Reduced Fitness of Daphnia magna Fed a Bt-Transgenic Maize Variety

By Thomas Bøhn (1) , Raul Primicerio (2), Dag O. Hessen (3) and Terje Traavik(1,4)
Archives of Environmental Contamination and Toxicology
Received: 16 November 2007 Accepted: 11 February 2008 Published online: March 18, 2008

Abstract

Genetically modified (GM) maize expressing the Bt-toxin Cry1Ab (Bt-maize) was tested for effects on survival, growth, and reproduction of the water flea Daphnia magna, a crustacean arthropod commonly used as a model organism in ecotoxicological studies. In three repeated experiments, D. magna were fed 100% ground maize in suspension, using either GM or isogenic unmodified (UM) maize. D. magna fed GM-maize showed a significantly reduced fitness performance: The mortality was higher, a lower proportion of females reached sexual maturation, and the overall egg production was lower compared to D. magna fed UM isogenic maize. We conclude that the tested variety of Bt-maize and its UM counterpart do not have the same quality as food sources for this widely used model organism. The combination of a reduced fitness performance combined with earlier onset of reproduction of D. magna fed Bt-maize indicates a toxic effect rather than a lower nutritional value of the GM maize.

Mexico Approves Rules to Begin Planting GM Corn

By Mica Rosenberg
Reuters
March 20, 2008

MEXICO CITY - Mexico, widely thought to be the birthplace of corn, said on Wednesday it will begin allowing experimental planting of genetically modified crops, despite resistance from some farmers who question their safety.

The regulations published in the official gazette are the last step needed to implement a law passed by Mexico's Congress in December 2004 that authorizes controlled GMO plantings.

Supporters of GMO foods, whose DNA is altered to be resistant to pests, say they are a way to boost world food supplies. But farmers in Mexico's rural south, where corn has been grown for thousands of years, worry GM corn will cross-pollinate with native species and alter their genetic content.

Under the new rules, the farmers who want to plant GMO crops must register with the agriculture ministry and environmental authorities to request a permit.

GMO corn seeds will not be allowed into certain parts of the country that are determined to be "centers of origin" for genetically unique corn strains found only in Mexico.

Bio-tech food producer Monsanto Co welcomed the decision in a statement, although the company noted that "the passage of these rules does not mean that permission will automatically be granted" to plant GMO crops.

Some farmers decried the decision.

"This is a step in the government's intention to bow to pressure from Monsanto to allow the contamination of Mexico's native corn," said Victor Suarez, who leads a group of small farmers opposing GMO crops.

Corn was first planted in Mexico as some 9,000 years ago and the country is now home to more than 10,000 varieties. The grain was adopted by Spanish conquistadors in the early 1500s and eventually spread to the rest of the world.

On Jan 1 Mexico, the United States and Canada lifted all corn tariffs under the 1994 North American Free Trade Agreement. Mexico now imports between 8 million and 9 million tonnes of U.S. yellow corn a year, close to 35 percent of local consumption.

More than 70 percent of U.S. corn is genetically modified.

With U.S. corn prices hitting record highs near $6 a bushel on increased demand for corn-based ethanol, corn farmers in the north say GMOs will help Mexicans cut down on expensive U.S. imports by producing more at home.

Wal-Mart Move 'Tipping Point' for Non-Hormone Milk

By Janet McFarland
The Globe and Mail
March 22, 2008

Organic food proponents will remember Thursday as the day the ground shifted.

Giant food retailer Wal-Mart Stores Inc. announced that its store brand milk in the United States will now come exclusively from cows not treated with artificial growth hormones.

The move sends a powerful signal to food manufacturers about the growing mainstream demand for health food products. With Wal-Mart already the largest retailer of organic milk in the U.S., it has been clear that consumers interested in greener food products are no longer the narrow group of back-to-the-earth types and wealthy urban yuppies.

"It's reached the tipping point," said Ronnie Cummins, director of the Organic Consumers Association in the U.S., who has spent years campaigning against the use of hormones designed to boost milk production by up to 15 per cent in dairy cows.

"Even Wal-Mart's customers are demanding milk free from genetically engineered hormones."

Similar demands are growing in Canada, with mainstream grocery retailers like Loblaw Cos. Ltd. introducing reams of new products to meet mainstream demands for organic and "green" foods. Canada, however, banned artificial growth hormones for dairy cows in 1998, so is not affected by the milk changes sweeping the United States.

"I think things are accelerating now and people are getting more health conscious and are getting more conscious about the connection between their personal health and the health of the environment," Mr. Cummins said.

Grocery chain Kroger Co., with 2,500 stores in the U.S., began last month selling only milk produced without the use of hormones like recombinant bovine somatotropin (rBST). Safeway Inc., with more than 1,700 stores, has switched its in-store brands to non-rBST milk, though it also sells other brands produced from cows given the hormone. And starting in January, Starbucks Corp. has only used non-rBST milk in its stores.

As the largest grocery retailer in the United States with more than 4,000 locations, however, Wal-Mart was the "big get" for consumer advocates.

