Occupational lead toxicity in battery workers

Assessment of heavy metals among auto workers in metropolitan city: a case study

In recent decades, heavy metals (HMs) have emerged as a global health concern. Unfortunately, in Pakistan, there is a general lack of awareness regarding the potential health risks associated with HMs pollution among automobile workers. Herein, we investigated the concentration of heavy metals such as lead (Pb), cadmium (Cd), and chromium (Cr) among automobile workers who were occupationally exposed in Mingora City, Khyber Pakhtunkhwa, Pakistan. Three different automobile groups, i.e., battery recyclers, spray painters, and mechanics were studied in detail. A total of 40 blood samples were collected from automobile workers groups while 10 blood samples were collected as control individuals from different locations in the study area. We investigated heavy metals concentration with a standard method using an atomic absorption spectrometer AAS (PerkinElmer Analyst 700, United States). Based on our findings, the battery recycling group displayed the most elevated Pb levels (5.45 ± 2.11 μg/dL), exceeding those of both the spray painters' group (5.12 ± 1.98 μg/dL) and the mechanics' group (3.79 ± 2.21 μg/dL). This can be attributed to their higher exposure to Pb pollution resulting from the deterioration, dismantling, grinding, or crushing of old batteries. In the context of chromium (Cr) exposure, a similar trend was observed among the battery recycling group, as well as the spray painters and mechanics groups. However, in the case of cadmium (Cd), the mechanics' group exhibited the highest level of exposure (4.45 ± 0.65 μg/dL), surpassing the battery recycling group (1.17 ± 0.45 μg/dL) and the spray painters' group (1.35 ± 0.69 μg/dL), which was attributed to their greater exposure to welding fumes and other activities in their workplace. We believe that our findings will encourage regulatory measures to improve the health of automobile workers. However, further work is needed to determine various health-related issues associated with heavy metal exposure among automobile workers.

[Lead Exposure as Cause of a Clinical Scenario of Cardiac Arrhythmias]

The recycling of used batteries has raised public health concerns as this activity is associated with occupational and environmental exposure to lead. We describe the case of a 26-year-old woman who experienced palpitations associated with headaches, fatigue and insomnia. Blood tests showed anemia (Hb 11.9 g/dL) and a lead concentration of 59 μg/dL. This was reported about four months after starting work in a battery recycling company. She left the company and, reported a gradual decrease in symptoms about one month later. The analytical study revealed a normalization of hemoglobin levels (12.2 g/dL) and a decrease in blood lead levels to 23.4 μg/dL. The health effects of lead exposure are nonspecific, and its diagnosis requires a high degree of suspicion. In this context, the collaboration between the Attending Physician and the Health and Safety Departments of companies is important.

"Blood lead level among battery factory workers in low and middle-income countries: Systematic review and meta-analysis"

Introduction

Lead is one of the most health-hazardous causes of acute and chronic poisoning at workplaces. A limited study was conducted on the blood lead concentration among battery factory workers in low and middle-income countries. Therefore, this study will improve workplace health and safety conditions of workers in this sector and serve as baseline data for further studies in this segment of the working setup.

Objective

This review aims to identify the pooled mean blood lead level among battery factory workers in low and middle-income countries.

Methods

The search methods considered the following electronic bibliographic databases: google scholar, PubMed, and other gray literature. A funnel plot and Begg test were used to see the publication bias. The heterogeneity of studies was checked using I-square statistics with a cut of point 75% and the Joanna Briggs Institute (JBI) quality assessment tool was applied to ensure the quality of the included articles. A random-effect model was applied to pool the blood lead level intoxication. The sub-group analysis and Meta-regression analysis were conducted by country and year of publication to control heterogeneity and to show variation. We included the articles published from 2000 to 2021 year in the English language.

