Dam break in Brazil had released toxic wastes into waterways, says UN

Mud released following a massive dam failure at an iron ore mine in Brazil earlier in the month contained ‘high levels of toxic heavy metals and other toxic chemicals’, according to United Nations Office of the High Commissioner for Human Rights.

Around 55 million m3 of tailings, waste from iron-ore mines got released into the Rio Doce river following the accident, which occurred on 5 November at the Samarco Fundão dam in Minas Gerais.

The UN agency had prepared a special report which cites the presence of toxic materials in the mud that has affected communities and caused pollution to hundreds of miles of waterways in southeast parts of the country.

Prepared by UN rapporteurs John Knox and Baskut Tuncak, the report cited new evidences which contradict the statements released by the Brazilian government and the mining companies.

Both Samarco, which was the mine operator at the site of the rupture, and its co-owner BHP Billiton had stated that water and mineral wastes released from the dam are non-toxic.

BHP Billiton said: "The tailings that entered the Rio Doce were comprised of clay and silt material from the washing and processing of earth containing iron ore, which is naturally abundant in the region.

"Based on available data, the tailings are chemically stable. They will not change chemical composition in water and will behave in the environment like normal soils in the catchment."

Around 12 people had died due to the sludge overflow in the nearby towns following the dam burst and at least 11 people are still missing, reports The Wall Street Journal.