Interaction effects of breastfeeding and air pollution on respiratory diseases and symptoms in children

Objective To investigate the interaction effects of breastfeeding and air pollutants on children's respiratory diseases and symptoms. Methods The study was a cross-sectional study of respiratory health effects of exposure to ambient air pollutants.Based on the results of air pollution measurements taken between 2006and 2008,the seven cities of Shenyang,Dalian,Anshan,Fushun,Benxi,Liaoyang and Yingkou in Liaoning province were selected as study sites. Results A total of 10 822 children were investigated in the study,a total of 9 318 questionnaires were returned,the response rate was 86.1%.Daily average concentration of four pollutants PM10,SO2,NO2,O3 were analyzed,daily average concentration of PM10,SO2 exceeded the national standards and day average concentrations of PM10,SO2 exceed international standards in all of the 25 districts,daily average concentration of NO2 exceed the national standard in 36% districts.There were 7 319 breastfed children and 1 999 non-breastfed children,and the breastfed boys were more than girls(P0.05);non-breastfed children compared with breastfed children,atmospheric pollutants PM10,SO2,NO2,O3per one unit increased in children with persistent cough,the risk of continued sputum showed an increasing trend(P0.05).Breastfeeding and atmospheric pollutants PM10,SO2,NO2,O3on wheezing of children existed statistically significant interaction(P0.20). Conclusion This study provides evidence that there is a significant interaction effects between breastfeeding and air pollutants on some respiratory diseases and symptoms in children.