Effects Of PM_2.5on Congenital Heart Disease In Beijing

Congenital heart disease is a common birth defects in newborns,which has become one of the important public health problems that endanger the physical and mental health of children and reduce the quality of life of the population.In recent years,the impact of exposure to air pollutants during pregnancy on adverse outcomes has attracted increasing attention,among which the relationship between air pollutants and congenital heart disease has become one of the important research topics.Studying the risk of maternal exposure to PM2.5 for overall congenital heart disease,clarifying the effect of exposure to PM2.5 on congenital heart disease subtypes,revealing possible exposure threshold effect about the relationship of "dose-response" between exposure to PM2.5 and congenital heart disease,which has great significance to prevent congenital heart disease and improve the quality of birth population.In this study,pregnant women living in Xicheng district(urban)and Huairou district(rural)in Beijing were studied.The daily average concentration of PM2.5 of Xicheng district and Huairou district were estimated by using single point estimation(SPA)model.Based on the random forest classification model,maternal exposure to PM2.5 during early pregnancy(weeks 3-8 of pregnancy)was used as target predictor and demographic characteristics and exposure to two meteorological factors as control predictors,which mainly evaluated:? the different risks of exposure to PM2.5 average concentration during early pregnancy for congenital heart disease to urban and rural pregnant;?the different risks of exposure to PM2.5 cumulative days during early pregnancy for congenital heart disease to urban and rural pregnant;? the risks of maternal exposure to PM2.5 average concentration during early pregnancy for atrial septal defect and ventricular septal defect.The main conclusion are as follows:There were some similarities and differences in the risk of exposure to PM2.5 average concentration during early pregnancy for congenital heart disease for the urban and rural pregnant women.The risk of congenital heart disease in both regions was about 0.5,when the maternal exposure to PM2.5 average concentration was about 60?g/m3.However,the risk of congenital heart disease was increased obviously after the urban pregnant women exposed to PM2.5 was more than 80?g/m3.Because the rural pregnant women exposed to PM2.5 concentrations was lower than that urban pregnant women,the risk of congenital heart disease was not changed after 80?g/m3.The risk of the urban pregnant exposed to PM2.5 cumulative days during early pregnancy for congenital heart disease was roughly similar compared with the rural pregnant when the pregnant women exposed to PM2.5 cumulative days were in the range of about 0-20 days and there all was a threshold effect in them.The exposure threshold may be about 11 days for the pregnant in urban,while about 17 days for the pregnant in rural and the probability of congenital heart disease was about 0.5.The probability of congenital heart disease in urban and rural all was increased with the exposure to constantly increased cumulative days of PM2.5 when the number of days was below the threshold days;exposure to increased cumulative days of PM2.5 for pregnant in rural was associated with an plummeted risk for congenital heart disease when the number of days exceeded the threshold days,while exposure to increased cumulative days of PM2.5 for pregnant in urban was associated with an slowly lower risk for congenital heart disease.There was a threshold effect on the relationship between maternal exposure to PM2.5 average concentration during early pregnancy and atrial septal defect.The probability of occurrence of atrial septal defect reached the maximum,about 0.55 when exposure concentration may be about 68?g/m3.Maternal exposure to increased concentrations of PM2.5 was associated with an increased risk for atrial septal defect when the exposure concentration was below 68 ?g/m3;exposure to increased concentrations of PM2.5 no longer increased the risk of atrial septal defect when the exposure concentration was higher than 68 ?g/m3.Generally,there was a positive correlation between maternal exposure to the average concentration of PM2.5 during early pregnancy and the occurrence of ventricular septal defect,but the risk of ventricular septal defect occurred with a slight decrease in the inflection point when the exposure concentration may be about 60-80 ?g/m3.This study provides additional evidence for the study of the relationship between exposure to fine particulate matter during pregnancy and congenital heart disease and provides valuable reference for revealing the "dose-response" relationship between fine particulate matter and congenital heart disease and provides a scientific basis for further strengthening the prevention and treatment of congenital heart disease in deepen medical reform and reducing child mortality.In addition,this study also provides the basis to further develop effective environmental laws and regulations and to protect the susceptible population.