RESUMEN
INTRODUCTION: Few investigations have related objective assessments of indoor air pollutants to respiratory health in farmers, in spite of the many rural environmental hazards to which they are exposed. Chemical air pollution has been particularly neglected. OBJECTIVE: We investigated the relationships of indoor exposure to particulate matter (PM) and volatile organic compounds (VOCs) to respiratory health in farmers. METHODS: Nineteen VOCs (5 families) and PM (from ultrafine to total suspended particles (TSP)) were objectively assessed in dwellings and workplaces in 109 French farmers during a week. To take into account multiple exposures, scores of exposure were computed for total VOCs and VOCs families. Individuals filled a standardized questionnaire and underwent spirometry with bronchodilation test. RESULTS: On average, VOCs concentrations were higher in dwellings than in workplaces. The reverse was observed for PM. When considering the mean concentrations of air pollutants for the whole farm (dwellings + workplaces), asthma (9.3%) was positively associated with elevated exposure to benzene (adjusted odds-ratio (ORa) = 6.64, 95%CI: 1.56-28.27), trichloroethylene (4.80, 1.00-23.30) and halogenated hydrocarbons score (2.9, 95% 1.3-6.8). Early airway obstruction (FEF25-75 < 80%, with normal FEV1 and FVC and FEV/FVC ≥ 70%) (29.8%) was related to elevated exposure to 2-butoxyetylacetate (11.49, 1.55-85.37) and glycol ethers score (2.0; 1.0-4.1) in the whole farm and to PM2.5 (ORa = 5.26, 95% CI: 1.09-25.28) in the granary/stable. The risk of Chronic Obstructive Pulmonary Diseases (FEV/FVC < 70%) (COPD) (4.26%) was found to be larger with elevated exposure to aldehydes (OR = 3.95, 1.09-14.26). CONCLUSION: Indoor chemical air pollution is detrimental to farmers' respiratory health. More epidemiological investigations with detailed exposure assessments and clinical measures of respiratory effects are needed in rural settings to corroborate these findings.
RESUMEN
Although French farmers smoke less on average than individuals from the general population, they suffer more from COPD. Exposure to biological and chemical air pollutants in the farm may be the cause of these higher COPD rates. This study investigates the role of bio-contaminants, including the relationship of exposure to volatile organic compounds (VOCs) and fine particulate matter (of diameter of 2.5 µm [PM2.5]) objectively measured in the farm settings (dwellings and workplaces) to serum cytokines involved in COPD, in a sample of 72 farmers from 50 farms in the Auvergne region, France. Mean concentrations of VOCs were highest inside the home, while levels of PM2.5 were highest in workplaces (stables and granaries). After adjusting for confounders, high exposure to PM2.5 was significantly associated with a decreased level of serum cytokines (among others, IL13: ß: -0.94, CI: -1.5 to -0.2, P-value =0.004; IL8: ß: -0.82, CI: -1.4 to -0.2, P-value =0.005) and high exposure to VOCs according to a VOC global score with a decreased IL13 level (ß: -0.5, CI: -0.9 to -0.1, P-value =0.01). Moreover, respiratory symptoms and diseases, including COPD, were associated with a decreased level of serum cytokines significantly in the case of IL5. An alteration of immune response balance in terms of cytokine levels in relation to indoor chemical air pollution exposure may contribute to respiratory health impairment in farmers.
