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The contamination of soil by lead (Pb) is a serious and widespread problem in China, especially in mining areas. This paper summarized the available data regarding Pb-contaminated soils around various metal mines in China. Based on these data, the Pb concentration in the soil and its temporal and spatial changes were analyzed. Potential ecological hazards and adult lead models were also used to estimate ecological and health risks. The results indicated that the concentration of Pb was closely related with the type of mine. Compared with other types of mine, soil around lead-zinc (Pb-Zn) and tin (Sn) mines with high Pb contents in the metallic ores and high pollutant emission coefficient were more strongly polluted by Pb. The characteristic spatial and temporal variations of Pb pollution status in China were clarified, and the results showed that the concentration was high in the southern, southwestern, and central regions of China where many mining areas were located, and the mean value passed a turning point in 2012. Ecological risk assessments indicated that some areas around mines were at considerable to high risk, and the risk was relatively severe in Pb-Zn mining areas. According to the adult lead model, Pb-Zn mines had a greater impact on blood Pb concentration than the other types of mine.

Previous studies have consistently reported an increase in mortality risk, even at low levels of blood lead. The average blood lead concentration in the Korean population has steadily decreased but is still higher than that of developed countries. The purpose of this study was to examine the associations between mortality and blood lead concentrations for adults in Korea. We used the Korea National Health and Nutrition Examination Survey (2008&ndash, 2013) linked Cause of Death data, which are followed by 2018. A total of 7308 subjects who aged over 30 at the baseline examination were included in the analyses. Cox proportional hazard model was used to estimate the hazard ratios of mortality from non-accidental causes and cancer mortality. The estimated hazard ratios (95% CI) for comparison of the second and third tertile group with the lowest tertile group were 2.01 (1.20, 3.40) and 1.91 (1.13, 3.23) for non-accidental mortality and 3.42 (95% CI: 1.65, 7.08) and 2.27 (95% CI: 1.09, 4.70) for cancer mortality, respectively. The dose&ndash, response relationship also showed significant increase in the risk of mortality at blood lead level between 1.5 and 6.0 &mu, g/dL. Our findings suggest that potent policies to lower lead exposure are required for the general Korean population.

To understand the heavy metal pollution in agricultural soils along the East River basin and assess the pollution related health effect to local residents, interviews and archived data were obtained to identify the study sites affected by polluted tailing. Soil samples were collected and tested for heavy metal content and the Comprehensive Pollution Index (CPI). The degree of pollution of agricultural soils in the area was assessed using GIS-based Spatial distribution map of heavy metals and the trend of soil heavy metal risk. Two villages (Matian and Zhudui) near the East River were included in this study for health effect assessment. A total of 193 residents aged 15 or above from each village were tested for the present status of chronic diseases. Convenient sampling method was used to collect blood samples from 78 residents for heavy metal concentration. The contents of Pb, Cd, As, Zn, and Cu in the agricultural soils were all over the standards with a moderate to severe CPI. Among these metals, Cd was the highest followed by Pb, and Cu was the lowest. The contents of Pb, Cd, As, and Zn tend to be higher in soils closer to the river. The prevalence of chronic diseases was over 30%, which is significantly higher than the report from the national central region (23.15%). The average blood lead level (BLL) among children under 14 years is 7.42 &mu, g/dL. Although the adults in Matian village had a significantly higher BLL (&chi, 2 = 8.70, p = 0.03) as compared to Zhudui village, there was no significant difference for the prevalence of chronic diseases between the two villages (&chi, 2 = 3.23, p = 0.09). The mean BLL of children and the proportion of children with BLL &ge, 10 &micro, g/dL in this study are equivalent to the national average. The higher BLL concentration and prevalence of chronic diseases in adults might be due to their long-term exposure to heavy metal contamination environment and higher background level of heavy metals. Findings from this study will form the baseline information for local government to the development of effective approaches to control the heavy metal contamination and reduce the pollution related adverse health effect on local residents.

