“Prenatal Ambient Air Pollution and Birth Weight”


In recent years, traffic related air pollution has been considered an important risk factor
for adverse reproductive health effects. Prenatal exposure to nitrogen dioxide has been associated with low birth weight, and preterm birth. Infants with low birth weight are at higher risk of mortality and morbidity, and impaired cognitive development compared to infants with higher birth weight. The mechanisms responsible for fetal growth
restriction due to air pollution are largely unknown, and this study tries to clarify this question.

The placenta plays a unique role in gases, nutrient and waste transfer between the mother
and developing child. The placenta requires energy to maintain its function and this energy provision is regulated by mitochondrial function of placenta cells. Mitochondria, the energy producers of the cells, are particularly sensitive to
environmental toxicants due to their lack of repair capacity. Air pollution could lead to mitochondrial damage.

This study is based on two European birth cohorts, INMA in Spain, and ENVIRONAGE in Belgium. It aimed to assess if mitochondrial damage due to air pollution could explain low birth weight.

376 mother-new born pair in Spain and 550 in Belgium participated. The data have shown that a high prenatal exposure to pollution probably could lead in a mitochondrial damage and this resulting in a low birth weight.

Considering the high levels of air pollution in urban areas, which are increasing worldwide, this study indicates the relevance of further exploring these results linking early air pollution exposure and complications at birth.

Reference: Clemente DB, Casas M, Vilahur N, Begiristain H, Bustamante M, Carsin AE, Fernández MF, Fierens F, Gyselaers W, Iñiguez C, Janssen BG, Lefebvre W, Llop S, Olea N, Pedersen M, Pieters N, Santa Marina L, Souto A, Tardón A, Vanpoucke C, Vrijheid M, Sunyer J, Nawrot TS. Prenatal Ambient Air Pollution, Placental Mitochondrial DNA Content, and Birth Weight in the INMA (Spain) and ENVIRONAGE (Belgium) Birth Cohorts. Environ Health Perspect. 2016 May;124(5):659-65.