Soiled earth

In 1981-82, some farmers from Hoshiarpur and Nawanshehar districts approached scientists at Punjab Agricultural University (PAU), Ludhiana. Their wheat crops had turned white, animals were diseased with healthy cattle dying within months of purchase.

Soil analysis indicated selenium (Se) levels above toxic limits in an area of 1,000 hectares of land. Se is a naturally occurring trace element, essential for animal and human health, but the gap between requirement and excess is narrow. Soils containing 0.5 microgramme (