Abstracts: ISEE 21st Annual Conference, Dublin, Ireland, August 25–29, 2009: Poster Presentations
To study DNA methylation, exhaled nitric oxide (FeNO), lung function (FEV1) in children with respiratory symptoms exposed to industrial air pollution.
A panel study of 39 children aged 8–11 years followed on 2007/12–2008/4 was conducted in Valle-del-Mela (Sicily-Italy), a High Risk Area (55504 inhabitants) with oil refineries and energy plants. Symptomatic children were screened by modified ISAAC questionnaire (2506, 89.5% responders). The 39 selected children were divided into 9 groups matched by school, monitored for 7 consecutive days. DNA Methylation was measured on nasal mucosa cells collected by swab, twice per subject on day fourth and seventh of the same week. Personal PM2.5 active, NO2, SO2 passive sampling were done on one child witness of a 4-child group. Ambient PM2.5 monitor, meteo station, passive NO2 SO2 samplers in 21 schoolyards were used. Diaries filled in by parents recorded symptoms, therapy, indoor sources. Data were analyzed with mixed models controlling for confounders.
Average daily ambient PM2.5 was 23.0 μg/m3, weekly ambient SO2 over 20 μg/m3 in three locations. Average daily (90 percentile) personal PM2.5 was 44.5 (86.6), SO2 17.7 (32.8). Effect measures were expressed for 10 μg/m3 increase of pollutant concentration.
We found FEV1 reduction −4.3% (90% Confidence Interval −6.1; −2.6%) for SO2 lag2 (P < 0.01), FeNO increment 10.8% (3.2–18.4%) for SO2 lag01 (P = 0.022); a decrease −1.0% of global DNA Methylation (Alu elements 90% CI −2.0; −0.6%) and −4.1% of iNOS (−7.8; −0.4%) for SO2 lag12; −1.8% (−3.0; −0.6%) of iNOS for PM2.5 lag12. DNA Methylation of interleukin 6 position was reduced when FEV1 was below median (P = 0.028) and when FeNO was below median (P = 0.048); consistently iNOS was reduced (P < 0.001).
Short-term exposure to industrial pollutants was associated with changes in DNA methylation, bronchial inflammation and lung function in children with respiratory symptoms.