18 µg/g had molar ratios of lead to chromium near 1:1, suggestive of lead chromate adulteration. Turmeric lead levels exceeded 1000 µg/g in Patna (Bihar, India) as well as Karachi and Peshawar (Pakistan), resulting in projected child blood lead levels up to 10 times higher than the CDC's threshold of concern. Given the overwhelmingly elevated lead levels in turmeric from these locations, urgent action is needed to halt the practice of lead chromate addition in the turmeric supply chain.

A sensitive aptasensor mediated by gold nanoparticles/metal organic framework lattice for detection of Pb2+ ion in marine products.

Herein, an enzyme-free fluorescent aptasensor was introduced for the ultrasensitive quantification of lead (Pb2+) ion as a hazardous pollutant of the environment and foodstuffs. A nanocomposite of zeolitic imidazolate frameworks-8 and gold nanoparticles (ZIF-8@AuNPs) was utilized as an efficient quencher of the fluorescence intensity of carboxyfluorescein (FAM) signal reporter. The establishment of a hybrid structure between attached aptamer on ZIF-8@AuNPs nanocomposite, and its FAM-tagged complementary (CP) strand decreased the fluorescence response. The preferential binding between the aptamer and Pb2+ released CP strands, which retrieved the fluorescence signal. The aptasensor could assess Pb2+ in the linear concentration range of 1 pM-1 nM with a detection limit (LOD) of 0.24 pM. Besides, it could quantify Pb2+ in various samples, including fish, shrimp, tap water, milk, and serum samples. The developed aptasensor with the superiorities of easiness, cost-effectiveness, easy-to-operate, and rapidness is promising for controlling marine foodstuff safety.

Determinant Factors of Children's Blood Lead Levels in Java, Indonesia.

INTRODUCTION: Lead poisoning contributes to a significant burden of disease as a toxic substance found in air, soil, and water. In Indonesia, the risk of exposure is high due to the inappropriate recycling of used lead batteries. The objective was to investigate the factors that influence lead levels in children's blood. METHODS: This cross-sectional study assessed blood lead levels (BLLs) in children aged 12-59 months in four communities exposed to used lead-acid batteries (ULABs) recycling activities, comparing them to a control area. The study employed a threshold level of 20 µg/dL to identify high BLLs and utilized a sample size of 324 children from exposed sites and 240 from control sites. Questionnaires, blood lead tests and a home-based assessment for environmental exposures were applied. RESULTS: The study participants comprised 295 boys and 269 girls, with an average age of 35 months. Significant disparities in soil lead concentrations median: Q1-Q3 were found between exposed (6581.7 : 2432.6-16647.1) ppm and control areas (253.5 : 158.8-417.1) ppm. Children in exposed areas had 3.9 times higher odds of BLL ≥20 µg/dL. Fathers with BLL ≥20 µg/dL had children with similarly elevated BLLs. Multivariate analysis identified socioeconomic status, study areas, environmental factors (cookware, food ware, spices, house cleaning), and children's behavior (breastfeeding duration) as determinants of elevated BLLs. Reported environmental factors had notable impact on BLLs, with aluminum cookware (aOR = 1.4, 95%CI [1.2-1.6]), food ware materials (aOR = 1.15, 95%CI [1.0-1.3]), type of spices (aOR = 2.7, 95%CI [1.7-48.0]), and house cleaning method (aOR = 2.9, 95%CI [1.2-7.1]). CONCLUSION: This study highlighted key risk factors affecting children's blood lead levels (BLL) and emphasized the urgency of employing effective strategies to remediate lead-contaminated soils in exposed regions. The findings underscore the need for prompt medical intervention and monitoring for children in these areas, with additional research essential to fully understand lead poisoning pathways in the environment.

Association between mixed metal exposure and stroke risk in Shanxi Province: a case-control study.

BACKGROUND: Stroke is the second leading cause of death for all human beings and poses a serious threat to human health. Environmental exposure to a mixture of metals may be associated with the occurrence and development of stroke, but the evidence in the Chinese population is not yet conclusive. OBJECTIVES: This study evaluated the association between stroke risk and 13 metals METHODS: Metal concentrations in whole blood samples from 100 stroke cases and 100 controls were measured by ICP-MS. The cumulative impact of mixed metal on stroke risk was investigated by using three statistical models, BKMR, WQS and QGC. RESULTS: The case group had higher concentrations of Mg, Mn, Zn, Se, Sn, and Pb than the control group (p<0.05). BKMR model indicated a correlation between the risk of stroke and exposure to mixed metals. WQS model showed that Mg (27.2 %), Se (25.1 %) and Sn (14.8 %) were positively correlated with stroke risk (OR=1.53; 95 %Cl: 1.03-2.37, p=0.013). The QGC model showed that Mg (49.2 %) was positively correlated with stroke risk, while Ti (31.7 %) was negatively correlated with stroke risk. CONCLUSIONS: Mg may be the largest contributor to the cumulative effect of mixed metal exposure on stroke risk, and the interaction between metals requires more attention. These findings could provide scientific basis for effectively preventing stroke by managing metals in the environment.