BILLINGS — Detectable levels of petroleum were found in tests of fish pulled from the Yellowstone River downstream from a broken petroleum pipeline near Glendive last month. This week Montana Fish, Wildlife and Parks advised fishermen to use caution when deciding whether to eat fish caught in the area affected by the oil spill.
On Jan. 17, 2015, the Bridger pipeline broke where it crossed the Yellowstone River upstream from Glendive, dumping crude oil into the water. FWP advised anglers not to eat any fish caught downstream from the spill until biologists could test for petroleum in the edible muscle tissues.
Sampling for contaminated fish – as well as cleanup of the spilled oil – has been difficult because ice covers most of the river downstream from the spill site. FWP fisheries biologists were able to catch shovelnose sturgeon, sauger, channel catfish, goldeye, burbot and shorthead redhorse suckers at sites downstream from the break. The fish were sent to laboratories in Billings and Wisconsin, which tested the edible muscle tissue as well as various internal organs for polycyclic aromatic hydrocarbons – or PAHs.
Trevor Selch of Helena, FWP’s pollution control biologist, said this week that the laboratories have tested some of the tissues and returned results showing detectable levels of PAHs in some of the sauger, goldeye and shovelnose sturgeon muscle tissues. FWP is waiting for results from the other tests.
Published research indicates that petroleum compounds can accumulate in fish for 40 or more days after a spill. FWP will resume catching fish after the ice leaves the river and test tissues for PAH accumulation. Petroleum compounds can also be passed on to fish through the food chain when micro-organisms, insects, worms, crustaceans and other aquatic animals absorb petroleum compounds then are eaten by fish.
Until all of the tests are complete and the data is analyzed, Selch advised anglers to continue to use caution when deciding whether to eat fish.
The advisory was issued as a precaution, advising anglers to tend toward conservative decisions and prudent practice when it comes to the health effects of the oil spill.