Montana’s Fish Consumption Advisory Board, which is made up of representatives from the Departments of Environmental Quality and Public Health & Human Services and Fish, Wildlife & Parks, announced Tuesday that multiple fish species tested at high levels for a class of chemicals called polycyclic aromatic hydrocarbons.
The sampled fish were longnose suckers, shorthead redhorse, rainbow trout, brown trout and mountain whitefish.
According to the Centers for Disease Control and Prevention, there are over one hundred PAHs, and some are known to cause cancer and other health impacts in animals.
Spokesperson Chrissy Webb with Montana Fish Wildlife and Parks says PAHs are found in various materials: “Some of them do exist in the environment naturally, specifically in certain rock formations, including some formations that are found within the Yellowstone River Basin. They are found in crude oil products, tar [and] come from car exhaust.”
State agencies took the most recent samples following the discovery of a mountain whitefish with high levels of a PAH in the follow-up to a Montana Rail Link derailment that spilled thousands of pounds of oil-based asphalt material into the river.
Agencies say the source of the PAHs remains unknown, and further testing is needed.
A consumption advisory is in place for all game and nongame fish from Indian Fort Fishing Access Site near Reed Point in Stillwater County to the Highway 212 bridge in Laurel in Yellowstone County.