Results

Through the search strategies, 135 articles were identified and 43 full-text articles were selected for evaluation, and finally, eighteen (18) articles fit the inclusion criteria. From the 18 studies included in the meta-analysis, the mean pooled blood lead level of workers was 37.996 μg/dl (95% CI: 30.680-45.312) which is higher than the threshold limit value set by American conference of governmental industrial hygienists (20 μg/dl). In subgroup analysis by year in the random effect model, the pooled mean of blood lead level from 2006 to 2011= 43.20 μg/dL (35.91-50.50), 2012-2015 = 37.78 μg/dl (25.23-50.29), and 2016-2020 = 36.53 μg/dl (19.44-53.62).

Conclusions

This review showed that the pooled mean blood lead level of workers exposed to lead battery factories was (37.996 μg/dl) which is above the threshold limit value (20 μg/dl). Therefore, attention should be given by employers, government, and researchers to improve the health of working populations exposed to lead exposure in low and middle-income countries through the provision of occupational health and safety services like periodical medical checkups, treatments, and provision of training and adequate and appropriate personal protective equipment.Systematic review registration: Identifier: CRD42022322827.

Structure-guided development of Pb2+-binding DNA aptamers

Owing to its great threat to human health and environment, Pb²⁺ pollution has been recognized as a major public problem by the World Health Organization (WHO). Many DNA aptamers have been utilized in the development of Pb²⁺-detection sensors, but the underlying mechanisms remain elusive. Here, we report three Pb²⁺-complexed structures of the thrombin binding aptamer (TBA). These high-resolution crystal structures showed that TBA forms intramolecular G-quadruplex and Pb²⁺ is bound by the two G-tetrads in the center. Compared to K⁺-stabilized G-quadruplexes, the coordinating distance between Pb²⁺ and the G-tetrads are much shorter. The T3T4 and T12T13 linkers play important roles in dimerization and crystallization of TBA, but they are changeable for Pb²⁺-binding. In combination with mutagenesis and CD spectra, the G8C mutant structure unraveled that the T7G8T9 linker of TBA is also variable. In addition to expansion of the Pb²⁺-binding aptamer sequences, our study also set up one great example for quick and rational development of other aptamers with similar or optimized binding activity.

Evaluation of DNA Damage and Expressions of DNA Repair Gene in Occupationally Lead Exposed Workers (Jodhpur, India)

Occupational exposure to lead (Pb) remains a significant concern for worker's health working in different factories. There are many discrepancies among the results regarding the studies of genotoxicity of Pb. The present study aimed to evaluate DNA damage and expressions of DNA repair genes (OGG1, XRCC1, and XPD) in occupationally Pb-exposed workers of Jodhpur, India. The study consisted of 100 occupationally Pb-exposed workers and 100 controls (non-exposed) with no history of occupational exposure. Pb levels were determined by atomic absorption spectrophotometry, serum 8-hydroxy-2-deoxyguanosine (8-OHdG) concentrations were measured by ELISA, and expressions of DNA repair genes (OGG1, XRCC1, and XPD) were estimated by RT-PCR. The results indicated significantly higher levels of Pb in the exposed group as compared with the non-exposed group (p < 0.0001). Serum 8-OHdG concentrations were significantly higher (p < 0.0083), and all three DNA repair genes were significantly downregulated (fold change: OGG1, 0.188; XRCC1, 0.125; XPD, 0.133) in the Pb-exposed group as compared with the non-exposed. In conclusion, the study findings suggest that Pb exposure is associated with increased DNA damage and reduced DNA repair capacity, which may lead to serious health issues in occupationally Pb-exposed workers.

