Occupational lead exposure aboard a tall ship.

Lead poisoning is an emerging worldwide public health concern, especially in the developing countries. Occupational tasks such as spray painting and welding in informal automobile repair enterprises present risks of exposures to lead generally through inhalation and ingestion. The artisans therefore risk high blood lead (BPb) levels, which is critical to chronic adverse health effects of lead. The study aimed at assessing the influence of occupational tasks on personal airborne lead exposures and to evaluate the association between these exposures with blood lead (BPb) levels among the artisans. A cross-sectional study was conducted in ten informal automobile repair workshops. Task-specific personal inhalable air samples and blood samples were collected concurrently for 20 participants performing five distinct occupational tasks. Lead levels were analysed using inductively coupled plasma atomic emission spectroscopy and data analysed by analysis of variance, simple and multiple linear regressions. The results indicated significant differences in airborne lead (PbA) exposure levels in different occupational tasks (p = 0.000). Lead-acid battery repairs recorded mean PbA exposure level of [76.11 ± (10.81 SE) µg/m3] exceeding the WHO 50µg/m3 airborne lead permissible exposure limit. The average (PbA) exposure level was 22.55 ± (5.05 SE) µg/m3, while the mean (BPb) level was 25.08 ± (3.48 SE) µg/dl. A significant positive correlation between task-based airborne lead with blood lead levels was observed (r = 0.68, p = 0.001). In conclusion, the occupational tasks influenced personal airborne lead exposure levels, which in turn was an important predictor of blood lead levels. The study recommends lead exposure assessments, medical screening and intervention measures to minimize the risk and consequences of occupational exposures to lead among the study population.

Childhood lead exposure remains a key health concern for officials worldwide, contributing some 600,000 new cases of intellectually disabled children annually. Most children affected by high exposure to lead live in low- and middle-income countries. The leaded gasoline phase out in India was completed in 2000. Yet, in 2020, an estimated 275 million children aged 0 to 9 years had blood lead levels (BLLs) ≥ 5 μg/dL known to adversely affect intelligence and behavior. Lead sources reported in India include spices, cookware, paint, traditional medicines and cosmetics, and lead-acid battery recycling and repair. However, their relative contribution has not been characterized. More than 200 lead pollution sites related to battery recycling and repair activities were identified in Bihar and Jharkhand, India. Ninety percent of the recycling sites had soil lead concentrations exceeding the US Environmental Protection Agency’s standards. We compared blood and environmental lead levels in two groups of children in Patna, Bihar. Households in proximity to battery recycling operations (Proximal n = 67) versus households distal to these operations (Distal n = 68). The average age of children was 40 months; 46% were female. Overall, the geometric mean (GM) BLL was 11.6 μg/dL. GM BLLs of children in Proximal and Distal households were not significantly different (10.2 μg/dL vs. 13.1 μg/dL respectively; p≤0.07). About 87% children, 56 Proximal and 62 Distal had BLLs ≥5 μg/dl. Lead concentrations in environmental samples were significantly higher in Proximal households (soil mean 9.8 vs. 1.6 μg/ft2; dust mean 52.9 vs. 29.9 μg/ft2 p<0.001; Proximal vs. Distal respectively) whereas concentrations in all spices were higher in Distal households (mean 46.8 vs 134.5 ppm p<0.001; Proximal vs. Distal respectively), and turmeric (mean 59.4 vs. 216.9 ppm Proximal vs. Distal respectively). In multivariate analyses for all children lead in spices and turmeric and number of rooms in the house were significant while for the Proximal group only lead in spices remained in the model. The predictive value of these models was poor. For the Distal group, a model with lead concentration in spices, turmeric and soil and number of rooms in the house was a much better fit. Of the 34 water samples collected, 7 were above the Indian standard of 10 ppb for lead in drinking water (2 in the Proximal area, 5 in the Distal area). Children in Patna, Bihar, India are exposed to multiple sources of lead, with lead levels in house dust and loose, locally sourced spices the most likely to increase blood lead levels. A holistic approach to blood lead testing and source identification and remediation are necessary to prevent lead exposure.

