When the gases are released, they make this one of the most polluted places on the planet, with La Oroya ranking alongside Chernobyl for environmental devastation, according to a US think-tank, the Blacksmith Institute.
The company is a US corporation, Renco Doe Run. The gases are the product from the main smelter a mile or two down the valley. The high mountains around keep out the cleansing winds, meaning that airborne metals are concentrated in the valley. Neither humans nor nature can escape the company's outpourings of poisons. And, despite evidence that gases have been behind the premature deaths of workers and residents young and old, the business-oriented, pro-US government of President Alan Garcia is too afraid of foreign investors to do anything about it.