Occupational toxic inhalation injury to cleaning chemicals during the COVID-19 pandemic, including a case series for disinfectants aerosolized through spray and fog application

The occupational burden of injury caused by exposure to cleaning chemicals during the pandemic is not well described. The objective of this study was to determine whether the COVID-19 pandemic was associated with a change in the rate of toxic inhalation (TI) injuries following occupational exposure to cleaning chemicals. This retrospective study spanned from July 1, 2017, to June 30, 2022, with January 1, 2020, designated as the pandemic start. TI cases were identified among workers’ compensation claims filed in Washington State, USA using keyword text search and diagnostic and insurance codes. Qualitative claim data were reviewed to determine the frequency of cases with exposure to aerosolized disinfectants following spray or fog application. Rates of TI claims per full-time equivalent (FTE) workers were compared in the pre- and pandemic periods. Out of the 440 TI claims identified, 30% involved exposure to disinfectants and 13% had a diagnosis of work-related asthma. There was a decline in the overall rate of TI claims in the pre- vs. pandemic period (8.9/100,000 FTE vs. 7.4/100,000 FTE, respectively). However, the proportion of exposures to disinfectants increased during the pandemic period. Four industries, particularly “Transportation and Warehousing,” experienced an increase in TI injury rate. Fog or spray application of disinfectants was involved in 20 cases (including 14 in bus transportation) during the pandemic, compared to zero cases in the pre-pandemic period. In Washington State, the COVID-19 pandemic was associated with industry-specific increased TI injury rates due to cleaning chemicals, but not an overall increased rate. A case series emphasizes that aerosolized disinfectants are a toxic inhalation risk for workers. Studies to further characterize this practice and these injuries are warranted. Prevention efforts should utilize the hierarchy of controls as well as address hazard awareness, product over-application, and the need to estimate and uphold a safe re-occupation time after fog or spray application of disinfectants.