Asthma and exposure to quaternary ammonium compounds in healthcare settings

An increased incidence of asthma was reported among professionals working in healthcare settings. However the role of the quaternary ammonium compounds (QUATS) is not yet clear in the induction or aggravation of these symptoms. Aim: To analyze, among health care settings professionals, the influence of QUATS and irritants exposure on the occurrence of respiratory symptoms including asthma. Methodology: All workers with more than 6 months of seniority working in 7 healthcare facilities were requested. The survey included a self-administered questionnaire, physical examination, spirometry and blood sample. Occupational exposure assessment was made by expert judgment and workplace studies. Results: 543 workers participated. QUATS occupational exposure was specified for 444 workers: 335 exposed and 109 non exposed. The QUATS exposed workers were 50% nurses, 22% auxiliary nurses, 19% cleaners. The frequency of all variables defining asthma was significantly higher among the QUATS exposed workers: 18.3% vs 5.5% for ever asthma, 14.4% vs 2.7% for asthma confirmed by a physician, 6.7% vs 1. 8% for asthma in the last 12 months, 7.9% vs 1.8% for new onset asthma after entry into healthcare profession. In multiple analysis, after adjustment 2 variables, atopy and quats exposure were associated with physician diagnosed asthma (RR=5.5 [2.7-10.9] p<10-3) and 4.2 [1.3-13.6] p < 0.01, respectively. The same factors were found for rhinitis. Disinfection of surfaces was significantly associated with asthma RR=5.8 (1.7-19.3). Conclusion: QUATS exposure increased the risk of asthma, the high-risk tasks being the disinfection of surfaces, the preparation of soaking solutions, the dilution of products and the use of sprays.