We measured changes in atmospheric and blood levels of lead and cadmium in the South Korean general population during the past decade. Blood data of 16,873 adults were taken from the Korean National Health and Nutrition Examination Survey (KNHANES, 2008&ndash, 2017). Atmospheric data were taken from 66 air quality monitoring sites in 16 different regions in South Korea. From 2008 to 2017, the geometric mean (GM) blood lead level decreased from 2.37 to 1.46 &mu, g/dL (38.4% decrease), and the atmospheric lead concentration decreased by 61.0% in the overall population. During this time, the GM blood cadmium level decreased from 0.88 to 0.72 &mu, g/L (18.2% decrease), and the atmospheric cadmium concentration decreased by 63.6%. Multiple linear regression analysis indicated that a half reduction in air lead was associated with a 0.09 &mu, g/dL decrease in blood lead (95% CI: 0.03 to 0.15) in a subgroup of the metropolitan city population. However, a half reduction in air cadmium had no significant effect on blood cadmium. Multiple linear regression analyses indicated that the decrease in blood lead level over 10 years in Korea was related to the decrease in atmospheric lead concentration. However, the decrease in blood cadmium level during this time was not significantly associated with the decrease in atmospheric cadmium concentration. Our findings suggest that inhalation is a major source of lead exposure, but not of cadmium exposure. Ingestion of dietary cadmium presumably has a stronger impact on blood cadmium levels.

Objective: To determine blood lead levels (BLL) in a healthy paediatric population and to analyse related sociodemographic, dietary and haematological factors. Methods: A cross-sectional study was made of 1427 healthy subjects aged 1–16 years from the city of Almería (south-eastern Spain). BLL, iron parameters and erythropoietin were determined, and sociodemographic and dietary data obtained. The study paramateters was analyses in BLL toxic and BLL no toxic group by multiple logistic regression. Results: The mean BLL was 1.98 ± 1.1 µg/dL (95% CI:1.91–2.04). For 5.7% of the population, mean BLL was 2–5 µg/dL, for 2.1% it was &gt, 5 µg/dL and for 0.15% it was &gt, 10 µg/dL. Multivariate analysis showed that immigrant origin (OR:11.9, p &lt, 0.0001), low level of parental education (OR:4.6, 0.02) and low dietary iron bioavailability (OR: 3.2, 0.02) were all risk factors for toxic BLL. Subjects with toxic and non-toxic BLL presented similar iron and erythropoiesis-related parameters, except erythrocyte protoporphyrin, which was significantly higher in the BLL &gt, 5 µg/dL group. Conclusions: BLL and the prevalence of toxic BLL in healthy subjects aged 1–16 years living in south-eastern Spain are low and similar to those found in other developed countries. The factors associated with toxic BLL are immigrant origin, low level of parental education and dietary iron deficiency. The toxicity of BLL was not related to changes in the analytical parameters studied.

Background: Lead inhibits the enzymes in heme biosynthesis, mainly reducing &delta, aminolevulinic acid dehydratase (ALAD) activity, which could be an available biomarker. The aim of this study was to detect the threshold of &delta, aminolevulinic acid dehydratase activity reduced by lead exposure. Methods: We collected data on 121 lead workers and 117 non-exposed workers when annual health examinations were performed. ALAD activity was determined by the standardized method of the European Community. ALAD G177C (rs1800435) genotyping was conducted using the polymerase chain reaction and restricted fragment length polymorphism (PCR-RFLP) method. In order to find a threshold effect, we used generalized additive models (GAMs) and scatter plots with smoothing curves, in addition to multiple regression methods. Results: There were 229 ALAD1-1 homozygotes and 9 ALAD1-2 heterozygotes identified, and no ALAD2-2 homozygotes. Lead workers had significantly lower ALAD activity than non-exposed workers (41.6 &plusmn, 22.1 vs. 63.3 &plusmn, 14.0 U/L, p &lt, 0.001). The results of multiple regressions showed that the blood lead level (BLL) was an important factor inversely associated with ALAD activity. The possible threshold of BLL affecting ALAD activity was around 5 &mu, g/dL. Conclusions: ALAD activity was inhibited by blood lead at a possible threshold of 5 &mu, g/dL, which suggests that ALAD activity could be used as an indicator for lead exposure regulation.