The retailer said Thursday that its change was prompted by consumer demands. "Many Wal-Mart customers have expressed a desire for milk choices," the company's release said. The change means Wal-Mart's Great Value store brand milk will be rBST-free, as will milk offered at the company's Sam's Club warehouse locations.

"We've listened to customers and are pleased that our suppliers are helping us offer Great Value milk from cows that are not treated with rBST," said Wal-Mart general merchandise manager Pam Kohn.

In the U.S., non-rBST milk has become a cheaper alternative to milk that is fully organic. Mr. Cummins said it appeals to many consumers who want to avoid the hormones but are unwilling to pay the far larger premium for organic milk. "When you look at all the surveys of consumer attitudes about food safety, hormones consistently rank way up there, along with pesticides," he said.

Most dairy farmers do not use the artificial hormones, which were first approved by the U.S. Drug Administration in 1993, so the impact on the industry from Wal-Mart's announcement will be incremental rather than dramatic. Mr. Cummins said USDA statistics show 18 per cent of U.S. dairy cows were given artificial hormones in 2006.

David Darr, vice-president of public affairs for Dairy Farmers of America Inc., a major U.S. producer of milk and dairy products, said yesterday that there is already a lot of non-rBST milk available.

"There are more dairy farms across the U.S. that don't use it than do," he said. "And the farms that did use the technology, they did not necessarily use it on every cow."

His firm, a co-operative owned by 18,000 dairy farmers, has members who produce both kinds of milk.

"We continue to try to give our members a choice on what technology they use, and try to find markets for milk however they want to produce it," he said. "But we are also cognizant and recognize the needs of our customers and try to give them what they want."

Kroger in Milk Label Battle

By John Eckberg
The Enquirer
March 26, 2008

The Kroger Co. and chemical giant Monsanto are in a state-by-state spat over how milk should be labeled in stores.

Kroger wants to tell consumers in more than 3,200 groceries and convenience stores through a product label that the milk produced and sold by Kroger dairy plants is free of a hormone produced by Monsanto called Posilac or rBST.

The substance, injected into cows, can boost milk production by 10 pounds per day.

Monsanto opposes those labels and claims they are disparaging to a legal and appropriate additive. It has fought labeling plans in Pennsylvania, Ohio and Utah - with more states likely to become battlegrounds - and insists that if Kroger is permitted to put the information on a label, Monsanto will have no way to rebut implications that the bovine supplement is unsafe.

The Food and Drug Administration has approved its use in the United States, said Monsanto spokesperson Lori Hoag, who acknowledged that the product is not registered for use in Canada.

"There is no difference in the milk," said Hoag. "There is absolutely no difference in the milk."

The retail battle pits the rights of consumers to know what's in a product against a powerful player in the agriculture industry, Monsanto, which is based in St. Louis. The FDA approved used of the supplement in 1993.

The issue came to a head this month in Ohio. Why does Kroger need a label?

"No.1, rBST isn't there - isn't in the milk," said Meghan Glynn, Kroger spokeswoman. "And there's increasing customer interest in this issue. We are getting a lot of calls on this."

The fight has already forced Kroger to change plans for millions of proposed milk labels after Gov. Ted Strickland on Feb. 7 issued an emergency order to prevent the Cincinnati-based retailer from using the label.

Kroger notified dairies last summer that by February 2008, it would not sell milk from cows that had been given rBST.

The retailer had proposed a two-part label: one line in the notification said that the milk came from cows that were not treated with artificial bovine growth hormone and in smaller print was an explanation that the FDA had found that the hormone rBST - also known as rBGH - was safe.

The smaller print became an issue of contention as Ohio regulators told Kroger it could not proceed with the label and had to make changes.

Ohio is not the first state where this issue has played out.

Pennsylvania banned the labels, known in the food industry as "absence labels" on Jan.1, but that prohibition was later altered to allow milk to be labeled as from cows that were not treated with rBST.

Kroger has found a powerful ally in the International Dairy Food Association.

"Let's be clear about one thing: The reason why processors are marketing products with absence claims is simply because consumers are demanding it," dairy foods association executive Jerry Slominski said.

"If you don't believe me, just ask parents who buy milk for their children if they prefer milk from cows that have not been treated with artificial hormones."

In Ohio, where Kroger has 214 stores, the issue raises big questions for other national food producers that want to sell products in Ohio and label those dairy products as coming from cows not treated with the hormone, said Slominski.

"Ben and Jerry's is very concerned about rules like in Ohio," Slominski said. "It's part of their marketing strategy to produce ice cream that is not related to rBST. So companies have a seven-word claim and then an 18-word disclaimer behind it?

"That's putting more material to make Monsanto's case on the label. It's a problem."

Both sides wait as regulators consider the issue.

After Strickland ordered that the absence label must contain a statement of FDA safety, the Ohio Department of Agriculture agreed to permit the emergency ruling that prohibits Kroger labeling to stand. In the meantime, with Kroger milk currently unlabeled, the department has asked the state's Joint Committee on Agency Rule Review to endorse its decision.

That hearing is scheduled for March 31.

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