Work Task Association with Lead Urine and Blood Concentrations in Informal Electronic Waste Recyclers in Thailand and Chile.

The informal recycling of electronic waste ("e-waste") is a lucrative business for workers in low- and middle-income countries across the globe. Workers dismantle e-waste to recover valuable materials that can be sold for income. However, workers expose themselves and the surrounding environment to hazardous agents during the process, including toxic metals like lead (Pb). To assess which tools, tasks, and job characteristics result in higher concentrations of urine and blood lead levels among workers, ten random samples of 2 min video clips were analyzed per participant from video recordings of workers at e-waste recycling sites in Thailand and Chile to enumerate potential predictors of lead burden. Blood and urine samples were collected from participants to measure lead concentration. Boosted regression trees (BRTs) were run to determine the relative importance of video-derived work variables and demographics, and their relationship with the urine and blood concentrations. Of 45 variables considered, five job characteristics consisting of close-toed shoes (relative importance of 43.9%), the use of blunt striking instruments (14%), bending the back (5.7%), dismantling random parts (4.4%), and bending the neck (3.5%) were observed to be the most important predictors of urinary Pb levels. A further five job characteristics, including lifting objects <20 lbs. (6.2%), the use of screwdrivers (4.2%), the use of pliers/scissors (4.2%), repetitive arm motion (3.3%), and lifting objects >20 pounds (3.2%) were observed to be among the most important factors of blood Pb levels. Overall, our findings indicate ten job characteristics that may strongly influence Pb levels in e-waste recycling workers' urine and blood.

Metal Levels, Genetic Instability, and Renal Markers in Electronic Waste Workers in Thailand.

BACKGROUND: Informal electronic waste (e-waste) recycling is an increasingly important industry worldwide. However, few studies have studied the health risks in this group of workers. OBJECTIVE: To assess the associations between occupational exposures to metals and genetic instability and renal markers among e-waste recycling workers. METHODS: We recruited informal e-waste recycling workers from a community in northeastern Thailand. Participants completed a questionnaire, several health measurements, and provided urine and blood samples, which we then analyzed for a number of metals including lead (Pb), cadmium (Cd), and manganese (Mn). Samples were analyzed for a marker of RNA and DNA damage (ie, oxidative stress), 8-hydroxy-2'-deoxyguanosine (8-OHdG). Glomerular filtration rate (GFR) and fractional excretion of calcium (FECa%) were measured as markers of renal function. Correlations and regression models were used to assess associations between these various factors. RESULTS: We found significantly higher levels of Cd and Pb in blood of men compared with those in women. Men who worked >48 hours/week had significantly higher levels of 8-OHdG compared with men who worked ≤48 hours/week. Smoking was significantly associated with higher blood Pb and Cd concentrations among men. CONCLUSION: Our results suggest gender differences in both blood concentrations of metals associated with e-waste recycling and smoking and highlight potentially elevated oxidative stress associated with longer work hours. Health promotion efforts are needed among informal e-waste recyclers to reduce possible risks of renal damage and cancer.

Mercury exposure, risk factors, and perceptions among women of childbearing age in an artisanal gold mining region of the Peruvian Amazon.

Recent studies from the Madre de Dios region of Peru report elevated mercury exposure among the general population. Our objective was to assess mercury exposure, risk factors, risk perceptions, and knowledge among women of childbearing age, a population of concern due to risks to infant and fetal health. We collected hair samples and administered a survey among 200 women aged 18-49 years residing in Madre de Dios. Hair total mercury (THg) concentrations were analyzed in accordance with EPA Method 7473. Associations between exposures and potential risk factors were analyzed using generalized linear mixed models. Geometric mean hair THg concentration (±standard deviation) for all participants was 1.62 ±â€¯2.54 µg/g (range: 0.01-30.12 µg/g), and 67 participants (33.5%) had concentrations above the 2.2 µg/g reference dose established by the World Health Organization (WHO). Higher exposure was significantly associated with higher fish consumption (p = 0.03) and less mercury knowledge (p < 0.0001), but not with age or educational attainment. Most participants (86.2%) expressed concern about mercury contamination, but few (26.2%) had knowledge of the health risks associated with exposure. Many residents consumed fish species previously found to have low mercury concentrations, but more than 25% of participants reported consuming fish species with high mercury concentrations. We did not observe cross-sectional differences in fish intake among women who were pregnant or breastfeeding at the time of data collection.

Self-Reported Health and Metal Body Burden in an Electronic Waste Recycling Community in Northeastern Thailand.

