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In 1950, a group of scientists made a new discovery that would change the way we produced and sold meat in this country forever: subtherapeutic doses of antibiotics were found to not only keep animals safe from infectious diseases but also to increase their growth rate, thus facilitating the production of more meat in less time (and for less money).
Related: 3 Ways Antibiotics Can Do More Harm Than Good
“They are quite effective in terms of what we would technically refer to as feed conversion: the efficiency of taking feed and creating pounds of flesh and fat on an animal,” explains Mark Kastel, co-founder of the organic watchdog group the Cornucopia Institute.
This practice is now used extremely widely, to such an extent that 80% of all antibiotics distributed in the United States were sold for use in food-producing animals in 2011, according to the FDA. But this practice has a few major repercussions on the health and wellbeing of humans, animals, and the world at large.
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“The world is heading towards a post-antibiotic era in which common infections will once again kill,” Margaret Chan, MD, MSc, and two-term Director-General of the World Health Organization, said last April. “If current trends continue, sophisticated interventions, like organ transplantation, joint replacements, cancer chemotherapy, and care of pre-term infants, will become more difficult or even too dangerous to undertake. This may even bring the end of modern medicine as we know it.”
What’s The Problem With Antibiotics In Food?
When livestock are fed large amounts of antibiotics, whatever is not metabolized by animals is excreted and becomes part of the agricultural waste of the farm. According to a study in the Upsala Journal of Medical Sciences, antibiotic residues are regularly spread on farmland via the manure of treated animals, which could be detrimental for the microorganisms found in these soils.
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One of the most recent studies on this phenomenon, published in 2017 in Microchemical Journal, found that the potential for antibiotics to cause harm to the environment was alarming, even in small amounts.
"The amount of antibiotics is very, very low—there are normally nanograms per liter of these molecules found in natural environments," said Paola Grenni, PhD, a microbial ecologist at the National Research Council's Water Research Institute in Italy and one of the study’s co-authors. "But the antibiotics and also other pharmaceuticals can have an effect even in low concentrations."
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The study authors called the widespread use and presence of antibiotics in the environment a “real-life experiment” whose consequences are still not fully known or understood. "There are only a few researchers working in this field, but it's very important," Grenni said. "We need to know the different molecules we normally use that are in the environment and the effect they have. We need more research in this field."
The Contribution Of Subtherapeutic Antibiotics To Drug-Resistant Super-Bacteria
There is, however, one area where we are very aware of the repercussions of subtherapeutic antibiotics: the increased prevalence of drug-resistant super-bacteria. The Upsala study calls drug-resistant super-bacteria “the greatest concern about antibiotics in the environment."
In 2015, the situation became dire, when bacteria with the mcr-1 gene—a gene that creates resistance to last-resort antibiotics—were found first in hogs in China and, soon after, in the United States. Even colistin, which the Washington Post reports is used “against particularly dangerous types of superbugs that can already withstand many other antibiotics,” cannot treat these infections. While rarely used in humans, as it can cause serious kidney problems, colistin is commonly used in subtherapeutic doses in farm animals. At the end of May 2017, two of six pediatric leukemia patients in China found to have colistin-resistant bacterial infections died. (Here's why one person stopped eating factory-farmed pork.)
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The U.S. Centers for Disease Control and Prevention (CDC) estimates that 23,000 people die every year in the Untied States from antibiotic-resistant infections, a number that is expected to rise to 317,000 in North America and 10 million worldwide, according to a Review on Antimicrobial Resistance commissioned by the UK Prime Minister.
“Antibiotic resistance is perhaps the single most important infectious disease threat of our time,” says Beth Bell, the head of prevention and control of infectious diseases at the CDC.
Watch 13 really weird things that organic gardeners do:
How To Avoid Antibiotics In Food
The practice of using subtherapeutic doses of antibiotics was banned in Europe in 2006, and while certain “medically important” antibiotics are no longer allowed to be used for growth promotion in the United States as of January, by and large, these drugs are still omnipresent in meat and dairy produced by conventional ag.
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The rising awareness of the issue has led several restaurant chains in the United States, including KFC, Burger King, and Wendy’s, to commit to phasing out some or all of these subtherapeutic antibiotics. But it remains difficult to see exactly what’s allowed.
Some companies have committed to removing only “critically important antibiotics,” a category defined by the World Health Organization that includes drugs that are essential for human use, including penicillin, while others have committed to using the drugs only “when necessary,” a practice that Kastel is skeptical of.
“There's a bit of a grey area,” says Kastel. “They’ll say, ‘We'll only administer them when necessary' (wink wink nudge nudge), but the majority of conventional livestock are housed in what I would refer to as abhorrent conditions: very crowded, susceptible to disease and infection.” Necessity would then dictate a far more prevalent use of these antibiotics than most who are aware of this issue would be comfortable with.
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The answer, at least for now, is to opt for certified organic meat, dairy, and eggs, where the use of all antibiotics—whether for illness or for growth promotion—is prohibited.