MOUNTAIN breezes might not be as fresh as we imagine, at least in some parts of the world. Pesticides used on banana, coffee and rice plantations are contaminating remote Central American tropical rainforests by hitching a ride on air currents as they sweep up mountainsides. This may help to explain why mountain amphibians are in severe decline.
Frank Wania from the University of Toronto, Canada, and colleagues measured pesticide levels in soil and air at 23 sites across Costa Rica. They found levels in remote mountain areas in the Braulio Carrillo National Park were around 10 times those in the lowlands. Such areas were thought to be too far from plantations to be affected.
The team's computer model shows that a mountain breeze is transporting the pesticides tens of kilometres (Environmental Science & Technology, DOI: 10.1021/es0622709). The pesticide-laden air from the lowlands cools as it hits the mountains and rises. ...
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