October 15, 2020

Proposed NIOSH Study Would Examine Respiratory Morbidity in Styrene-Exposed Workers

A new study proposed by NIOSH would examine the prevalence of long-term respiratory morbidity in workers exposed to styrene. According to the agency, approximately 90,000 manufacturing workers are potentially exposed to the chemical in the United States. Styrene is primarily a synthetic chemical that is used in the production of automobile parts, boats, computer housings, food containers, and wind energy components. NIOSH states that workplace exposure to styrene has been associated with adverse health effects such as changes in color vision, mucous membrane irritation, hearing loss, neurocognitive impairment, and cases of non-malignant respiratory disease, including chronic obstructive pulmonary disease and obliterative bronchiolitis, a severe, irreversible lung disease. The agency hypothesizes that workers previously exposed to high concentrations of styrene—even those who spent less than one year on the job—will have a higher prevalence of respiratory symptoms and lung function abnormalities than workers exposed to concentrations of styrene lower than 5 parts per million.

NIOSH’s project would involve interviews and lung function testing of workers from two reinforced plastic boatbuilding plants that closed in 1989 and 1993. The agency intends to characterize work exposures by collecting detailed job histories and comparing them with historical exposure levels obtained from a past industrial hygiene survey. The NIOSH study would also examine the prevalence of respiratory morbidity by duration and level of styrene exposure, and seek to describe the prevalence of color vision impairment with the presence of respiratory morbidity.

Further details about NIOSH’s proposal are described in the Federal Register. Comments about the proposed study may be submitted online via Reginfo.gov until Oct. 30, 2020.