The negative effect of lead exposure on children&rsquo, s intelligence is well-documented. Less is known about the impact of lead on the use of executive functions to self-regulate behavior. We measured blood lead level (BLL) in a sample of first grade children from Montevideo, Uruguay (n = 206, age 6.7 &plusmn, 0.5 years, 59.7% boys). Behavior was assessed with teacher versions of the Conners Rating Scale (CRS) and the Behavior Rating Inventory of Executive Functions (BRIEF). Mean BLL was 4.2 &plusmn, 2.1 &mu, g/dL, 10% had mild-to-severe ratings of Attentional Deficit with Hyperactivity Disorder (ADHD) (T score &gt, 65). In negative binomial regression, BLL was not associated with CRS sub-scales, but was associated with a poorer ability to inhibit inappropriate behaviors, prevalence ratio (PR) [95% CI]: 1.01 [1.00, 1.03] as measured by the BRIEF. In covariate-adjusted models, the association with BLL was attenuated. When stratified by sex, the covariate-adjusted association between BLL, hyperactivity, poorer inhitibion, emotional control, and behavioral regulation was marginally significant for girls but not boys. In summary, among children with low lead-exposure, we found some, but nonetheless modest, evidence of a relationship between higher BLL and child behavior. If confirmed by larger studies and other objective measures of behavior, such links could have implications for learning and social interaction, particularly among girls.

Objective: The purpose of this study was to explore the full distribution of children&rsquo, s lead poisoning and identify &ldquo, high risk&rdquo, locations or areas in the neighborhood of the inner city of Syracuse (NY, USA), using quantile regression models. Methods: Global quantile regression (QR) and geographically weighted quantile regression (GWQR) were applied to model the relationships between children&rsquo, s lead poisoning and three environmental factors at different quantiles (25th, 50th, 75th, and 90th). The response variable was the incident rate of children&rsquo, s blood lead level &ge, 5 &micro, g/dL in each census block, and the three predictor variables included building year, town taxable values, and soil lead concentration. Results: At each quantile, the regression coefficients of both global QR and GWQR models were (1) negative for both building year and town taxable values, indicating that the incident rate of children lead poisoning reduced with newer buildings and/or higher taxable values of the houses, and (2) positive for the soil lead concentration, implying that higher soil lead concentration around the house may cause higher risks of children&rsquo, s lead poisoning. Further, these negative or positive relationships between children&rsquo, s lead poisoning and three environmental factors became stronger for larger quantiles (i.e., higher risks). Conclusions: The GWQR models enabled us to explore the full distribution of children&rsquo, locations or areas in the neighborhood of the inner city of Syracuse, which would provide useful information to assist the government agencies to make better decisions on where and what the lead hazard treatment should focus on.

We aimed to examine the associations between blood lead and mercury levels and individual and community level socioeconomic positions (SEPs) in school-aged children. A longitudinal cohort study was performed in 33 elementary schools in 10 cities in Korea. Among a total of 6094 children included at baseline, the final study population, 2281 children followed-up biennially, were analyzed. The geometric mean (GM) levels of blood lead were 1.73 μg/dL (range 0.02–9.26) and 1.56 μg/dL (range 0.02–6.83) for male and female children, respectively. The blood lead levels were significantly higher in males, children living in rural areas, and those with lower individual SEP. The GM levels of blood mercury were 2.07 μg/L (range 0.09–12.67) and 2.06 μg/L (range 0.03–11.74) for males and females, respectively. Increased blood mercury levels were significantly associated with urban areas, higher individual SEP, and more deprived communities. The risk of high blood lead level was significantly higher for the lower individual SEP (odds ratio (OR) 2.18, 95% confidence interval (CI) 1.36–3.50 in the lowest educational attainment of the father), with a significant dose-response relationship observed after adjusting for the community SEP. The association between high blood lead levels and lower individual SEP was much stronger in the more deprived communities (OR 2.88, 95% CI 1.27–6.53) than in the less deprived communities (OR 1.40, 95% CI 0.76–2.59), and showed a significant decreasing trend during the follow-up only in the less deprived communities. The risk of high blood mercury levels was higher in higher individual SEP (OR 0.64, 95% CI 0.40–1.03 in the lowest educational attainment of the father), with a significant dose-response relationship noted. Significant decreasing trends were observed during the follow-up both in the less and more deprived communities. From a public health point-of-view, community level intervention with different approaches for different metals is warranted to protect children from environmental exposure.

