Lake Baikal. Lake Baikal holds one fifth of Earth's fresh water supply. Nickolay Ryutin

By Katia Moskvitch Science reporter, BBC News The UN may remove the world’s deepest and oldest lake from the World Heritage list because of concerns over pollution by a Russian pulp and paper mill. Lake Baikal holds one fifth of the world’s fresh water and is home to many unique plants and animals. At its 34th session about to kick off in Brazil, the World Heritage Committee will discuss the effect of the plant’s wastewaters on the unique ecosystem. Baikal was awarded World Heritage Site status in 1996. A representative from the United Nations Educational, Scientific and Cultural Organization (Unesco) told BBC News that as a result of the mill, the lake may end up on the list of World Heritage in danger – or get struck off it altogether. Ecologists say the mill affects more than 50% of Baikal’s ecosystem. … Ecologists say the mill has been spewing thousands of tonnes of dioxins and other harmful by-products into Baikal. … Marina Rikhvanova, a biologist and renowned ecologist from Irkutsk environmental group, The Baikal Environmental Wave, has been fighting the mill for years. For her efforts to preserve Baikal, she received the prestigious Goldman environmental award. She told BBC News that the contaminated area – the so-called stain from the mill – moves further and further towards the north. “Near the mill, up to 80% of epicshura dies – a unique Baikal crustacean that cleans the lake. Molluscs get genetic mutations at the chromosome level and fish become disoriented and unable to find food or go to their spawning grounds,” she said. … For now though, local fishermen try to move further away from the plant – as in its vicinity, they say fish have become scarce.

UN may strike Baikal off World Heritage list