Artificial Hormones

August 28, 2007

In 2005, 32.5 million cattle were slaughtered to provide beef for US consumers. Scientists believe about two-thirds of American cattle raised in for slaughter today are injected with hormones to make them grow faster and America’s dairy cows are given a genetically-engineered hormone called rBGH to increase milk production. These measures mean higher profits for the beef and dairy industries, but what does it mean for consumers? Although the USDA and FDA claim these hormones are safe, there is growing concern that hormone residues in meat and milk might be harmful to human health and the environment.

What’s in the Beef?
According to the European Union’s Scientific Committee on Veterinary Measures Relating to Public Health, the use of six natural and artificial growth hormones in beef production poses a potential risk to human health. These six hormones include three which are naturally occurring—Oestradiol, Progesterone and Testosterone—and three which are synthetic—Zeranol, Trenbolone, and Melengestrol.

The Committee also questioned whether hormone residues in the meat of “growth enhanced” animals and can disrupt human hormone balance, causing developmental problems, interfering with the reproductive system, and even leading to the development of breast, prostate or colon cancer.

Children, pregnant women and the unborn are thought to be most susceptible to these negative health effects. Hormone residues in beef have been implicated in the early onset of puberty in girls, which could put them at greater risk of developing breast and other forms of cancer. The European Union’s Committee reported that as of 1999, no comprehensive studies had been conducted to determine whether hormone residues in meat can be cancer-causing.

Scientists are also concerned about the environmental impacts of hormone residues in cow manure. Growth promoting hormones not only remain in the meat we consume, but they also pass through the cattle and are excreted in their manure. When manure from factory farms enters the surrounding environment, these hormones can contaminate surface and groundwater. Aquatic ecosystems are particularly vulnerable to hormone residues. Recent studies have demonstrated that exposure to hormones has a substantial effect on the gender and reproductive capacity of fish, throwing off the natural cycle.

Despite international scientific concern, the United States and Canadavii continue to allow growth promoting hormones in cattle. The European Union, however, does not allow the use of hormones in cattle production, has prohibited the import of hormone-treated beef since 1988, and has banned all beef imports from the US. The ban has been challenged by the US at the World Trade Organization and debate still rages between the US and the EU over its validity.

How Wholesome Is Your Milk?
Industrial farms use a number of methods for increasing milk production in dairy cows, including selective breeding, feeding grain-based diets (instead of grass), and exposing cows to longer periods of artificial light. Yet, one of the most common and controversial ways to force greater milk production is to inject them with rBGH (recombinant bovine growth hormone), a genetically engineered artificial growth hormone. Developed and manufactured under the brand names Posalic® by Monsanto Corporation, rBGH has been controversial from the start. (rBGH is also referred to as rBST, or recombinant Bovine Somatotropin.)

FDA approval for rBGH came in 1993, in spite of strong opposition from scientists, farmers and consumers. According to detractors, rBGH was never properly tested. The FDA relied solely on a study done by Monsanto in which rBGH was tested for 90 days on 30 rats. The study was never published, and the FDA stated the results showed no significant problems. But a review by the Canadian health agency on rBGH found the 90 day study showed a significant number of issues which should have triggered a full review by the FDA.

Read more about the FDA’s shady approval of rBGH…

By the summer of 1994, the Wisconsin Farmers Union and the National Farmers Union set up a joint hotline for dairy farmers to use when reporting problems with the artificial growth hormones in cattle. One lifelong New York dairy farmer reported losing a quarter of his herd to severe mastitis after beginning rBGH injections. He also reported a drastic drop in production after taking his cows off rBGH; they suddenly produced less milk then they had before going on the drug. A year later, he had to replace 135 of his original 200 cows. Other farmers using rBGH have reported similar problems, in addition to hoof diseases, open sores and cows that died from internal bleeding.

A 1991 report by Rural Vermont revealed serious health problems with the rBGH-injected cows that were part of a Monsanto-financed study at the University of Vermont (UVM). Among the problems was an alarming rise in the number of deformed calves and dramatic increases in mastitis, a painful bacterial infection of the udder which causes inflammation and swelling.xii To treat mastitis outbreaks, the dairy industry has relied on antibiotics. Critics of rBGH point to the subsequent increase in antibiotic use (which contributes to the growing problem of antibiotic resistant bacteria) and inadequacies in the federal government’s testing program for antibiotic residues in milkxiii as further reasons why the hormone should never have been approved.

Additionally, cows forced to produce unnaturally high quantities of milk will often become malnourished because they lose more nutrients through their milk than they ingest in their feed, xiv and are therefore more susceptible to disease.

Scientists have linked the rise in twin births over the last 30 years to bovine growth hormone in the food supply.
Milk from rBGH-treated cows contains higher levels of IGF-1 (Insulin Growth Factor-1), which has been linked to colon and breast cancer. Even though no direct connection has been made between elevated IGF-1 levels in milk and cancer in humans, scientists have expressed concern.

Faced with mounting evidence to the contrary, the FDA has stubbornly continued to assure consumers that rBGH is safe for cows and humans. In fact, in 1994, the FDA prohibited dairies from claiming there was any difference between milk from rBGH-injected cows and milk produced without the artificial hormone.

What You Can Do
There are many small family farmers who don’t use artificial hormones on their animals. By purchasing your milk and meat from local, sustainable farms, you are supporting a system that ensures the health and welfare of the farm animals, and protects you and your family from hormone-related health risks.

Choose hormone-free beef and rBGH-free dairy products at the supermarket. Foods that carry the “USDA-certified organic” label cannot contain any artificial hormones. When purchasing sustainably raised foods without the “organic” label, be sure to check with the farmer to ensure no additional hormones have been administered.

Visit the Eat Well Guide for an online listing of stores, restaurants and producers that sell hormone-free meat and dairy products.
Use Sustainable Table and Food and Water Watch’s rBGH-free dairy list to find a list of rBGH-free brands available in your state.

Did You Know?

-According to Science News, 80 percent of all U.S. feedlot cattle are injected with hormones.
-A study of cows treated with melengestrol acetate (one of the artificial growth hormones approved for use in the U.S.) revealed that residues of this hormone were traceable in soil up to 195 days after being administered to the animals.
-While the average dairy cow produced almost 5,300 pounds of milk a year in 1950, today, a typical cow produces more than 18,000 pounds.

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