Diego J Lopez, PhD and colleagues from the University of Melbourne sought to determine the role of air pollution in the development of food allergies and eczema. The results of their study were recently published in the Journal of Allergy and Clinical Immunology.
HealthNuts — the worlds first longitudinal, population-based study of food allergy — recruited a population-based sample of 1-year-old infants who were followed up at ages 4, 6, and 10 years.
Using geocoded residential addresses, they assigned annual averages for two common air pollutants — fine particulate matter and nitrogen dioxide (NO2) — to each HealthNuts participant as well as their status for food allergies and eczema. Oral food challenges to peanut, egg, and sesame were used to indicate food allergy, and eczema was defined by parent report. Multilevel logistic regression models were fitted, and estimates were reported as adjusted odds ratios.
The researchers found the prevalence of peanut allergy at ages 1 and 4 years was higher for those exposed to a high concentration of NO2 at age 1 year, with adjusted odds ratios, 2.21 and 2.29, respectively, meaning their odds of them developing the disease were 2.21 and 2.29 times than those not exposed. Peanut allergy in 4, 6, and 10-year-olds had an adjusted odds ratio of 1.27, 1.27, and 1.46 in areas where fine particulate matter was high.
There was little evidence of associations with eczema or egg allergy.
They concluded that early-life exposure to fine particulate matter and NO2 was associated with peanut allergy prevalence and persistence and that policies aiming at reducing air pollution could potentially reduce presence and persistence of peanut allergy.