OBJECTIVE: This study aims to summarize electronic waste (e-waste) worker health; examine associations between health and sociodemographic characteristics; and metal body burden. METHODS: In 2016, 131 e-waste recycling workers were enrolled in the study, completed a questionnaire, and gave blood and urine samples for heavy metal concentration assessment (lead, cadmium, copper, zinc, nickel). The relationship between symptoms, general health, and metals is assessed via generalized estimating equation models (adjusted for age, education, sex, and village). RESULTS: Cadmium in blood and copper in serum were most consistently associated with higher odds of poor health and prevalence of symptoms. We found inconsistent results between general health, symptom severity, and urinary nickel. Higher blood lead levels (BLL) were associated with fewer self-reported symptoms. CONCLUSIONS: Exposure to certain metals in e-waste recycling communities may adversely impact health status.

A Review of Biomarkers Used for Assessing Human Exposure to Metals from E-Waste.

Electronic waste recycling presents workers and communities with a potential for exposures to dangerous chemicals, including metals. This review examines studies that report on blood, hair, and urine biomarkers of communities and workers exposed to metals from e-waste. Our results from the evaluation of 19 publications found that there are consistently elevated levels of lead found in occupationally and non-occupationally exposed populations, in both the formal and the informal e-waste recycling sectors. Various other metals were found to be elevated in different exposure groups assessed using various types of biomarkers, but with less consistency than found in lead. Antimony and cadmium generally showed higher concentrations in exposed groups compared to reference group(s). Mercury and arsenic did not show a trend among exposure groups due to the dietary and environmental considerations. Observed variations in trends amongst exposure groups within studies using multiple biomarkers highlights the need to carefully select appropriate biomarkers. Our study concludes that there is a need for more rigorous research that moves past cross-sectional study designs, involves more thoughtful and methodical selection of biomarkers, and a systematic reporting standard for exposure studies to ensure that results can be compared across studies.

Health Assessment of Electronic Waste Workers in Chile: Participant Characterization.

Little research has been done to evaluate the occupational health of electronic waste (e-waste) recycling workers in Latin America. The objective of this study was to complete comprehensive health evaluations on e-waste recycling workers in Chile and to compare those that work in informal (i.e., independent) to those that work in formal (i.e., established company) settings. A cross-sectional study in the summer of 2017 recruited 78 informal recycling workers from two cities and 15 formal e-waste recycling workers from a single recycling facility to assess exposures and health outcomes. Participants completed a health questionnaire and underwent a full health assessment. Herein, only health questionnaire data are reported. Participants were primarily male, middle-aged, married with children, and had worked in e-waste recycling for an average of 12 years. Participants generally reported good health status, and their prevalence of chronic diseases was comparable to national rates. Workers frequently reported exposures to several occupational stressors, including noise and insufficient income, as well as other mental health stressors. Occupational injuries were commonly reported and use of safety equipment was low. Only a few significant differences, generally of a rather small magnitude, were found between informal and formal workers. In conclusion, from survey data, we did not identify major risks to health among e-waste workers, and only minor differences between workers in informal and formal settings.

Distribution and predictors of 20 toxic and essential metals in the umbilical cord blood of Chinese newborns.

Early-life exposure to heavy metals and/or trace metal imbalances can have negative developmental effects. Here we sought to characterize exposure profiles for 20 heavy metals and trace elements in umbilical cord blood plasma and identify demographic predictors of exposure. Twenty metals were measured in cord plasma from 357 Chinese infants using ICP-MS. Relationships between demographic variables and metals were analyzed using generalized linear models and logistic regression. Ten metals (antimony [Sb], cobalt [Co], cesium [Cs], copper [Cu], lead [Pb], molybdenum [Mo], rubidium [Rb], selenium [Se], strontium [Sr], titanium [Ti], zinc [Zn]) were detected in all samples. Season of birth was the strongest predictor of metals in cord blood across analyses. Infants born in the spring had 0.1-0.2 µg L-1 higher logAs and logCo in their cord blood (ß [95%CI] = 0.22 [0.01,0.42], p = 0.04; 0.11 [0.01,0.22], p = 0.04), while infants born in the summer had higher Sb, logB, logHg, and logZn (ß [95%CI] = 0.74 [0.24,1.24], p = 0.004; 0.11 [0.00,0.21], p = 0.04; 0.29 [0.08,0.49], p = 0.007; 0.18 [0.06,0.31], p = 0.005), compared to those born in fall/winter. Prenatal heavy metal exposure and/or trace metal deficiencies are global concerns because of increasing awareness of downstream developmental effects.