Quake helps clear the blackened air over Nepal's brick kilns There are more than 150,000 kilns in India, Bangladesh, Pakistan and Nepal belching out tonnes of soot -- known as black carbon -- a major air pollutant and the second largest contributor to climate change after carbon dioxide. But in one corner of the region, a devastating 2015 earthquake that laid waste to much of Nepal gave the country a chance to clean up its act. IMAGES AND SOUNDBITES