Air pollution is a serious problem in China. Exposure to ambient air pollution has been linked to numerous adverse health outcomes, including cardiovascular disease, respiratory disease, and adverse birth outcome. The study of the effects of maternal exposure to air pollution on birth defects is an emerging field and lacks consistent observational results. Moreover, there is no previous study conducted in Asia investigating the relationship between congenital heart defects (CHD), the most common birth defects, with air pollution, even though the prevalence of CHD is highest in Asia. One of the most critical challenges for this type of study is the lack of complete monitoring data in developing countries. In order to tackle this problem, some previous studies explored the application of satellite data on air pollution estimation. Therefore, in this present study, we propose to use satellite data to estimate maternal exposure in our study area and further investigate the association of maternal exposure to congenital heart defects.
Our study area is a city called Lanzhou, located in Northwest China. It is the capital and largest city of Gansu Province, with 5058 mile2 in area and 3.6 million residences. Our study population is 10,542 women who gave birth from 2010-2012. We have monitoring data for PM10, SO2, and NO22 from only 4 monitors, which are all located in the city center. Using inverse distance weighting, we were able to give exposure estimation for the study subjects and found significantly positive associations. But all the monitors concentrate in the city center. Its area accounts for less than 1/4 of that of the whole city. So we want to use satellite data to improve the accuracy of maternal exposure estimation. Satellite data will first be calibrated by the ground monitoring data. And then the established prediction model will be used to predict the air pollution level at the locations where the subjects live. But the specific plan about how to use satellite is still being developed.