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 to 6 years, after controlling for current pollution exposure. Methods Prenatal PAH exposure was measured by personal air monitoring over 48 hrs. 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 to 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 to 6 years. Discerning the differential effects between ETS exposed and ETS nonexposed children requires further study.

Domestic airborne black carbon levels and 8-isoprostane in exhaled breath condensate among children in New York City

“…Polycyclic aromatic hydrocarbons (PAHs) may also be emitted during the combustion processes that generate BC ( i.e. heating) and exposure to these components has been associated with adverse respiratory outcomes (Miller et al, 2004; Rosa et al, 2011). BC may also act as a surrogate for ultrafine particulate matter, which due to its small size can deposit deeper in the lungs, and has been associated with the increased production of oxidative stress species (Alessandrini et al, 2009; Li et al, 2003).…”

Outdoor air pollution and asthma

“…99,100 Even exposures in utero might affect postnatal risk of asthma and asthma exacerbations. 100,101 Low birthweight, which might be associated with narrow airways during early childhood, is a risk factor for symptoms of asthma related to air pollution. 102 …”

“…Some evidence is available to support this expectation. 101,115 What is clear is that polymorphisms of genes ( GSTM1 , GSTP1 , and TNF ) that have been associated with susceptibility to adverse asthma outcomes from exposure to air pollutants have also been associated with increased risks from exposure to secondhand smoke. 116–118 …”

Environmental effects on immune responses in patients with atopy and asthma

“…7,8 Studies from the Columbia Center for Childrens Environmental Health (CCCEH) showed that prenatal exposure to polycyclic aromatic hydrocarbon (PAH), either in association with exposure to second hand smoke, 9,10 or in association with higher cockroach allergen levels, 11 was associated with asthma-related symptoms in children and cockroach allergic sensitization in urban children respectively. African American children in the San Joaquin Valley of California born to mothers who smoked during pregnancy, in association with prenatal exposure to nitrogen dioxide (NO 2 ), PM with median aerodynamic diameter less than 10 microns (PM 10 ) and carbon monoxide (CO), exhibited declines in lung function.…”