To determine the risk of increased blood lead levels in children with aural, nasal, or gastrointestinal foreign bodies, the authors prospectively obtained venous blood lead and erythrocyte protoporphyrin levels from 40 study patients and two control groups without foreign bodies (65 patients presenting to a medical clinic and 40 patients presenting to an emergency department). A questionnaire was used to assess environmental and behavioral risk factors for lead poisoning in the three groups. Mean blood lead level was higher in children with foreign bodies (P less than .001), and they were more likely to have a venous blood lead value of more than 1.2 mumol/L (25 micrograms/dL, P less than .01) than patients in either control group. Seventy-eight percent of study patients had no prior lead screening by parent's report vs 64% of emergency department control subjects and 55% of medical clinic control subjects. Control patients in the emergency department had the same incidence of elevated blood lead values as patients enrolled from the medical clinic (6%). No differences in environmental risk factors were found among the three groups. Study patients more often had a history of pica or ingestion of a poison than control patients from the medical clinic. Inner-city children with foreign bodies have increased lead exposure and may have an increased risk for lead poisoning. In areas of high prevalence of lead poisoning, children with foreign bodies should be screened for lead poisoning in the emergency department. General lead screening in the emergency department may be justified for high-risk, inner-city populations.

ObjectivesHomocysteine has been causally associated with various adverse health outcomes. Evidence supporting the relationship between lead and homocysteine levels has been accumulating, but most prior studies have not focused on...

Background: Anemia is a major health problem in infants and children in developing countries such as Indonesia. The problem is often related to the declined levels of some micronutrients in the body such as iron, zinc, and copper. It may be also associated with increased absorption of heavy metals such as lead. According to MOH, in 2013 the prevalence of anemia in children aged 5-14 years was 26.4%. This study aimed to determine the correlation between lead level, socio-demographic factors, nutritional status, nutrition intake, and hemoglobin level in elementary students in, Bogor, West Java. Subjects and Method: This was an analytic observational study with a cross-sectional design. The study was conducted in four elementary schools in Cinangka, Bogor city, West Java, from May to June 2014. A sample of 103 elementary school students grade 4 to 6 was selected for this study by random sampling. The dependent variable was hemoglobin level. The independent variables were protein intake, iron intake, calcium intake, blood lead level, nutritional status, education, and parental income. Blood specimen was taken tomeasure blood lead and hemoglobin levels. Nutritional status was measured in body mass index converted to Z-score. Other variables were collected by questionnaire. The data were analyzed by a multiple logistic regression.Results: Multiple logistic regression showed that hemoglobin level increased with protein intake (OR= 4.18; 95% CI= 1.06 to 16.49; p= 0.030) and iron intake (OR= 5.40; 95% CI= 1.41 to 20.72; p= 0.008). Blood lead level, nutritional status, education, parental income, and calcium intake did not show significant association with hemoglobin level.Conclusion: Hemoglobin level increases with protein intake and iron intake. Keywords: hemoglobin level, lead level, iron intake, protein intake

Background Thyroid stimulating hormones (TSH) are associated with metabolic syndrome (MetS) and share a common pathway with lead in the causation of MetS. Many studies have reported the association of lead exposure and MetS but no study considered the possibility of TSHs working as an intermediate factor in between those two variables. In this study, we examined the role of TSHs as a partial mediator between lead and MetS. Methods A sample of 1,688 adults (≥19 years of age) who participated in the Korea National Health and Nutrition Examination Survey in 2013 was analysed. After adjusting for various demographic and clinical parameters thought of as confounders, the associations between blood lead levels, serum TSH levels and MetS were determined by odds ratios (ORs) obtained from multiple logistic regression models. Results In this study, the prevalence of MetS in the Korean population was 21.9% and the geometric mean of blood lead and serum TSH levels were 1.96 μg/dL and 2.17 µIU/mL respectively. Blood lead was positively associated with high TSH levels (upper 25%) with an OR (95% Confidence Interval (CI)) of 1.79 (1.24, 2.58) per doubling of lead. The increase of blood lead and serum TSH levels both positively increased the odds for the prevalence of MetS. The OR of MetS per doubling of blood lead was 1.53 (1.00, 2.35) and further adjustment for TSHs did not significantly attenuate the OR [1.52 (0.98, 2.34)]. Conclusions These findings suggest that higher levels of blood lead are associated with elevated serum TSH levels and higher risks of MetS. Moreover, by exploring the role of TSH as a partial mediator in the association between lead and MetS, we verified that TSH does not mediate the effect of lead on MetS, therefore confirming that lead has an independent effect on causing MetS.

