Prenatal exposure to traffic-related air pollution and risk of congenital diseases in South Korea. - GreenMedInfo Summary

BACKGROUND: Previous studies have suggested links between exposure to ambient air pollutants and increased risk of congenital heart defects. However, few studies have investigated the association between other congenital diseases and traffic-related air pollution. In this study, we assessed the relationship between prenatal exposure to fine particulate matter (PM) and nitrogen dioxide (NO) with congenital diseases in South Korea.

METHODS: Patients with one or more congenital diseases and a control group of patients with non-infective gastroenteritis and colitis with a case:control ratio of 1:3 were obtained from the National Health Insurance Service data for 2008-2013 in South Korea. We estimated the associations of PMand NOexposures with congenital diseases using generalized estimation equations after controlling for covariates.

RESULTS: Maternal PMexposure during the first and second trimester showed positive associations with overall congenital diseases, with changes of 14.7% (95% confidence intervals (CI), 9.3%, 20.3%) and 16.2% (95% CI, 11.0%, 21.7%), respectively, per 11.1 μg/mand 10.2 μg/mincrease of PMinterquartile range (IQR). Similarly, NOexposure during the first and second trimester was associated with increased numbers of overall congenital anomalies, with 8.2% (95% CI, 4.2%, 12.3%) and 15.6% (95% CI, 9.3%, 22.2%) more cases, respectively, per 10.6 ppb increase of NO. We found that maternal PMexposure during the first and second trimesters of pregnancy was significantly associated with increased risk of specific congenital diseases, including subtypes affecting the circulatory, genitourinary, and musculoskeletal system. However, no significant associations were observed during the third trimester. Maternal NOexposure across the entire pregnancy was associated with malformations of the musculoskeletal system.

CONCLUSIONS: Our study identified significant links between in utero exposure to PMand NOand certain congenital diseases, and suggests that stricter controls on PMand NOconcentrations are required.