Wildlife officials have been pushing the idea for years, but many anglers have stuck with their traditional lead tackle.
MPCA spokeswoman Rebecca Helgesen said many people probably don't realize how poisonous lead can be -- for instance for eagles, eating lead-contaminated fish, and for loons, picking up small stones from the lake bottom to help digestion.
"All it takes is for a loon to eat one lead sinker, get sick and die," Helgesen said.
Helgesen said in some areas in the upper Midwest, as many as half of loons are killed by lead poisoning.
Some states have banned lead sinkers, but they're still legal in Minnesota. Alternatives to lead include tackle made of steel, tin and bismuth.