Mount Isa, Queensland, is one of three Australian cities with significant lead emissions due to nonferrous mining and smelting. Unlike the two other cities with lead mines or smelters, Mount Isa currently has no system of annual, systematic, community-wide blood lead level testing; and testing rates among Indigenous children are low. In previous screenings, this group of children has been shown to have higher average blood lead levels than non-Indigenous children. The first aim of this study was to assess whether parents and children would participate in less invasive, rapid point-of-care capillary testing. The second aim was to measure blood lead levels among a range of children that roughly reflected the percentage of the Indigenous/non-Indigenous population. This pilot study is based on a convenience sample of children between the ages of 12 and 83 months who were recruited to participate by staff at a Children and Family Centre. Over three half-days, 30 children were tested using capillary blood samples and the LeadCare II Point-of-Care testing system. Rapid point-of-care capillary testing was well tolerated by the children. Of 30 children tested, 40% (n = 12) had blood lead levels ≥5 µg/dL and 10% had levels ≥10 µg/dL. The highest blood lead level measured was 17.3 µg/dL. The percentage of children with blood lead levels ≥5 µg/dL was higher among Indigenous children compared to non-Indigenous (64.2% compared to 18.8%) as was the geometric mean level (6.5 (95% CI, 4.7, 9.2) versus 2.4 (95% CI, 1.8, 3.1)), a statistically significant difference. Though based on a small convenience sample, this study identified 12 children (40%) of the sample with blood lead levels ≥5 µg/dL. Due to historical and ongoing heavy metal emissions from mining and smelting in Mount Isa, we recommend a multi-component program of universal blood lead level testing, culturally appropriate follow-up and intervention for children who are identified with blood lead levels ≥5 µg/dL. We further recommend focused outreach and assistance to the Indigenous community, and further control of emissions and remediation of existing environmental lead contamination in children’s play and residential areas.

Research has shown that long-term exposure to lead harms the hematological system. The homeostatic iron regulator HFE (hemochromatosis) mutation, which has been shown to affect iron absorption and iron overload, is hypothesized to be related to lead intoxication in vulnerable individuals. The aim of our study was to investigate whether the HFE genotype modifies the blood lead levels that affect the distributions of serum iron and other red blood cell indices. Overall, 121 lead workers and 117 unexposed age-matched subjects were recruited for the study. The collected data included the blood lead levels, complete blood count, serum iron, total iron binding capacity, transferrin, and ferritin, which were measured during regular physical examinations. All subjects filled out questionnaires that included demographic information, medical history, and alcohol and tobacco consumption. HFE genotyping for C282Y and H63D was determined using polymerase chain reaction and restriction fragment length polymorphism (PCR/RFLP). The mean blood lead level in lead workers was 19.75 &micro, g/dL and was 2.86 &micro, g/dL in unexposed subjects. Of 238 subjects, 221 (92.9%) subjects were wild-type (CCHH) for HFE C282Y and H63D, and 17 (7.1%) subjects were heterozygous for a H63D mutation (CCHD). Multiple linear regression analysis showed that blood lead was significantly negatively associated with hemoglobin (Hb), mean corpuscular hemoglobin concentration (MCHC), and mean corpuscular volume (MCV), whereas the HFE variant was associated negatively with MCV and positively with ferritin. An interactive influence on MCV was identified between blood lead and HFE variants. Our research found a significant modifying effect of the HFE variant, which possibly affected MCV. The HFE H63D heterozygous (CCHD) variant seemed to provide a protective factor against lead toxicity. Future studies should focus on competing binding proteins between iron and lead influenced by gene variation.

