Current use of room disinfectants and allergic symptoms at the age of 4 years

To the Editor: Epidemiologic studies suggest an association of occupational domestic cleaning with asthma.1,2 More recently, a correlation of nonprofessional use of cleaning sprays with adult asthma has also been reported for private households.3 In this study application of commonly used cleaning and air-refreshing sprays was found to be a major risk factor for asthma, but the relevance of these findings for children remains to be understood. Because of their small airway diameters, young children are particularly susceptible to respiratory symptoms. To this end, we performed an observational study in 4-year-old offspring from pregnant women participating in a multicenter, randomized, double-blind, placebo-controlled clinical trial described in detail elsewhere.4 Briefly, the effects of increased intakes of a fish oil preparation (0.5 g of docosahexaenoic acid and 0.15 g of eicosapentaenoic acid), 400 μg of 5-methyl-tetrahydrofolate, both, or placebo from the 22nd week of gestation until delivery and birth outcomes were assessed in the main trial. [...]a selection bias with respect to allergic diseases and use of room disinfectants would not be expected.