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McDonald’s just ordered its meat suppliers to phase out antibiotics for promoting animal growth. It’s the second time in the past year that McDonald’s (search) has fed the public McNothing-burgers smothered in the pseudo-sauce of activist-defined corporate social responsibility.

Anti-meat and environmental activist groups, including the Center for Science in the Public Interest (search), Environmental Defense (search) and Union of Concerned Scientists (search), have been trying to scare the public for years about farm animal antibiotics use (search).

The activists claim 70 percent of antibiotics used in the U.S. are added to animal feed to promote animal growth and development. They allege such use of antibiotics causes bacteria to become resistant to antibiotics, making it more difficult to treat infections in humans.

The activists succeeded in convincing the Clinton-era Food and Drug Administration (search) to propose a ban on two antibiotics used in poultry.

The FDA claimed the drugs, known as fluoroquinolones (search), were a “significant cause” of an increased frequency of infections in humans by antibiotic-resistant Campylobacter bacteria (search), a pathogen contracted primarily from eating chicken.

Now the activists are patting themselves on the back for McDonald’s self-serving announcement.

“UCS and its members have pressured McDonald's to reduce antibiotic overuse for more than a year. Today, we are able to cheer McDonald's for rising to the challenge posed by many Americans on this crucial public health issue,” said a Union of Concerned Scientists spokesperson.

Following last August’s feel-good (but scientifically dubious) cooking oil switch to reduce consumer consumption of trans fatty acids, McDonald’s is once again hoping to score public relations points for action supposedly in the public interest.

It’s not clear, though, that farm animal use of antibiotics is a public health problem.

First, the activist estimate that 70 percent of all antibiotics are fed to animals is flat-out wrong. A more correct estimate is 10-15 percent.

The activists erroneously include discontinued drugs and drugs that, although approved by the FDA based on growth promotion claims, are actually used for disease prevention. Apparently it’s easier for pharmaceutical companies to obtain FDA approval for antibiotics based on general growth promotion claims rather than specific disease prevention and control claims.

Next, the claim of increasing human illness caused by antibiotic-resistant bacteria is questionable.

In the case of the FDA-proposed fluoroquinolone ban, for example, lawyers from drug manufacturer Bayer forced an FDA official to admit in an administrative hearing that the level of fluoroquinolone-resistant Campylobacter infections dropped by about 20 percent from 1997 to 2001 and is no longer the “most common known cause of foodborne illness.”

Most importantly, though, there is much scientific dispute about the nature and extent of antibiotic resistance (search) due to farm animal use of antibiotics.

“This issue has been the subject of heated debates for many years, however, there is still no complete consensus on the significance of antimicrobial use in animals on the development and dissemination of antibiotic resistance among human bacterial pathogens,” wrote FDA scientists in the May 2002 issue of the journal Animal Biotechnology.

“Although research has linked the use of antibiotics in agriculture to the emergence of antibiotic-resistant foodborne pathogens, debate still continues whether this role is significant enough to merit further regulation or restriction,” added the FDA scientists.

But it’s also worthwhile questioning the research that allegedly links farm animal use of antibiotics with human illness.

A May 1999 study, for example, reported a foodborne outbreak of salmonella poisoning that sickened 27 people and caused two deaths in Denmark. The bacteria were resistant to fluoroquinolones. Danish investigators traced the outbreak to a slaughterhouse, where a herd of swine was infected with the same antibiotic-resistant strain of bacteria.

Although the then-president of the American Society for Microbiology (search) described the study as “the closet that anyone has come to a smoking gun” linking farm use of antibiotics to antibiotic resistance, the study’s researchers confessed it impossible to determine how the swine became infected with resistant salmonella (search).

They didn’t know whether the bacteria were introduced by pigs outside of Denmark, wild animals or equipment. Fluoroquinolones weren’t used in those herds that year. Prior use of fluoroquinolones couldn’t be blamed either.

If that’s a “smoking gun,” somebody’s been smoking something.

It’s ironic that while scientists debate this complex issue, the corporate headquarters of Ronald McDonald and the Hamburglar thinks it already knows the answer.

McDonald’s, of course, is simply trying to score public relations points by appearing to be “socially responsible” amid meritless litigation alleging harmful health effects caused by its fatty, salty and sugary fast food fare.

Given the new reality of frivolous lawsuits, it certainly seems an inauspicious time for McDonald’s to embrace junk science.

Steven Milloy is the publisher of JunkScience.com, an adjunct scholar at the Cato Institute and the author of Junk Science Judo: Self-defense Against Health Scares and Scams (Cato Institute, 2001).

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