Lead (Pb) is one of the major contaminants in many industries, and imposes hazardous effects on multiple human organs and systems. Studies have shown that lead is able to induce the alteration of microRNA (miRNA) expression in serum and organs. In this study we investigated whether polymorphisms in miRNA-regulating genes were associated with the risk of lead exposure. We genotyped seven single-nucleotide polymorphisms (SNPs) in 113 lead-sensitive and 113 lead-resistant lead-related Chinese workers by Taqman analysis. The lead-sensitive group showed a significantly higher blood lead level (BLL) than the resistant group based on unconditional logistic regression results. One SNP in XPO5 extron (rs2257082) was significantly associated with lead-poisoning (p = 0.022, odds rate (OR) = 1.63, 95% confidence interval (CI) = 1.07–2.47 in the C allele compared to the T allele). There were no significant associations between the other six SNPs and the blood lead levels. Therefore, polymorphism rs2257082 could be used to distinguish lead-resistant and lead-susceptible populations, and to develop more specific and accurate preventions.

Lead pollution incidents have occurred frequently in mainland China, which has caused many lead poisoning incidents. This paper took a battery recycling factory as the subject, and focused on measuring the blood lead levels of environmental samples and all the children living around the factory, and analyzed the relationship between them. We collected blood samples from the surrounding residential area, as well as soil, water, vegetables. The atomic absorption method was applied to measure the lead content in these samples. The basic information of the generation procedure, operation type, habit and personal protect equipment was collected by an occupational hygiene investigation. Blood lead levels in 43.12% of the subjects exceeded 100 μg/L. The 50th and the 95th percentiles were 89 μg/L and 232 μg/L for blood lead levels in children, respectively, and the geometric mean was 94 μg/L. Children were stratified into groups by age, gender, parents’ occupation, distance and direction from the recycling plant. The difference of blood lead levels between groups was significant (p < 0.05). Four risk factors for elevated blood lead levels were found by logistic regression analysis, including younger age, male, shorter distance from the recycling plant, and parents with at least one working in the recycling plant. The rate of excess lead concentration in water was 6.25%, 6.06% in soil and 44.44% in leaf vegetables, which were all higher than the Chinese environment standards. The shorter the distance to the factory, the higher the value of BLL and lead levels in vegetable and environment samples. The lead level in the environmental samples was higher downwind of the recycling plant.

Attention deficit/hyperactivity disorder (ADHD) is one of the most common childhood neurobehavioral conditions. Evidence of the negative effects of sugar-sweetened beverages (SSBs) on mental health has not been convincing, although a few studies have found an association between high SSB levels and attention problems in children. This study aimed to test the hypothesis that SSB consumption is associated with ADHD among children. Doctor-diagnosed ADHD cases (n = 173) and non-ADHD controls (n = 159) between age 4 to 15 were recruited. SSB consumption, socio-demographic and lifestyle characteristics of the children, as well as of their mothers’ characteristics during pregnancy, were collected using a questionnaire. Blood lead levels and polymorphisms of two commonly verified dopaminergic-related genes (the D4 dopamine receptor gene DRD4 and the dopamine transporter gene DAT1) were also analyzed. There was a dose-response relationship between SSB consumption and ADHD. After covariates were adjusted, children who consumed SSBs at moderate levels and high levels had 1.36 and 3.69 odds, respectively, of having ADHD, compared with those who did not consume SSBs (p for trend < 0.05). Similar results were obtained when females were excluded. Our findings highlighted the adverse correlation between SSB consumption and ADHD and indicated a dose-response effect even after covariates were adjusted.

In Flint; MI; USA; a public health crisis resulted from the switching of the water supply from Lake Huron to a more corrosive source from the Flint River in April 2014; which caused lead to leach from water lines. Between 2010 and 2015; Flint area children’s average blood lead patterns display consistent peaks in the third quarter of the year. The third quarter blood lead peaks displayed a declining trend between 2010 and 2013; then rose abruptly between the third quarters of 2013 from 3.6% blood lead levels ≥5 µg/dL to a peak of about 7% in the third quarter of 2014; an increase of approximately 50%. The percentage of blood lead level ≥5 µg/dL in the first quarter of 2015 then dropped to 2.3%; which was the same percentage as the first quarter of 2014 (prior to the Flint River water source change). The Flint quarterly blood lead level peak then rose to about 6% blood lead levels ≥ 5 µg/dL in the third quarter of 2015; and then declined to about 2.5% in the fourth quarter of 2015. Soil lead data collected by Edible Flint food collaborative reveal generally higher soil lead values in the metropolitan center for Flint; with lower values in the outskirts of the city. The questions that are not being asked is why did children’s blood lead levels display a seasonal blood lead pattern before the introduction of the new water supply in Flint; and what are the implications of these seasonal blood lead patterns? Based upon previous findings in Detroit and other North American cities we infer that resuspension to the air of lead in the form of dust from lead contaminated soils in Flint appears to be a persistent contribution to lead exposure of Flint children even before the change in the water supply from Lake Huron to the Flint River.

