Here’s some unfortunate, but not so surprising news: The Food and Drug Administration has allowed 30 potentially harmful antibiotic additives to remain approved for use in food animals (cows, pigs and chickens), even though the agency’s own scientists found them to pose a risk to human health or lack necessary data on safety. Documents that NRDC acquired from FDA through a Freedom of Information Act lawsuit show FDA’s own scientific review stating that the use of these drugs in livestock has not been shown to be safe for human health. And FDA scientists classified 18 of the 30 drugs, in their current use, as presenting a “high risk” of adversely affecting public health.
NRDC compiled all of this data into a new report we released today called Playing Chicken with Antibiotics. As we outline in the report, FDA initiated an internal scientific review in 2001 on 30 penicillin and tetracycline feed and water additives for “subtherapeutic use” (non-treatment uses such as speeding up animal growth) in poultry and livestock production. Despite FDA scientists finding that at least 29 of the antibiotic additives are not proven to be safe, no action has been taken to withdraw approval. According to our research, twenty eight remain approved for use in livestock production and many remain on the market. Here’s a breakdown of the findings:
- None of the 30 antibiotic additives would likely be approved as new additives for livestock use if submitted under current FDA antimicrobial safety guidelines, because drug makers have not submitted sufficient information to establish their safety.
- 18 of the 30 antibiotic feed additives reviewed (nearly two out of three) were assessed as posing a “high risk” of adversely affecting human health. They could not be approved today for their current use.
- Drug manufacturers never submitted sufficient information for the remaining 12 products to establish safety, meaning there is no proof of their safety for humans when used in animal feed and the products could not be approved today.
- 29 of the reviewed additives fail to satisfy FDA’s first iteration of safety requirements from 1973
These findings are troubling for a number of reasons. The report again draws attention to continued FDA inaction on antibiotics used in poultry and livestock production amidst mounting evidence of a threat to public health. Medical and scientific authorities have consistently warned of the dangers of antibiotic resistance and pointed to animal use of antibiotics as a contributor to the problem. The Centers for Disease Control and Prevention has stated that studies “establish a clear link between antibiotic use in animals and antibiotic resistance in humans.” A study last year showed that living closer to swine facilities and fields treated with swine manure is associated with a greater likelihood of antibiotic-resistant skin infections, such as MRSA. In this context, FDA should be protecting our health and clearly, inaction in the face of “high risk” isn’t consistent with that role. A failure to provide sufficient evidence of safety in the context of these risks should certainly not be a free pass to continue use.
It’s worth noting that while this review covers only penicillin and tetracyclines, just two of the several classes of antibiotics used in animal feed, similar risks probably follow from the use of all other medically important antibiotics used in animal feed. For instance, we know that, in Guidance 213, FDA itself seeks to limit the use of all classes of antibiotics currently used for growth promotion. FDA itself clearly sees a public health threat in the use of any medically important antibiotic in animal feed, which makes its lack of action even more frustrating.
What this all points to is a very real health threat. Antibiotics are becoming less and less effective because we’re overusing and misusing them. It is leading to antibiotic-resistant bacteria that we can’t fend off as easily. Today, 70 percent of all medically relevant antibiotics sold in the United States are sold for use in livestock production—not on humans. And nearly half of those used in livestock are penicillins and tetracyclines. Unfortunately, both penicillins and tetracyclines are no longer effective for treating some infections because of high levels of resistance in bacteria, likely brought on, in part, due to their widespread use in industrial farms. Increasing resistance to these drugs decreases the options available for human treatment.
However, the threat from the use of these drugs in animal feed is not contained to these two classes of drugs alone. A large body of scientific work on bacterial cross- and co-resistance has established that bacterial resistance of one antibiotic can actually lead to resistance to other antibiotics. Consequently, the 30 penicillin- and tetracycline-based animal feed additives in this analysis could reduce the effectiveness of a range of other medically important antibiotics that are solely used to treat people.
This example makes clear that FDA should immediately move to address the concerns identified in their very own findings. Collectively, the report shows that FDA believes that the use of antibiotics in animal feed poses a risk to the health of people. We need FDA to heed its own warnings and limit the uses of medically relevant antibiotics in agriculture. We need to protect these miracle drugs for when we need them most – to cure sick people.