Physical processing, dismantling and hydrometallurgical treatment of e-waste: A systematic review of risks to occupational and public health

Abstract

Across the Global South, electrical and electronic waste (e-waste) is recovered using rudimentary and often dangerous methods in informal and unregulated facilities. Although these activities provide a valuable contribution to the global circular economy, their uncontrolled nature results in a risk of potentially hazardous substance emission into the environment from where they may pose considerable risk to both occupational and public health. Here, we focus a systematic PRISMA review on two distinct groups of activities undertaken in e-waste management in low- and middle-income countries (LIMICs): (i) Physical deconstruction and reclamation, involving dismantling assemblies of items and materials to recover value; and, (ii) hydrometallurgical treatment, involving the dissolution and suspension of precious metals using solvents (cyanide) and acids (aqua regia). For comparison purposes, we consolidate information on (i) and (ii) according to the types of substances evidenced; and identify, critically assess and rank most prevalent hazard-pathway-receptor (H-P-R) risk combinations experienced by people working across the Global South. Despite the proliferation of publications, evidence to assess risk is comparatively limited. Still, we are confident to highlight the extremely hazardous nature of work undertaken, often by children, handling highly hazardous substances without protective equipment to reclaim gold and other precious metals using hydrometallurgical processes. Emissions of hazardous substances, particularly potentially toxic elements (PTEs) from physical dismantling also represent a serious risk to health. Numerous sources speculatively link concentrations in the environment (a significant risk to children who have a tendency to eat soil) to e-waste dismantling processed. However, many of the sources that identify elevated substance concentrations in environmental media face difficulties in unambiguously and convincingly linking emissions from specific activities to the environmental concentrations, i.e. establishing causality. This key limitation presents us with a challenge for designing and implementing interventions to target, control and replace such highly risky resource recovery methods. Yet, such insufficient information cannot be used as an excuse for inaction, especially as our generalized H-P-R inferences here provide for sufficient interlinkages.

Public Awareness and Attitude on Municipal Solid Waste Management: A Case of University of Benin, Ugbowo Campus, Benin City

“…These substances may be inhaled, or distributed through the environment and subsequently ingested, up-taken by crops or absorbed through the skin. Several reports are recorded of evidence of emissions of substances from open burning that are classed as persistent organic pollutants (POPs), as well as those which are carcinogenic, mutagenic, cause immunological and developmental impairments, and may lead to reproductive abnormalities (Cook et al, 2020a, Velis andCook, 2020;Cook et al, 2020b, Cook et al, 2020c. In addition, burning organic waste produces chemicals such as dioxins and furans, which are suspected carcinogens that damage the nervous and immune systems and are harmful even in minuscule quantities (Down in the Dumps, The Economist., 2009).…”

A systematic review on sustainable E-waste management: challenges, circular economy practices, and a conceptual framework

“…When E-waste is burned, toxic fumes are emitted. These fumes can cause acute and chronic diseases, such as breathing diseases, skin cancer, allergies and even death (Awasthi et al, 2016a;Cook et al, 2020;Hicks et al, 2005). Inappropriate disposal of heavy elements such as lead and mercury in landfills can also lead MEQ 35,4 858 The current issue and full text archive of this journal is available on Emerald Insight at: https://www.emerald.com/insight/1477-7835.htm to the leakage of the groundwater (Pathak et al, 2017;Ueberschaar et al, 2017;Vural et al, 2021).…”