Blood and faecal lead levels in children with various functional gastrointestinal disorders

Tinnitus is a common symptom among adults in the United States. Increasing evidence indicates that prolonged exposure to heavy metals and excessive intake of trace elements from environmental pollution can increase the likelihood of hearing loss. Although studies have reported associations between heavy metals and hearing loss, the relationship between heavy metals and tinnitus remains uninvestigated. After accounting for the complex survey design, we assessed cross-sectional data on blood lead, cadmium, mercury, selenium, and manganese levels in 4950 participants from the National Health and Nutrition Examination Survey database (2012–2018). We used weighted multivariate logistic regression, weighted multivariate linear regression, restricted cubic spline regression, and receiver operating characteristic curve analysis to investigate the relationship between these 5 blood heavy metals and tinnitus. Subgroup and sensitivity analyses were performed to evaluate consistency across subgroups and the robustness of the findings. Compared with the lowest quartile (Q1), the odds of tinnitus were significantly higher in the highest quartiles of blood lead (odds ratio = 1.63, 95% CI: 1.23–2.16) and cadmium (odds ratio = 1.32, 95% CI: 1.02–1.70). Restricted cubic spline curves indicated a nonlinear association between the odds of tinnitus and blood lead, cadmium, mercury, and selenium levels. However, no nonlinear relationship was found regarding blood manganese levels (P for nonlinear = .1334; P total = .2446). Subgroup analyses suggested that sex and ethnicity may modify the strength of the association between blood cadmium and blood lead levels with tinnitus prevalence. The association between blood mercury levels and tinnitus was highly homogeneous and stable across all examined demographic and clinical subgroups. The link between blood selenium levels and tinnitus was more pronounced among males, non-Hispanic whites, and individuals aged 40 to 60 years. Blood lead, cadmium, mercury, and selenium levels were significantly associated with the prevalence of tinnitus. High levels of these metals may be potential indicators for tinnitus management.

Childhood lead poisoning in China: challenges and opportunities.

A cross-sectional study was performed to evaluate the influence of polymorphisms in the [delta]-aminolevulinic acid dehydratase (ALAD) and vitamin D receptor (VDR) genes on blood lead, tibia lead, and dimercaptosuccinic acid (DMSA)-chelatable lead levels in 798 lead workers and 135 controls without occupational lead exposure in the Republic of Korea. Tibia lead was assessed with a 30-min measurement by (109)Cd-induced K-shell X-ray fluorescence, and DMSA-chelatable lead was estimated as 4-hr urinary lead excretion after oral administration of 10 mg/kg DMSA. The primary goals of the analysis were to examine blood lead, tibia lead, and DMSA-chelatable lead levels by ALAD and VDR genotypes, controlling for covariates; and to evaluate whether ALAD and VDR genotype modified relations among the different lead biomarkers. There was a wide range of blood lead (4-86 microg/dL), tibia lead (-7-338 microg Pb/g bone mineral), and DMSA-chelatable lead (4.8-2,103 microg) levels among lead workers. Among lead workers, 9.9% (n = 79) were heterozygous for the ALAD(2) allele and there were no homozygotes. For VDR, 10.7% (n = 85) had the Bb genotype, and 0.5% (n = 4) had the BB genotype. Although the ALAD and VDR genes are located on different chromosomes, lead workers homozygous for the ALAD(1) allele were much less likely to have the VDR bb genotype (crude odds ratio = 0.29, 95% exact confidence interval = 0.06-0.91). In adjusted analyses, subjects with the ALAD(2) allele had higher blood lead levels (on average, 2.9 microg/dL, p = 0.07) but no difference in tibia lead levels compared with subjects without the allele. In adjusted analyses, lead workers with the VDR B allele had significantly (p < 0.05) higher blood lead levels (on average, 4.2 microg/dL), chelatable lead levels (on average, 37.3 microg), and tibia lead levels (on average, 6.4 microg/g) than did workers with the VDR bb genotype. The current data confirm past observations that the ALAD gene modifies the toxicokinetics of lead and also provides new evidence that the VDR gene does so as well.

