Project Overview: Cardno ChemRisk was retained by an adhesives manufacturer to assess the association between asthma and occupational exposure to methyl cyanoacrylate (MCA) and ethyl cyanoacrylate (ECA), components in superglue.  The manufacturer was responding to employee concerns regarding recent diagnoses of asthma.

Our Approach: Cardno ChemRisk scientists performed an epidemiological study, reviewing employee medical records and occupational histories covering a period of about 17 years for 450 employees at an adhesive production facility.  Additionally, we reviewed air sampling data to determine if potentially hazardous levels of MCA and ECA were present at the site.  Cardno ChemRisk conducted a cohort analysis using a Cox proportional hazards model and a case-control analysis that compared “suspected cases” of asthma to those whose pulmonary function tests (PFTs) remained within normal limits throughout their employment. Our analysis showed no evidence of an association between short-term or peak exposures to MCA or ECA and an increased risk of pulmonary obstruction.  However, results suggested that persons occupationally exposed to cyanoacrylates were more likely to have reversible eye or upper airway irritation than persons who were unexposed.

Our Value: Through a thorough epidemiological investigation and exposure assessment, Cardno ChemRisk was able to reassure the manufacturer and their employees that MCA and ECA exposures in the workplace were not associated with asthma among workers.  This epidemiologic study was the first to investigate the adverse respiratory effects of occupational exposure to either MCA or ECA in which the findings were peer-reviewed and published.