Assessement of Blood Lead and Cadmium Levels in Occupationally Exposed Workers of Jodhpur, Rajasthan

In spite of the established knowledge regarding their toxicities, occupational exposure to heavy metals like lead and cadmium still continues because of their wide distribution in environment. Due to lack of awareness, most of the workers usually eat, smoke, drink at their workplace which may aggravate the metal exposure. The present study was planned to assess the blood levels of lead and cadmium in occupationally exposed workers of Jodhpur (India). A total of 110 individuals working in different industrial set ups (furniture, metal handicraft, welders) of Jodhpur district (exposed group), aged between 20 and 60 years and 97 apparently healthy people (controls) with no history of occupational heavy metal exposure aged between 25 and 60 were recruited. Details of personal habits and demographics were recorded by means of self-developed questionnaire. 5 ml of whole blood was drawn from every individual. Metal levels were measured by graphite furnace atomic absorption spectrophotometer. Statistical analysis was done using GraphPad Prism Software. Results showed that Blood Lead Level and Blood Cadmium Level (CdB) were significantly higher in the exposed group as compared to the non-exposed group. Significant age and gender-based differences were found in terms of blood cadmium levels but no such difference was observed in case of blood lead. The study also revealed that higher blood levels of these metals in workers are influenced by their occupational practices, lack of protection against workplace environment pollutants, thus increasing their susceptibility to metal toxicity.

Lead poisoning; a neglected potential diagnosis in abdominal pain

Background

Abdominal pain may be a presenting symptom of lead poisoning and is often difficult to diagnose. This study aimed to determine the prevalence of abdominal pain in patients seen in the Laghman Hakim Hospital ED and GI clinic who were lead-intoxicated, with or without opiate use disorder.

Methods

Between July 2017 and January 2018, patients seen in the ED and GI clinic of Loghman Hakim Hospital with unexplained abdominal pain or abdominal pain resistant to treatment were enrolled. Informed consent was obtained from potential enrollees. For standardization, a pre-designed data collection tool was developed for uniform data acquisition. Opiate use was determined historically. For this study, lead poisoning was defined as a blood lead level (BLL) greater than or equal to 30 μg/dL (1.45 μmol/L) with concomitant GI symptoms.

Results

Of 125 patients admitted, 28 (22.4%) had BLLs higher than 30 μg/dL. None of the patients had signs and symptoms of opioid withdrawal syndrome during evaluation. Elevated BLLs were significantly correlated with oral opium use/abuse, history of addiction for over the preceding 12 years. The daily opium use was more than 2.75 g. There was a statistical correlation between lead toxicity and abdominal pain consistency and intensity, constipation, and paresthesias. Anemia, leukocytosis, and abnormal liver enzyme tests were laboratory findings associated with lead toxicity. Four patients died, one of whom was diagnosed with lead toxicity.

Conclusion

Lead toxicity should be considered in the potential differential diagnosis of severe and resistant abdominal pain in patients referring to general EDs or GI clinics if a positive history of opium abuse exists.

Blood lead levels among the occupationally exposed workers and its effect on calcium and vitamin D metabolism: A case-control study

INTRODUCTION

Lead (Pb) is one of the major occupational pollutants present in the developed and developing countries including India. In humans, Pb can cause a wide range of biological effects depending upon the level and duration of exposure. The goal of this study was to evaluate the blood lead levels (BLLs) and its associated effects on vitamin D and calcium metabolism, among the workers occupationally exposed to Pb.

MATERIALS AND METHODS

This cross-sectional, case-control study was conducted for a period of 18 months (January 2017 to July 2018). A total of 160 subjects were included in the study (80 in each, Pb-exposed group and control group). The blood Pb levels were quantified by using an inductively coupled plasma mass spectrometry with triple quadrupole technology (iCAP™ TQ ICP-MS). Other biochemical parameters were estimated using fully automatic analyzer by RANDOX, RX-imola, Crumlin, UK and Johnson and Johnson, VITROS® ECiQ, Immunodiagnostic system, Ortho Clinical Diagnostics, New Jersey, USA.

