The Ministry of Environment, Conservation and Parks issued an advisory not to consume any Smelts caught south of Batchewana Bay to the St. Mary’s River headwaters (the Goulais Bay area) due to a toxin which has recently been detected in them called Toxaphene. Read the full story by Sault Online.
Great Lakes Commission
https://www.glc.org/dailynews/20210406-smelts