Environmental Pollution and the Developing Lung.

In this review, we discuss the impact of environmental tobacco smoke and particulate and gaseous air pollutants derived from fossil fuel combustion on a particularly vulnerable population, infants and children. Indoor and outdoor air pollutants exacerbate chronic respiratory diseases and lower respiratory tract infections. However, there is an even more alarming impact of antenatal air pollution exposures. There are several reports in rodents and monkeys that maternal exposure to tobacco smoke or fossil fuel-generated air pollutants causes in utero growth retardation, lung remodeling, and immune cell activation which increase the risk for asthma or the risk of morbidity with respiratory infections. Importantly, epidemiologic studies confirm that maternal exposure to air pollutants decreases lung function in infants and children which may persist to young adulthood. Thus, environmental air pollutants contribute to childhood origins of chronic obstructive lung disease by changing the capacity for normal lung development and repair, by promoting early lung inflammation which increases the susceptibility to pollution-triggered symptomatic lung disease in adulthood, and by limiting the capacity for later adaptive/repair responses to environmental and infectious insults.