The Hartford, Wis., resident says he has started a grass roots campaign to eliminate milk produced with the hormone from being served at West Bend High School, where he teaches science.
"I feel people who are expressing human health concerns [about the synthetic hormone] should not be seen as hysterical over this issue," Mr. Kellner said.
At least 20 other school districts in Wisconsin have expressed similar concerns, he added.
Mr. Kellner's approach to the controversy is typical of reaction in Wisconsin, where dairy product safety and sales are more of an issue than in the rest of the U.S.
Since the U.S. government approved use of the synthetic hormone in February, farmers in Wisconsin and around the country have started to organize a boycott against the maker, Monsanto Co. Local dairies are labeling products from untreated cows, and local retailers are posting signs that alert consumers about products with no added hormones.
Called bovine somatotropin or recombinant bovine growth hormone, the synthetic hormone stimulates increased milk production in cows. When the U.S. Food & Drug Administration OK'd use of rBGH, it said the hormone poses no health risk. The government doesn't require special labeling on rBGH treated products, saying the hormone naturally occurs in all milk.
On Feb. 18, Monsanto filed a lawsuit in U.S. District Court in Chicago against Swiss Valley Farms in Davenport, Iowa, after the milk processor notified retailers it wouldn't accept milk from treated cows.
Wisconsin dairy farmers responded by trying to organize a boycott.
"We're not questioning the safety of this product; what we're saying is many consumers are questioning the safety of the product," said Mark Kastel, director of government affairs for the Wisconsin Farmers Union.
In March, 253,000 members of the National Farmers Union passed a Wisconsin-sponsored resolution calling for the nationwide boycott.
The national Dairy Coalition said its research shows that though consumers are aware of the controversy, they haven't stopped buying milk. According to the Gallup Organization, 85% of Americans polled in February said their awareness of the issue had no effect on their milk consumption.
Still, Ben & Jerry's Homemade has added rBGH-free labels to its frozen desserts. And some supermarket chains, including Pathmark and Giant Food, have asked milk suppliers for products from untreated cows.
But in the Dairy State, passions run particularly high.
According to a February poll conducted by Wisconsin Public Radio and St. Norbert's College, 70% of Wisconsinites said they would be less likely to buy a dairy product if they knew it contained rBGH. Last December, Cedar Grove Cheese in Plain, Wis., began to label products as rBGH-free, but the state Department of Agriculture told it to stop selling items carrying those notices.
Bob Wills, owner of Cedar Grove Cheese, agreed not to sell the cheese again until early February, when clarifying label information was added about the FDA approval of products using milk from rBGH treated cows.
Since then, Mr. Wills said, sales "are out of control," growing 20% in six weeks.
Last month, the Wisconsin Legislature approved a bill that allows the use of an rBGH-free label if the product comes with affidavits stating milk producers didn't use the synthetic hormone.
Several other states have bills pending to govern the labeling issue as well as procedures to validate producers' rBGH-free claims.
Kwik Trip of LaCrosse operates a dairy to supply its 240 convenience stores, 166 of which are in Wisconsin. Signs at the outlets alert customers that the chain's dairy products come from untreated cows. The notices also carry an FDA statement that there's no known difference between cows that are treated with the hormone and those that aren't.
On March 1, Schultz Sav-O Stores, Sheboygan, asked its dairy supplier to provide milk from non-treated cows to the 95 Piggly Wiggly grocery stores the marketer operates in Wisconsin and Illinois. The company immediately posted signs in dairy cases alerting customers.
"We've had very positive customer comments from both the reaction in our supermarkets to calls to me personally," said Michael Houser, director of marketing for Piggly Wiggly.
Julie Liesse contributed to this story.