Objective To evaluate the acute effects of exposure to cleaning products on lung function of female cleaning workers.

Methods A panel study including 21 female cleaners with persistent asthma symptoms was nested within a case-control study. Participants recorded the use of cleaning products in 2-week diaries resulting in 312 person-days. All participants were trained to perform lung function testing using a PIKO-1^® device to measure FEV₁ (mL) and PEF (L/min) three times per day (in the morning after waking-up, at midday and in the evening before going to sleep). Associations between cleaning products and FEV₁ and PEF in the evening of the same day of exposure, in the morning next day and FEV₁ and PEF’s diurnal variation (amplitude over daily mean) were evaluated using linear mixed regression analysis. All models included a random term for individual and were adjusted for age, height, number of cigarettes smoked, respiratory infection, and respiratory medication. The reference category for all comparisons was “No use of cleaning products”.

Results Evening FEV₁ and PEF were 8.7 ml (95% confidence interval (CI) 1.7–15.7) and 36.9 l/min (CI 4.3–69.5), lower on days when three or more cleaning sprays were used, respectively (p-values for trend: 0.054 for FEV₁ and 0.053 for PEF). Evening FEV₁ significantly decreased after exposure to hydrochloric acid (30.8 ml) and solvents (37.6 ml). Diurnal variation in FEV₁ increased on days using ammonia (12.7%), lime-scale removers (9.3%), air-fresheners (7.2%) and multiuse products (6.8%). Diurnal variation in PEF increased on days using ammonia (17.0%), lime-scale removers (13.0%), powder detergents (11.4%), and air-fresheners (8.6%). Morning FEV₁ decreased on days following the use of solvents (53.0; 36.3–69.6), hydrochloric acid (26.3 ml; CI: 14.7–37.9), powder detergents (26.1; 16.7–35.6), and degreasers (19.1; 12.6–25.7).

Conclusions Acute changes in lung function suggest that the use of specific cleaning products may exacerbate pre-existing asthma.