RESULTS

Upon analysis it was observed that serum calcium, phosphorous, and vitamin D levels were significantly decreased (8.35 ± 0.42 mg/dl, 3.07 ± 0.34 mg/dl, and 28.82 ± 10.81 ng/ml respectively; P < 0.001), whereas the BLL and serum iPTH levels were significantly increased (38.02 ± 19.92 μg/dl and 116.78 ± 19.93 pg/ml respectively; P < 0.001) in Pb exposed subjects as compared to control subjects.

CONCLUSION

Our study results demonstrated that high BLL significantly alter vitamin D and calcium metabolism. The data extrapolated from our study emphasizes the necessity of surveillance in exposed workers. As the associated deleterious effects of Pb-exposure can be serious, we propose that a routine-periodical screening of the workers exposed to lead should be conducted.

Lead and zinc exposure in the blood of workers in municipal waste management

Improper treating, sorting, storing, transporting, or disposing of wastes poses a potential risk to the health of humans and the environment. The workers of waste management plants are at risk of exposure to heavy metals and their toxic and hazardous effects through respiratory or cutaneous routes. Accordingly, concentrations of two heavy metals in the biological samples of workers of a municipal waste management (MSW) plant in Iraqi Kurdistan were measured in 139 persons who worked for at least 6 months. Blood and plasma samples were collected to measure lead and zinc concentrations, respectively. Their working units, occupational history, smoking habits, and the distance living from the landfill site were recorded in a predesigned questionnaire. A blood lead level (BLL) of less than 40 μg/dL was considered a safe cutoff. The lower limit of normal fasting plasma zinc was set at 70-120 μg/dL. The study showed that the mean age of the workers was 33.43, ranging from 16 to 67 years old, and they worked for the last 4.93 years. Further, 22.3% of the staff had previous experience in a job with suspected exposure to heavy metals. The mean BLL concentrations and the plasma zinc level were 31 μg/dl and 5.77 μg/dl, respectively. The study did not find a substantial difference in lead and zinc among workers with different characteristics. We did not find any predictor for lead and zinc concentrations in our sample. The study showed that the mean levels of lead and zinc were lower than the permitted ranges.

Blood Lead Levels in Occupationally Exposed Workers Involved in Battery Factories of Delhi-NCR Region: Effect on Vitamin D and Calcium Metabolism

Workers involved in battery manufacturing or recycling factories are occupationally exposed to high concentrations of lead. In humans, lead can cause a wide range of biological effects depending upon the level and duration of exposure. The purpose of this study was to find out the blood lead levels (BLL) in occupationally exposed workers involved in battery industry in Delhi NCR region and to study whether lead affected the vitamin D (vit D) and calcium metabolism. For this study 100 occupationally lead-exposed battery workers (LEBW) and 100 non-lead exposed controls (NLEC) were recruited. BLL were measured using inductively coupled plasma optical emission spectrometer (ICP-OES) technique while ELISA was performed to quantify the serum vit D levels in the study subjects. Routine biochemical parameters were measured by chemistry autoanalyzers. Statistical analysis was done using appropriate statistical tools. Results showed that BLL were significantly higher in LEBW as compared to NLEC (p < 0.0001). Serum vitamin D, calcium and phosphorus levels were significantly decreased in battery workers as compared to controls (p < 0.005). Spearman's rank correlation analysis showed significant negative correlation of BLL with serum Vitamin D and calcium levels. Significant positive correlation was observed between BLL and duration of lead exposure. Weak negative correlation was also observed between BLL and vit D even after adjusting for smoking status. In conclusion, this study demonstrated that higher BLL significantly alters the vit D and calcium metabolism.

