Prenatal exposure to chemical products, early indoor environment and wheezing and eczema in infancy

Abstract

Home environment has been linked to childhood allergies and asthma, as have been several household chemical products, but evidence on their health effects in early life is scarce. We aimed to explore associations of prenatal exposure to chemical substances and indoor environmental exposures in the first months of life with wheezing and eczema in infancy. The study included 4422 singletons from the Italian NINFEA birth cohort. Maternal occupational or non-occupational exposure to chemical products in the third trimester of pregnancy and indoor environment in the first 6 months of life were ascertained from the questionnaire completed by mothers at 6 months of age. Information on the occurrence of wheezing and eczema between 6 and 18 months of age was obtained from the questionnaire completed 18 months after delivery. Analyses were adjusted for maternal age, history of asthma and atopy, educational level, nationality, smoking during pregnancy and parity. Infant wheezing and eczema prevalence were 17.6% and 16.3%, respectively. The most commonly used chemical products in the third trimester were bleach (39.8%), disinfectants (39.4%) and window-cleaning products (35.4%). Maternal use of insecticides/pesticides was associated with wheezing (adjusted OR: 1.44; 95%CI: 1.02-2.03), while use of bleach (1.30; 1.11-1.53), paint remover (2.12; 1.07-4.20) and adhesives/mastics (1.47; 1.05-2.06) was associated with infant eczema. Analyses restricted to frequent use (≥1 per week) revealed additional associations between window-cleaning products and eczema, and wall paint and wheezing. Day-care attendance, urban living area, dampness/mould and cooking with gas in the first 6 months of life were positively associated with infant wheezing. Of these exposures, only urban living area was associated with eczema (0.72; 0.59-0.89). These data suggest that several environmental exposures during a critical developmental period are involved in the onset of early wheezing and eczema.