Mercury levels are increasing in pike and walleye in Minnesota. Minnesota Pollution Control Agency scientist Bruce Monson studied data from the past 25 years.
Monson found that from the 1980s through the mid 1990s mercury levels decreased, but since then they've been on the rise. Monson says that corresponds to an increase in global mercury emissions from 1990 to 1995.
"We're affected by global emissions. 90 percent of the mercury that gets deposited is actually from outside the state."
Minnesota has already greatly reduced its mercury emission levels, and it will cut emissions again by 93 percent by 2025. The state is also working with other states to push the federal government into take action to cut mercury pollution globally.