Occupational exposures and fluorescent oxidation products in 723 adults of the EGEA study

Occupational exposures to cleaning/disinfectant products are associated with asthma but the underlying biological mechanisms are still unclear. The aim was to study the associations between specific occupational exposures and the level of fluorescent oxidation products (FlOPs), a useful global marker of oxidative stress, in adults without asthma from the Epidemiological study on the Genetics and Environment of Asthma (EGEA). Occupational exposures were assessed by (1) an asthma job exposure matrix (JEM, http://cesp.vjf.inserm.fr/asthmajem/), and (2) a questionnaire on specific hazards followed by an expert assessment in hospital workers. FlOPs were measured in plasma by spectrofluorometer. Associations between occupational exposures and FlOPs level were evaluated separately in men (n=328) and women (n=395). Geometric mean (Q1-Q3) of FlOPs levels in all adults were 94.4 (81.9-108.1) RFU/mL. As expected, FlOPs levels increased with age (p0.0001), were higher in women (95.5 (82.3-109) vs. 93.0 (80.6-105), p=0.06), and in ex- and current smokers both in men and women (p0.01). Current exposure to cleaning products assessed by expertise was associated with higher FlOPS levels (115 (86.6-115) n=10 vs. 91.3 (80.3-102) n=180 p=0.004 in men; 101 (87.0-110) n=51 vs. 95.1 (81.9-109) n=289 p=0.08 in women) adjusted for age and smoking. In men, current exposure to any low molecular weight agents assessed by asthma JEM or expertise was also associated with higher FlOPS levels (106 (88.7-117) n=35 vs. 91.3 (80.3-102) n=180, p=0.002). Results suggest that oxidative stress may be one of the biological mechanisms to explain the role of occupational exposures to irritant cleaning products in asthma.