Minnesota officials have tested 1,239 samples of venison donated to food shelves last fall and found that 273, or 22 percent, had evidence of lead bullet fragments.

That percentage is similar what was announced in April after about 300 samples had been examined with X-ray equipment.

But the extent of the issue continues to surprise and perplex officials.

Because all of the donated venison was processed commercially, some have suggested that careless processors might be at least partially to blame.

But the Minnesota Department of Natural Resources collected and tested 123 samples from DNR employees who processed their own deer themselves. They found about 18 percent had some lead contamination.

"I was shocked," said Lou Cornicelli, DNR big-game program manager and a deer hunter whose own venison had some lead contamination. "I'm pretty careful how I trim around wound channels."

The latest information came as 40 wildlife, health and agriculture officials from seven Midwest states gathered Wednesday in Bloomington to discuss how to respond to what has become a major wildlife and health issue.

"This isn't a state issue, it's a national issue," DNR Commissioner Mark Holsten said. "It's not going away."

Officials hope the Midwest states can provide similar messages to hunters regarding lead and venison to avoid confusion. "We need to all be on the same page," Holsten said.

Officials are trying to develop guidelines for hunters and deer processors before fall that might reduce the amount of lead fragments in venison.

Representatives came from Minnesota, Wisconsin, Iowa, North Dakota, South Dakota, Michigan and Missouri. Four of the states have found lead in donated venison.

Because of the discovery, the future of venison-donation programs in Minnesota and several other states is uncertain.

Natural resource agencies desperately want to retain the venison-donation programs because they encourage hunters to reduce overpopulations of deer while providing food shelves with high-protein meat to distribute.

"It's a very important deer management tool," said Dennis Simon, DNR wildlife management section chief.

Minnesota's deer hunters and food shelf consumers should know by the end of the month whether the state venison-donation program, which was launched just last fall, will continue.

Officials also discussed issuing venison consumption guidelines for food shelf users. Because even low lead levels can be harmful to young children and pregnant women, they could recommend that they not consume donated venison.

Few studies have been done on the extent of lead contamination in venison and the possible effect on consumers.

Venison samples still are being examined in Wisconsin and Minnesota.

In North Dakota, the Centers for Disease Control and Prevention is testing lead levels in the blood of 738 residents, including venison eaters.

"I think the whole nation is waiting to see the results," said Sandi Washek of the North Dakota Department of Health.

dsmith@startribune.com • 612-673-7667