Systematic Review and Meta-Analysis of Mercury Exposure among Populations and Environments in Contact with Electronic Waste

Abstract

Electronic waste (e-waste) recycling releases mercury (Hg) into the environment, though to our knowledge Hg levels at such sites have yet to be examined on a worldwide basis. A systematic review of scientific studies was conducted to extract, analyze, and synthesize data on Hg levels in e-waste products, environments near recycling sites, and in people. Data were extracted from 78 studies from 20 countries, and these included Hg levels in 1103 electrical and electronic products, 2072 environmental samples (soil, air, plant, food, water, dust), and 2330 human biomarkers (blood, hair, urine). The average Hg level in products was 0.65 μg/g, with the highest levels found in lamps (578 μg/g). Average soil and sediment Hg levels (1.86 μg/g) at e-waste sites were at least eight times higher than at control sites. Average urinary Hg levels (0.93 μg/g creatinine) were approximately two-fold higher among e-waste workers versus control groups. Collectively, these findings demonstrate that e-waste recycling may lead to Hg contamination in environments and human populations in close proximity to processing sites. These findings contribute to a growing knowledge base of mercury exposure through diverse source–exposure pathways, and the work has potential policy implications in the context of the Minamata Convention.

Mercury as a Pollutant: Sources, Routes of Exposure, and Health Effects

“…Los trabajadores de vertederos municipales con presencia de desechos electrónicos presentan niveles de Hg en orina extremadamente altos, por su exposición a niveles de Hg que pueden superar los 29,000 ng/m 3 [14]. Se estima que las emisiones de Hg provenientes de los vertederos de electrónicos irán aumentando a lo largo de los años, debido a la creciente demanda de componentes electrónicos a nivel mundial.…”

Our evolved understanding of the human health risks of mercury

“…Several EEE products contain mercury (e.g., fluorescent lights, switches, batteries, phones, and computers) and after these products are burned and broken down for recycling, mercury may be released into the surrounding environment (Kyere et al 2017 ; Forti et al 2020 ). Through a systematic review of the scientific literature, the average mercury concentration in 1,103 e-waste products was 0.65 μg/g, with the highest values found in fluorescent lights, batteries, and LCD backlights (Aubrac et al 2022 ). In this same study, which examined 78 papers published between 2005 and 2022, mercury concentrations were reported from diverse media including water, dust, food, air, and plants.…”