EXAMINING THE ASSOCIATION BETWEEN MANGANESE AND LEAD BLOOD LEVELS IN SCHOOLCHILDREN IN FOUR SELECTED REGIONS OF SOUTH AFRICA

Back to table of contents Previous article Next article Clinical & Research NewsFull AccessLead in Children's Blood May Contribute to ADHD's Hyperactivity ComponentJoan Arehart-TreichelJoan Arehart-TreichelSearch for more papers by this authorPublished Online:2 Nov 2007https://doi.org/10.1176/pn.42.21.0020aThanks to government regulation, lead poisoning in children is no longer common in the United States. However, American youngsters are still widely exposed to low levels of lead in water, soil, and other venues.But even these lower levels of lead in turn may contribute to attention-deficit/hyperactivity disorder (ADHD) in some American children, a new study suggests.The study was headed by Joel Nigg, Ph.D., a professor of clinical psychology at Michigan State University. Results are in press with Biological Psychiatry.Studies done in the 1980s have already linked the amount of lead in children's blood with ADHD. But the levels—10-20 ug/dl—were higher than the levels usually found in American children today, which average 1-2 ug/dl. So Nigg and his colleagues wanted to see whether these lower blood levels could also be associated with ADHD.The researchers recruited subjects for the study from schools, clinics, and advertisements. To obtain the broadest and most representative sample possible, the investigators advertised for both healthy children and children suspected of having or diagnosed with ADHD. A total of 845 families expressed interest in participating in the study.The children in these families were then screened extensively with various instruments—say, the Child Behavior Checklist and the Kiddie Schedule for Affective Disorders and Schizophrenia—to determine whether they had ADHD or other psychiatric disorders.One hundred-and-fifty children aged 8 to 17 were finally selected to participate in the study. A third had ADHD, combined type; a third had ADHD, predominantly inattentive type; and the remainder did not have ADHD and could thus serve as controls. Moreover, the levels of lead in the blood of all the subjects closely matched the American average of 1-2 ug/dl, with a maximum level of 3.4 ug/dl.Blood lead levels were significantly higher in the children with ADHD, combined type, than in the control children, but this was not the case in children who had ADHD, predominantly inattentive type. So Nigg and his group believe that low lead levels in the blood might play a role in the hyperactivity component of ADHD, but not in the inattention component of it.How lead might contribute to hyperactivity is not clear. It does not seem to be mediated by lead's negative impact on intelligence, because while the researchers found that blood lead levels in their subjects were correlated with IQ, they also found that IQ could not explain the link between lead and hyperactivity. Low-level lead exposure is known to disrupt mid-brain dopamine circuitry, and this circuitry, however, is involved in ADHD.Although the researchers suspect that low blood levels of lead may play a role in a number of cases of ADHD-related hyperactivity, they do not believe that this is so in all cases, because some of their subjects with mildly elevated blood levels did not have ADHD-related hyperactivity, while some of their subjects with ADHD-related hyperactivity did not have elevated blood levels of lead.The study's results have public health policy implications, Nigg told Psychiatric News, emphasizing that “prevention of lead exposure may be important at even lower levels than we thought.”The study was financed by Michigan State University and the Centers for Disease Control and Prevention.An abstract of “Low Blood Lead Levels Associated With Clinically Diagnosed Attention-Deficit/Hyperactivity Disorder and Mediated by Weak Cognitive Control” is posted at<www.journals.elsevierhealth.com//periodicals/bps> under “Articles in Press.” ▪ ISSUES NewArchived

