Women who clean using chemicals at home and at work show faster declines in some lung function, according to a new study spanning 20 years.

The women – but not the men – who clean their homes or workplaces showed decreased lung function in exhalation tests, according to the paper in the American Journal of Respiratory and Critical Care Medicine. The accelerated lung decline was “comparable to smoking somewhat less than 20 pack-years,” they conclude.

The underlying reason, they speculate, is the inhalation of minute traces of the toxic cleaning agents over a long period of time, irritating the mucous membranes, causing major changes in the airways and breathing. 

“The take-home message of this study is that in the long run cleaning chemicals very likely cause rather substantial damage to your lungs,” said Øistein Svanes, the lead author, a doctoral student at the University of Bergen in Norway.

The population of 6,230 participants was examined three times over 20 years, as part of the European Community Respiratory Health Survey. Fifty-three percent of the respondents were women; the group’s mean age was 34 at the beginning of the study, and 54 at its completion.

Adjusted factors were smoking, body-mass index, and socioeconomic status (age at attained education was a proxy used for this factor).

The participants all reported how often they had cleaned, and used chemicals in doing so. Some 85 percent of the females reported being the main cleaner at home, while only 46.5 percent of the men reported the same. Fewer were occupational cleaners – just under nine percent of the women and under two percent of the men reported being employed as such.

The group took lung function tests: the maximum forced vital capacity assessment (FVC) measured how much air they could exhale at once, and the maximum forced expired volume in one second (FEV1) examination measured just the first second of forced air.

The women who cleaned at home declined 3.6 ml per year faster in FEV1, and 4.3 ml faster in FVC. The women who cleaned at work declined faster still – 3.9 ml per year in FEV1, and 7.1 ml in FVC.

Asthma was also more prevalent among those who cleaned at home or work, as opposed to those who did not clean, they report (12.3 percent, 13.7 percent, and 9.6 percent, respectively).

However, the ratio between FEV1 to FVC – which is a key metric in determining chronic obstructive pulmonary disease (COPD) – did not decline more rapidly in the women who cleaned.

The men who cleaned, in the meantime, did not experience greater decline in the exhale tests than those who did not clean.

The harshest chemicals are not needed for most jobs, contends Svanes, the lead author of the paper.

“These chemicals are usually unnecessary; microfiber cloths and water are more than enough for most purposes,” he said.