Brick kiln emissions affect crop yields, study finds
Hydrogen fluoride emissions from brick kilns have been found to damage trees and crops in new studies conducted by an international team of scientists in the Peshawar area of northern Pakistan. Peshawar has 450 brick kilns and hydrogen fluoride is also released by factories making aluminum, ceramics, and phosphate fertilizers.
Reporting their findings in the February issue of Environmental Pollution, the scientists from the Netherlands, Pakistan and the UK said despite the potential of high fluoride emissions to damage to crops, "the impact of these brick kilns on agricultural production and farmers' livelihoods in Asia is poorly understood".
The scientists looked out for visible signs of injury to leaves, such as burnt-looking tips, as well as the amount of fluorides and sulfur in the leaves of apricot, plum and mango trees. They also interviewed local farmers about their observations of tree injury in orchards.