SEGH Articles

A human health risk assessment framework to improve the management of potentially toxic elements in informally recycled waste electronic and electrical equipment (WEEE)

04 February 2019
Dr Alessandra Cesaro, University of Salerno and Professor Andrew Hursthouse, University of the West of Scotland assess the human health risk of potentially toxic elements in informally recycled waste electronic and electrical equipment (WEEE)

Members of the EU COST Action ES140 ReCreew (http://www.recreew.eu/) have recently completed review studies which provide an assessment of the potential hazard from the informal recycling of WEEE. These activities include manual handling, sorting, component removal, crushing and grinding as well as burning and acid leaching, generate situations around the world where both operators and the wider community are exposed to emissions and residues from these activities. Substances released include a wider range of metallic elements and organic compounds form the component plastics and as a result of heating (burning or melting). Much of the WEEE collected in Europe is destined for third countries and these markets show quite dynamic changes, particularly with recent restrictions on waste import to China. 

The variability of physical and compositional characteristics and rapid growth in WEEE production creates an enormous challenge to establish appropriate methods of handling materials – particularly in the informal sector. ReCreew was concerned that the diverse methods of handling were difficult to assess systematically from a human health risk. Consequently, they embarked on a systematic study of the compositional variation and model processes to see whether there was an opportunity to provide some basis for assessment.

By using knowledge of the compositional features of individual printed circuit boards in WEEE components, an assessment based on theoretical inhalation route, ranked components on their basis of potential harm form a substance weighted perspective. This identified individual groups of components – with the top PCB (printer) nearly 4 times more hazardous than the second place (mobile phone) (Cesaro et al, 2018). Establishing the basis for prioritisation in health protection. Subsequently, a “Shrinking-Core” combustion model was used to look at emissions of metals and organic compounds (dioxins/furans) during open burning practice.  Based on mass weighted toxicity assessment, this clearly identified open burning of cables above computer and mobile phone PCBs (Cesaro et al, 2019).

These early assessments direct research to further develop realistic datasets for compositional variation of WEEE and in producing pragmatic guidance to engage with informal recycling communities and we hope to open the wider debate on resource recovery in the informal sector.


 

Cesaro, A, Belgiorno, V, Vaccari, M, Jandric, A, Chung, TD, Dias, MI, Hursthouse, A & Salhofer, S 2018, 'A device-specific prioritization strategy based on the potential for harm to human health in informal WEEE recycling' Environmental Science and Pollution Research, vol 25, no. 1, pp. 683–692. DOI: 10.1007/s11356-017-0390-7

Cesaro, A, Belgiorno, V, Gorrasi, G, Viscusi, G, Vaccari, M, Vinti, G, Jandric, A, Dias, MI, Hursthouse, A & Salhofer, S 2019, 'A relative risk assessment of the open burning of WEEE' Environmental Science and Pollution Research (accepted, in press).

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