Childhood exposure to high levels of air pollution would lead to smaller and more unhealthy lungs and thereby life-long health problems, say new studies. An ongoing research by the University of Southern California found that those exposed to high levels of air pollution had smaller and more unhealthy lungs by the time they reached adulthood as compared to those exposed to cleaner air. The researchers said that they analysed 12,000 school children to reach these conclusions. Another research conducted by Stanford University researchers recently discovered that breathing dirty air alters gene expression in young children in a way that could predispose them to heart disease as adults. The researchers also pointed out how climate change is certainly playing a role in the new wave of pollution and invited more researchers in the domain.