The Montana Department of Environmental Quality has reported that none of the 18 pharmaceutical chemicals that spilled into tributaries of the Gallatin River on March 3 pose any threat to human health.  About 35 million gallons of effluent drained from the Big Sky-area storage pond over the course of four days. The drugs detected ranged from antidepressants and acetaminophen to anti-fungicides and antibiotics.

Although Montana has no pharmaceutical water quality standards, it used criteria from Minnesota to see if any of the drug levels exceeded human health standards.  An earlier report issued by DEQ had noted the spill created an acute exceedance of Montana’s ammonia standards on Second Yellow Mule Creek on March 5.  Of greater concern to DEQ now is the large amount of dirt dumped into Second Yellow Mule Creek and that eventually ended up in the main Gallatin River.