Mercury contamination in Grassy Narrows

From 1962 to 1970, an uncontrolled mercury discharge of between 9,000 kilograms (20,000 lb) and 11,000 kilograms (24,000 lb) from the Dryden Mill's chloralkali plant in Dryden into the headwaters of the Wabigoon River in the Kenora District of Northwestern Ontario occurred. It was described as "one of the worst cases of environmental poisoning in Canadian history." The contamination poisoned many people in the Grassy Narrows First Nation and Whitedog First Nation communities.

Source: Wikipedia — Mercury contamination in Grassy Narrows (CC BY-SA 4.0)