Does the emissions testing of our cars help reduce respiratory diseases like childhood asthma? Well according to Dr. Kenneth Green of Canada’s Fraser Institute, the link between emissions testing, clean air, and childhood asthma is a nebulous one at best. Comments Green: “Studies show that car emission testing fails to find the small number of broken vehicles that create most of the air pollution from cars.  Car testing also doesn’t offer much health benefit, since air pollution is unlikely as a cause of asthma.  Even as air pollution levels in North America has fallen, asthma rates have risen.  Meanwhile, asthma rates have risen in Australia and New Zealand, despite very low levels of air pollution, while asthma rates are low in countries like Indonesia and Mexico, which have very high levels of air pollution.”