HealthDay News — The cumulative effect of multiple indoor air pollutant exposures prenatally and early in life may influence allergies in 2-year-olds, according to a study published online Nov. 22 in the Annals of Allergy, Asthma & Immunology.
Mallory J. Gallant, from Queen’s University in Kingston, Ontario, Canada, and colleagues followed 108 mother-child pairs enrolled in the Kingston Allergy Birth Cohort from birth to 2 years of age to evaluate the effect of prenatal and early-life exposure to seven air-polluting factors on allergic sensitization at 2 years of age. Assessments of exposure to air fresheners, candles, mold, cats, dogs, carpet, and environmental tobacco smoke (ETS) were conducted prenatally and at 6 months, 1 year, and 2 years of age.
The researchers found that exposure to candles during the prenatal window, cats at 6 months, and ETS at 2 years significantly increased the odds of a positive skin prick test (SPT; odds ratios for candles, cats, and ETS: 5.096, 4.267, and 3.78, respectively). Children with a positive SPT had significantly more exposures compared with children with negative SPTs. With an increasing total number of exposures, the percentage of SPT-positive children increased.
“Children breathe more frequently per minute than adults, and mostly breathe through their mouths,” a coauthor said in a statement. “These differences could allow for air pollutants to penetrate more deeply into the lungs and at higher concentrations, making children more vulnerable to air pollutants.”
One author disclosed financial ties to the pharmaceutical industry.