8182269 A novel assessment of secondhand drug exposures on Pacific Northwest (USA) transit

<h3>Objective</h3> Transit operators have reported physical and mental health impacts related to drug use on transit. We sought to characterize air and surface concentrations of methamphetamine and fentanyl on transit in Washington and Oregon states to characterize transit operator exposure to these substances and help transit agencies prioritize interventions for operator well-being. <h3>Material and Methods</h3> We collected 78 total dust air samples (near the transit operator and elsewhere) and 102 surface samples via methanol-wetted swab from 11 buses and 19 trains. Background environmental samples were collected in nearby urban areas. Filters and swabs were analyzed for fentanyl and methamphetamine using LC/MS/MS. <h3>Results</h3> On transit samples, fentanyl was detected in 25% of air samples and 46% of surface samples; methamphetamine was detected in all air samples and 98% of surface samples. No fentanyl was found in environmental air or surface samples; methamphetamine was found in 3 (of 15) environmental air samples and 4 (of 14) environmental surface samples. The highest fentanyl air sample (0.14 µg/m3) was collected in the passenger area of a train, exceeding the ACGIH 8-hr TWA TLV of 0.1 µg/m3. No surface samples exceed the ACGIH fentanyl surface level TLV (10 ng/cm2). Other occupational standards or guidelines do not exist. <h3>Conclusions</h3> Fentanyl and methamphetamine were frequently found in the air and on surfaces of the vehicles in our study, at levels exceeding the environmental samples. Protecting transit operators from second-hand exposures, and from the stressors of witnessing and responding to smoking events, represents appropriate occupational health action consistent with the public health goal of smoke free workplaces. Where elimination is not possible, engineering and administrative controls (ventilation, cleaning) should be evaluated along with training and workplace supports for after operators observe or respond to drug events.