Occupational exposure to graphene-related materials: from workplace emissions to health risk assessment

Abstract

Graphene-related materials (GRMs) are among the most promising and versatile advanced materials, offering a wide range of applications. However, concerns regarding occupational exposure and associated safety challenges remain critical in their development and use. This study assessed exposures to GRMs, including graphene, graphene oxide (GO), reduced graphene oxide (rGO), and few-layer graphene (FLG), across seven real-world and three simulated exposure scenarios. Airborne GRM exposures in production, processing, and handling environments were measured and characterised using a standardised, tiered approach. Emissions were further evaluated through number-based dustiness testing of five GRMs (three rGOs, one GO, and one FLG), with the resulting dustiness data supporting exposure and lung deposition modelling. A health risk assessment was performed using both measured and modelled exposures. Workplace studies indicated low exposure during GRM production and related activities, primarily due to effective safety measures and practices. GRMs were typically processed in small quantities, in liquid form, or within closed systems, resulting in low exposure potential. Consequently, the risk to workers remained low, particularly with consistent use of personal protective equipment. However, handling GRMs as dry powders or in larger volumes may increase emissions, leading to higher exposures and potential health risks. Special attention is warranted during scale-up or process changes to prevent GRM emissions and exposures. Worker safety can be maintained by adapting traditional occupational hygiene practices to nanomaterial-specific considerations; nevertheless, a precautionary approach is recommended given prevailing uncertainties regarding long-term health effects.