Oxidative Stress Indices as Markers of Lead and Cadmium Exposure Toxicity in Auto Technicians in Ibadan, Nigeria

Auto technicians (auto mechanics, panel beaters, battery chargers, and auto painters) are among the most valuable work force in the society. Reports on oxidative stress in persons occupationally exposed to mixed chemicals abound; however, few have narrowed down specifically on auto technicians, while even fewer have stratified the exposure in the different subgroups of auto technicians. This study evaluated the antioxidant status in auto technicians routinely exposed to lead and cadmium and stratified the results of exposure by different subgroups of auto technicians in Ibadan, Nigeria. Sixty-five apparently healthy males (aged 18 to 65years) were selected based on specific inclusion criteria using a structured questionnaire. Thirty-four were cases consisting of participants routinely working as auto technicians or apprentices(≥2years) while controls were thirty-one nonoccupationally exposed male members of staff/students of the University College Hospital, Ibadan, Nigeria. Blood was collected from all participants and analyzed for the presence of lead, total antioxidant capacity (TAC), and total plasma peroxides (TPP); oxidative stress index (OSI) was calculated. Urine samples collected from all participants were analyzed for the presence of urinary lead and cadmium using standard laboratory methods. Although values of TAC in cases (22538 ± 8726.54) were not statistically different from what was obtained in controls (26741.87 ± 8696.68), TPP and OSI were statistically higher in cases than in controls (183.88 ± 53.39 and 120.16 ± 70.54, respectively, and 0.93 ± 0.45 and 0.49 ± 0.33, respectively). The blood lead level in cases (10.11 ± 4.47) was significantly higher than in controls (7.72 ± 1.22) while elevated urinary lead and cadmium levels were observed in cases (0.65 ± 0.21 and 0.34 ± 0.11, respectively) compared to controls (0.52 ± 0.19 and 0.27 ± 0.10, respectively). Raised TPP and OSI levels-hallmark of active lipid peroxidation-found to be highest among panel beaters compared to others may be prognostic of membrane-damaging diseases in this subgroup of auto technicians.

Assessment of lead exposure among automobile technicians in Khyber Pakhtunkhwa, Pakistan

Exposure to Pb among automobile technicians in selected towns of Khyber Pakhtunkhwa Province, Pakistan, was studied using a questionnaire, biological sampling (blood, hair, nails), and analysis of Pb biomonitoring data across various subgroups of occupation, age, and years of exposure. The study population included exposed automobile technicians (n=50) and a control group (n=50). The automobile technicians were further stratified into 4 groups: mechanics, auto-body technicians, electricians, and painters. Mean Pb levels in biological samples of the automobile technicians were significantly higher than in the control group (P<0.01). The Pb concentrations (mean±standard deviation) in whole blood, hair, and nails of automobile technicians were 65.3±41.9μgdL^-1, 23.6±11.2mgkg^-1 and 29.7±14.5mgkg^-1, respectively, whereas concentrations in the control group were 21.7±17.6μgdL^-1, 4.8±3.4mgkg^-1 and 7.2±3.9mgkg^-1. Fifty two percent of the automobile technicians had blood levels >50μgdL^-1, but only 14% of the control group exceeded this level. Considering that Pb blood levels of 50μgdL^-1 exceed maximum concentrations recommended by leading public health organizations, appropriate measures should be taken to protect the welfare of the exposed automobile technicians and their families.

Assessment of Lead Exposure and Urinary-δ-aminolevulinic Acid Levels in Male Lead Acid Battery Workers in Tamil Nadu, India

BACKGROUND

Exposure to lead (Pb) affects multiple health outcomes and physiological systems. In adults, even small increases in blood Pb levels have been associated with decreased glomerular filtration rate, increased risk of hypertension and increased incidence of essential tremor. To date, there have been few Pb-exposure assessments using the United States Occupational Health and Safety Administration (OSHA) regulations.

OBJECTIVE

The aim of the present study was to assess Pb-exposure in terms of elevated blood lead levels (BLL) and urinary-δ-aminolevulinic acid (U-δ-ALA) levels of workers exposed to Pb in the lead acid battery industry in Tamil Nadu, India based on Pb exposure regulations set by the American Conference of Governmental Industrial Hygienists (ACGIH) and OSHA.

