title: Prenatal exposure to polycyclic aromatic hydrocarbons, environmental tobacco smoke and asthma.
abstract: BACKGROUND
  Previously, we reported that prenatal exposures to polycyclic aromatic hydrocarbons (PAH) and postnatal environmental tobacco smoke (ETS) in combination were associated with respiratory symptoms at ages 1 and 2 years. Here, we hypothesized that children exposed to both prenatal PAH and ETS may be at greater risk of asthma and seroatopy at ages 5-6 years, after controlling for current pollution exposure.
  
  
  METHODS
  Prenatal PAH exposure was measured by personal air monitoring over 48 h. ETS exposure, respiratory symptoms and asthma at ages 5-6 years were assessed through questionnaire. Immunoglobulin (Ig) E was measured by Immunocap.
  
  
  RESULTS
  A significant interaction between prenatal PAH and prenatal (but not postnatal) ETS exposure on asthma (p < 0.05), but not IgE, was detected. Among children exposed to prenatal ETS, a positive nonsignificant association was found between prenatal PAH exposure and asthma (OR 1.96, 95% CI [0.95-4.05]). Among children without exposure to prenatal ETS, a negative nonsignificant association was found between prenatal PAH exposure and asthma (OR 0.65, 95% CI [0.41-1.01]). Prenatal PAH exposure was not associated with asthma or IgE at age 5-6 years.
  
  
  CONCLUSIONS
  Combined prenatal exposure to PAH and ETS appears to be associated with asthma but not seroatopy at age 5-6. Exposure to PAH alone does not appear associated with either asthma or seroatopy at age 5-6 years. Discerning the differential effects between ETS exposed and ETS nonexposed children requires further study.
authors.affiliation: Division of Pulmonary, Allergy, Critical Care Medicine, Department of Medicine, Columbia University College of Physicians and Surgeons, NY 10032, USA. mr2805@columbia.edu
authors.forename: Maria José
authors.initials: MJ
authors.lastname: Rosa
authors.forename: Kyung Hwa
authors.initials: KH
authors.lastname: Jung
authors.forename: Matthew S
authors.initials: MS
authors.lastname: Perzanowski
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Kelvin
authors.forename: Katherine W
authors.initials: KW
authors.lastname: Darling
authors.forename: David E
authors.initials: DE
authors.lastname: Camann
authors.forename: Steven N
authors.initials: SN
authors.lastname: Chillrud
authors.forename: Robin M
authors.initials: RM
authors.lastname: Whyatt
authors.forename: Patrick L
authors.initials: PL
authors.lastname: Kinney
authors.forename: Frederica P
authors.initials: FP
authors.lastname: Perera
authors.forename: Rachel L
authors.initials: RL
authors.lastname: Miller
mesh_terms: D001249:Asthma / Q000139:chemically induced / Q000453:epidemiology / Q000209:etiology*; D002648:Child; D002675:Child, Preschool; D004781:Environmental Exposure / Q000009:adverse effects*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D011084:Polycyclic Aromatic Hydrocarbons / Q000009:adverse effects*; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D011795:Surveys and Questionnaires; D014028:Tobacco Smoke Pollution / Q000009:adverse effects*
chemical_list: D011084:Polycyclic Aromatic Hydrocarbons; D014028:Tobacco Smoke Pollution