This study is to determine the distribution of the delta-aminolevulinic acid dehydratase (ALAD) polymorphism among Han subjects of the Chinese population and to study whether the polymorphism in the ALAD gene modifies the toxicity of lead in lead-exposed workers. For this purpose we conducted a cross-sectional study on 156 Chinese workers who were exposed to lead in lead-acid battery and electric-flex manufacturing plants. The authors found that the allele frequencies of ALAD1 and ALAD2 were 0.9679 and 0.0321, respectively. Workers with the ALAD 1-1 genotype were associated with higher blood lead levels than those with the ALAD 1-2 genotype. Blood and urine lead levels were much higher in storage battery workers than in cable workers. The self-conscious symptom survey showed that the incidences of debilitation, amnesia and dreaminess were much higher in those had more than five years of tenure or contact with lead on the job within the ALAD 1-1 genotype subgroup. Laboratory examinations showed that serum iron and zinc levels in workers’ with the ALAD 1-2 genotype were higher than those with the ALAD 1-1 genotype, especially in storage-battery workers. Correlation analysis indicated that the blood lead level negatively correlated with serum calcium, iron and zinc level. The data of this study suggest that the ALAD gene polymorphism and serum ion levels may modify the kinetics of lead in blood. Therefore, the authors recommend that an adequate intake of dietary calcium, iron, and zinc or the calcium, iron, and zinc supplementation should be prescribed to Chinese lead exposed workers.

Cardiovascular-related clinical markers were evaluated in this cross-sectional study of United States adults (aged ≥ 20) exposed to lead via the National Health and Nutrition Examination Survey 2007–2008 and the 2009–2010 datasets. In four quartiles of exposure—0–2 μg/dL, 2–5 μg/dL, 5–10 μg/dL, and 10 μg/dL and over, clinical and anthropometric markers were evaluated—to examine how the markers manifested in the quartiles. Associations were determined via linear regression. Finally, clinical makers, and how they manifested between exposed and less-exposed occupations, were explored in addition to how duration of exposure altered these clinical markers. In regression analysis, Diastolic Blood Pressure (DBP) and high-density lipoprotein (HDL) cholesterol, were significantly associated with blood lead level (BLL). In the occupational analysis, Systolic Blood Pressure (SBP), DBP, C-reactive protein (CRP), triglycerides, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, showed differences between populations in the exposed and less-exposed occupations. Regarding Agriculture, Forestry & Fishing, the duration of exposure altered SBP, CRP, and LDL cholesterol. With mining, the duration of exposure altered SBP, DBP, triglycerides, and HDL cholesterol, whereas in construction, the duration in occupation altered SBP, triglycerides, and CRP. In conclusion, lead exposure has a profound effect on the cardiovascular system, with potentially adverse outcomes existing at all exposure levels.

This cross-sectional study investigated the relationship between the aminolevulinate dehydrogenase (ALAD) genotype and blood lead levels among 101 Japanese workers. Blood lead concentration measurement, biomarkers, and genotyping were performed. The minor allele frequency (MAF) for ALAD (ALAD2) was 0.08. Although the blood lead level in the subjects with heterozygous GC genotype was significantly higher than those with homozygous GG genotype, there were no significant differences for hemoglobin, hematocrit, serum and urinary ALA levels among genotypes. ALAD2 genotype was significantly associated with the blood lead concentration, even in the environmental lead exposed subjects. Further confirmation with a large sample size is needed.