MATERIALS AND METHODS

BLLs and U-δ-ALA were estimated in 449 male workers exposed to Pb across ten different job categories in a lead acid battery factory. Worker BLLs were estimated using atomic absorption spectrophotometry and U-δ-ALA was estimated using spectrophotometry.

RESULTS

The Biological Exposure Index of the American Conference of Governmental Industrial Hygienists (BEI-ACGIH) were used to assess Pb exposure. BLLs <30 μg/dL were found in 63.5% of workers, and 36.5% of workers had BLLs>30 μg/dL. The present study also assessed Pb exposure using OSHA regulations and found that 83.3% of workers had BLLs <40 μg/dL and 16.7% of workers had BLLs>40 μg/dL. Among these workers, 0.7% of workers had BLLs >60 μg/dL. An excessive excretion of U-δ-ALA (20-40 mg/L) was noted in pasting area workers (2.6%) followed by executives (2.2%) and assembly workers (0.9%).

CONCLUSIONS

Workers in the job categories of pasting and assembly, as well as executives, are at high risk of Pb exposure compared to other job categories. We recommend placing humidifiers on the roof and keeping a water bath closer the to plate cutting area to reduce fugitive Pb dust emissions. We recommended workers with BLLs >60 μg/dL be removed from jobs involving Pb exposure and return to work only when their BLLs are <40 μg/dL.

PARTICIPANT CONSENT

Obtained.

ETHICS APPROVAL

The study was approved by the ethics committee of the Regional Occupational Health Centre (Southern) Bengaluru, part of the National Institute of Occupational Health of India.

COMPETING INTERESTS

The authors declare no competing financial interests.

Environmental Exposures and Cardiovascular Disease: A Challenge for Health and Development in Low- and Middle-Income Countries

Environmental exposures in low- and middle-income countries lie at the intersection of increased economic development and the rising public health burden of cardiovascular disease. Increasing evidence suggests an association of exposure to ambient air pollution, household air pollution from biomass fuel, lead, arsenic, and cadmium with multiple cardiovascular disease outcomes, including hypertension, coronary heart disease, stroke, and cardiovascular mortality. Although populations in low- and middle-income countries are disproportionately exposed to environmental pollution, evidence linking these exposures to cardiovascular disease is derived from populations in high-income countries. More research is needed to further characterize the extent of environmental exposures.

Effect of Lead Exposure on the Status of Reticulocyte Count Indices among Workers from Lead Battery Manufacturing Plant

Earlier studies conducted on lead-exposed workers have determined the reticulocyte count (RC) (%), but the parameters of Absolute Reticulocyte Count (ARC), Reticulocyte Index (RI), and Reticulocyte Production Index (RPI) were not reported. This study assessed the effect of lead (Pb) exposure on the status of reticulocyte count indices in workers occupied in lead battery plants. The present cross-sectional study was carried out on 391 male lead battery workers. The blood lead levels (BLL) were determined by using an Atomic Absorption Spectrophotometer. The RC (%) was estimated by using the supravital staining method. The parameters, such as ARC, RI, and RPI, were calculated by using the RC (%) with the red cell indices (RBC count and hematocrit). The levels of RBC count and hematocrit were determined by using an ABX Micros ES-60 hematology analyzer. The levels of reticulocyte count indices - RC (%), ARC, RI, and RPI significantly increased with elevated BLL. The association between BLL and reticulocyte count indices was positive and significant. The results of linear multiple regression analysis showed that the reticulocyte count (β = 0.212, P < 0.001), ARC (β = 0.217, P < 0.001), RI (β = 0.194, P < 0.001), and RPI (β = 0.208, P < 0.001) were positively associated with BLL. The variable, smoking habits, showed a significant positive association with reticulocyte count indices: RC (%) (β = 0.188, P < 0.001), ARC (β = 0.174, P < 0.001), RI (β = 0.200, P < 0.001), and RPI (β = 0.151, P < 0.005). The study results revealed that lead exposure may cause reticulocytosis with an increase of reticulocyte count indices.