Back ground and objective Pruritus is a common and often distressing symptom in patients with chronic kidney disease. Though the pathogenesis of uremic pruritus remains poorly understood, however systemic inflammation is one of the possible pathogenesis of uremic pruritus, and blood lead level has been noted to be associated with inflammation and nutritional status in long-term hemodialysis patients. There might be an interaction or association, therefore, between blood lead level and uremic pruritus through systemic inflammation. Blood lead level in hemodialysis patients might increase the intensity or have an additive role of pruritus caused by other more common risk factors. This study aims to further verify or deny the relation between blood lead level and uremic pruritus. Design, setting, participants, &amp; measurements The present study is a cross sectional study that investigates the relation between blood lead levels and pruritus in patients with end stage renal disease receiving hemodialysis. 50 patients were enrolled in this study, all were on regular hemodialysis 3 times a week, patients with primary skin diseases (psoriasis, erythroderma, etc), HCV positive patients, patients with chronic liver disease and patients with malignancies were excluded. Patients with PTH levels over 300 pg/dl And those with corrected calcium and phosphorus levels over 10.2 and 5.5 mg/dl Were excluded from the study. We divided the patients into 2 groups, group 1 (n = 10) with no pruritus and group 2 (n = 40) with varying degrees of pruritus. Results There was a significant difference in serum lead levels and ferritin levels between group 1 and 2. Group 2 was further divided according to intensity of Pruritus by VAS score into mild (n = 10), moderate (n = 20) and severe pruritus (n = 10) There was also a statistically significant difference in serum lead levels in different groups of intensity of pruritus, having higher serum lead levels in patients who exhibited severe pruritus. And there was a significant correlation between blood lead and duration of dialysis Conclusion Uremic pruritus is a multi-factorial phenomenon, our study showed that Blood lead level in HD patients might increase the intensity and have an additive role in the pathogenesis of pruritus in dialysis patients hence Blood lead level is positively correlated with Uremic Pruritus. We were able to demonstrate that both blood lead and duration of dialysis together are the most sensitive predictors for pruritus, the best cut off value for blood lead is 6 together with duration above 10 with high sensitivity, specificity and efficacy.

To investigate the risk of lead poisoning among household members exposed to 'backyard' battery repair shops (BBRS) in Kingston, Jamaica, environmental and blood lead (PbB) were measured at 24 households (112 individuals) with a BBRS worker or located at a BBRS premises and at 18 neighbourhood control households (74 individuals). Elevated PbB (greater than or equal to 25 micrograms per decilitre [micrograms/dl]) was common among subjects of all ages living at BBRS premises, especially among children less than age 12, 43% of whom had PbB greater than 70 micrograms/dl. Potentially hazardous soil and house dust lead levels were also common at BBRS premises, where 84% of yards had soil lead levels above 500 parts per million (geometric mean 3388 parts per million [ppm] at BBRS premises households with a BBRS worker). Geometric mean blood and environmental lead levels were significantly lower at control households, where less than 10% of subjects in all age groups had elevated PbB (maximum 33 micrograms/dl). Sharing a premises with a BBRS was a stronger determinant of household blood lead and environmental contamination than was the presence of a BBRS worker in a household. Blood lead levels were associated with soil and house dust lead levels in all age groups. We conclude that small battery repair shops, which have also been described in other developing countries, create a high lead poisoning risk for nearby residents.

Little is known about childhood lead absorption in South Africa. In this study a cross-sectional analytic survey was carried out to determine the blood lead levels and associated risk factors for inner-city, first-grade schoolchildren. Blood lead analyses, hematological and anthropometric measurements were conducted, and a pretested questionnaire was administered to parents to identify risk factors for lead exposure. In a detailed environmental study, daily air and dust samples were collected over a period of 1 year from several sites in the study area, contemporaneously with the blood and questionnaire surveys. Spatial and temporal variations in atmospheric lead were determined. It was found that 13% of mixed race children, but no white children, had blood lead levels greater than or equal to 25 micrograms/dL, the U.S. action level. Air lead levels averaged around 1 microgram/m3, and dust lead levels ranged from 410 to 3620 ppm. Environmental lead levels were significantly elevated near heavy traffic, where Environmental Protection Agency standards were exceeded mainly during winter months. Baseline exposure was of significance in influencing blood lead levels of children attending schools in direct proximity to heavy traffic, where blood lead levels were elevated irrespective of other influencing factors. Primary and secondary preventive measures are urgently needed in South Africa to reduce environmental lead exposure. At the time of the study, South Africa had one of the highest levels of lead in gasoline in the Western World, namely, 0.836 g/L. Although levels have subsequently been reduced, this is typical of the situation in many African countries today.