Bagini JM, LeMasters GK, Ryan PH, et al. Pediatr Allergy Immunol. 2006:17:278–284 PURPOSE OF THE STUDY. To examine the impact of environmental tobacco smoke (ETS) and visible mold exposure on the development of allergic rhinitis, rhinitis, and upper respiratory infection (URI) in early infancy. STUDY POPULATION. Six hundred thirty-three infants ≥35 weeks’ gestation with at least 1 parent who had 1 of 12 selected allergy symptoms and a positive skin-prick–test result to at least 1 of 15 aeroallergens. METHODS. The child's birth certificate and a questionnaire format were used to collect demographic data and information on family smoking habits, family health history, pet ownership, day care attendance, breastfeeding, and the infants’ respiratory health history from birth to the time of enrollment. Parents were asked to complete monthly diaries to collect information on their child's upper respiratory symptoms. They must have completed 1 diary before the child's 12-month clinical examination. Allergic rhinitis was defined as having rhinitis symptoms not associated with a cold or chest infection at least once on any diary and a positive skin-prick–test result to ≥1 aeroallergen at the 12-month visit. Study personnel examined the home for mold exposure within 3 weeks of study enrollment. RESULTS. Infants were nearly 3 times more likely to have allergic rhinitis at 12 months of age (odds ratio [OR]: 2.7; 95% confidence interval [CI]: 1.04–6.8) and twice as likely to have rhinitis (OR: 1.9; 95% CI: 1.1–3.2) when exposed to ≥20 cigarettes per day. Infants were 5 times more likely (OR: 5.1; 95% CI: 2.2–12) to have frequent URIs when exposed to high mold levels. Having older siblings was protective for development of rhinitis and allergic rhinitis at age 1. CONCLUSIONS. ETS exposure is associated with rhinitis and allergic rhinitis in infants. Mold may be a stronger risk factor for URI than ETS. REVIEWER COMMENTS. This is one of very few studies to have examined the relevance of home exposures in the first year of life and demonstrated that early environmental exposures likely play a significant role in respiratory health outcomes in infancy. One weakness of the study was the fact that ETS exposure and URI and rhinitis symptoms were collected by parental report and may be subject to significant recall bias or erroneous reporting. Nevertheless, these findings support the need for further research in the areas of early environmental-exposure interventions and the role of gene-environment interactions that affect respiratory health outcomes.