Occupational exposure to graphene: A pilot study combining workplace sampling with in vitro pulmonary toxicity assessment.

Graphene is increasingly produced and utilized in industrial applications, raising concerns regarding occupational exposure and associated health risks. While numerous toxicological studies have investigated the hazard potential of laboratory-produced graphene, relatively little is known about exposure to airborne graphene particles in actual workplace environments or the toxicity of samples collected in the workplace. In the present study, we combined occupational exposure assessment in a graphene production facility with in vitro toxicological evaluation of graphene samples produced by liquid-phase exfoliation of graphite versus particulate matter collected in the same production facility. Workplace air sampling was performed using stationary and personal samplers and particulate matter was collected for elemental carbon (EC) analysis, Raman microscopy-spectroscopy, and toxicological testing using human lung cell lines (A549 and BEAS-2B). Personal EC concentrations ranged from 3 to 484 μg/m3, with the highest exposure levels observed during graphite powder handling. Raman analysis confirmed the presence of graphene in the collected samples. Toxicological assessments showed that samples collected in the workplace did not elicit cytotoxic effects at the tested concentrations while dispersions of as-produced graphene evoked a dose-dependent loss of cell viability. Overall, this pilot study demonstrates the feasibility of combining occupational exposure measurements with toxicological testing of real-world samples and suggests that airborne materials collected during graphene production exhibit low hazard potential in human lung cells.