Assessment of genotoxicity biomarkers in the scope of a human biomonitoring study in workers from E-waste management industries

Abstract

Electrical and electronic waste (e-waste) represents a pressing global challenge with its rapid growth and hazardous composition. This recycling sector often involves inadequate worker safety, exposing e-workers to harmful substances like heavy metals and flame retardants via several routes, causing significant short- and long-term health risks. Human Biomonitoring (HBM) is a useful tool in assessing exposure and associated health outcomes through biomarkers like micronucleus (MN) in blood or epithelial cells, enabling the identification of early biological changes and linking exposure to disease. This HBM study used two assays,- the Buccal Micronucleus Cytome (BMNCyt) assay and the Cytokinesis-Block Micronucleus Cytome (CBMNCyt) assay,- to assess potential genotoxic effects from occupational e-waste exposure. The BMNCyt assay, conducted under the HBM4EU initiative, targets buccal mucosa epithelial cells, a primary barrier against hazardous agents, thus assessing local genotoxic effects. The CBMNCyt assay in peripheral blood lymphocytes, conducted under the PARC Project, reliably measures structural and numerical chromosomal changes, reflecting a systemic effect. This research aimed to assess early biological effects from exposure to pollutants from e-waste in PBL and buccal epithelial cells of European e-waste workers, comparatively with control groups. The BMNCyt assay showed no significant differences in MN frequency between the exposed and control groups, while the CBMNCyt assay detected significantly increased frequencies of MN in the exposed compared with non-exposed groups. Factors like small sample sizes, interindividual differences, and the use of protective equipment might have influenced results. Demographic/lifestyle variables showed differing impacts on MN formation between assays, but also potential influence, thus the importance of their consideration. Concluding, expanding e-waste occupational health research to include more workers/activities within the waste management industry and broader biomonitoring efforts is paramount. Boosting the understanding of health risks associated with those activities will help developing protective measures and mitigation strategies to safeguard the exposed workers’ health.