Oranges are one of the most popular fruits in the U.S., but be aware that soon you may be sinking your teeth into an orange doused in antibiotics such as streptomycin and oxytetracycline, medications that are medically important to humans.
In December 2018, the U.S. Environmental Protection Agency (EPA) approved the “maximum level” of oxytetracycline for use in citrus fruits1 — just days after approving residues of the drug on fruit.2
The drug acts as a pesticide and is intended to suppress citrus greening disease, a devastating plant condition that’s been damaging citrus crops in Florida and other states. It’s unclear how much of the drugs will migrate to the orange flesh, and what the implications will be for the person who eats them, but on a larger scale it’s clear that spraying antibiotics freely into the environment on this scale is a recipe for disaster.
What Is Citrus Greening?
Citrus greening, also known as huanglongbing (HLB) or yellow dragon disease, is one of the “most serious citrus plant diseases in the world,” according to the U.S. Department of Agriculture (USDA).3 It’s spread by the Asian citrus psyllid, which feed on the trees and can infect them with the bacterium Candidatus Liberibacter asiaticus, which causes the disease.
Trees affected by citrus greening lose the ability to take in nutrients, causing problems with growth, resulting in smaller fruit, sour fruit and fewer fruits. Oranges, for instance, may remain green even when they’re ripe, and the fruit may be misshapen, bitter and hard. Leaves may become mottled and trees sparsely foliated.
Once infected, there’s no cure for citrus greening and most trees die within a few years. In the U.S., citrus production during the 2017 to 2018 season was expected to fall 24 percent to 3.5 million tons due in part to unfavorable weather, but also because citrus greening disease caused fruit in Florida to drop before it was ripe.4
Citrus growers are understandably desperately searching for a solution, which landed the trees on antibiotics. In 2015, Florida’s Department of Agriculture and Consumer Services asked the EPA for permission to spray 2.23 million pounds of antibiotics on orange groves to protect against the disease.5 Further, as reported by the Center for Biological Diversity:6
“In 2016 the EPA approved an emergency use of up to 1.6 million pounds of oxytetracycline and streptomycin, another medically important antibiotic, on citrus trees in Florida. This was followed by another emergency approval in 2017 for Florida, and for Florida and California in 2018.”
Antibiotics provide only a temporary band-aid, however, and won’t cure the disease. Instead, the antibiotics merely keep the trees alive and producing fruit a little bit longer, provided they’re repeatedly sprayed. Ultimately, even the antibiotic-treated trees will succumb to citrus greening.
“We’re using more of these antibiotics on fruit trees than to treat disease in humans,” Nathan Donley, a senior scientist at the Center, said in a news release. “Citrus greening disease is a serious issue, but using important antibiotics with limited effectiveness against the disease isn’t the solution.”7
Streptomycin Use May Also Be Expanded on Citrus Groves
The EPA proposed to expand the use of another antibiotic, streptomycin, to treat citrus greening disease and citrus canker, a bacterial disease that causes lesions on the fruit, leaves and stems along with premature leaf and fruit drop.
If approved, the proposal could mean more than 650,000 pounds of streptomycin could be applied to up to 480,000 acres of citrus trees in Florida each year, along with another 23,000 acres of citrus trees in California.8
The use of both oxytetracycline and streptomycin as pesticides on agricultural plants is banned in the European Union and Brazil, amid rising concerns over antibiotic resistance.
“This short-term agricultural fix is a horrible precedent that ignores the dangerous, long-term implications of overusing these medically important antibiotics,” Donley said. “The more we use these medicines in agriculture, the more likely they’ll lose their effectiveness when people fall desperately ill.”9
Oxytetracycline, for instance, is commonly used to treat respiratory tract infections such as pneumonia, along with some sexually transmitted infections. Streptomycin is typically used for serious bacterial infections for which other medicines may not work, such as tuberculosis.
“The … EPA is once again bowing to the pesticide industry’s wishes, with no regard for the consequences to human health, wildlife or the environment,” Donley said.10
Spraying Citrus Groves With Pesticides Could Accelerate Antibiotic Resistance, Harm Wildlife
Antibiotics have been sprayed on fruit orchards for years (streptomycin is registered for use on peaches, pears and apples, for instance), but at levels far lower than those currently approved.11
The nonprofit group Keep Antibiotics Working estimated that the state of Florida could end up using 36 times more streptomycin and four times more oxytetracycline on citrus trees than are used in Americans in a year. Steve Roach, food safety program director for the Food Animal Concerns Trust, told National Geographic:12
“Obviously this is a big problem for the citrus industry. But we are really concerned that they are asking to adopt routine antibiotic use, where they will pretty much have to be regularly spraying the whole industry. These are exactly the conditions we have been fighting against in animal agriculture: industrywide use of antibiotics on a regular basis.”
The antibiotics will also collect in soil and run off into surrounding waterways, and both the EPA and the U.S. Centers for Disease Control and Prevention have expressed concerns about the potential risks, the Center for Biological Diversity reported, adding:13
“In addition to increasing the risk of antibiotic-resistance, the EPA’s own analysis also indicated that the widespread use of streptomycin could have negative long-term effects on all mammals that forage in treated fields, including chipmunks and rabbits.”
Antibiotic Resistant Disease Is a Major Public Health Threat
In the U.S., according to CDC data, every year at least 2 million Americans acquire drug-resistant infections and 23,000 die as a result. Many others die from conditions that were complicated by antibiotic-resistant infections.14 Worldwide, 700,000 people die every year due to antibiotic-resistant disease, and it’s estimated that more people will be affected by it than cancer by 2050.15
Agriculture remains a driving force behind the surge in antibiotic-resistant disease, although typically this is talked about in regard to livestock living on concentrated animal feeding operations, rather than citrus groves.
In the former case, in November 2017 the World Health Organization (WHO) called on farmers and the food industry to stop the use of antibiotics for growth promotion and disease prevention in healthy animals. WHO explained, “The new … recommendations aim to help preserve the effectiveness of antibiotics that are important for human medicine by reducing their unnecessary use in animals.”16
They cited a 2017 study published in The Lancet Planetary Health, which found reducing antibiotic use in food-producing animals reduced antibiotic-resistant bacteria in the animals by up to 39 percent and may similarly reduce such bacteria in humans, particularly those who are directly exposed to food-producing animals.17
As it stands, the excessive use of antibiotics among CAFO animals has turned them into veritable “disease factories”18 and, in the U.S., when the FDA tests raw supermarket chicken, they routinely find antibiotic-resistant bacteria to be present.19
According to WHO, use of all classes of medically important antibiotics should be reduced in food-producing animals, while their use for growth promotion and disease prevention without diagnosed illness should be completely restricted. Allowing their use for widespread spraying on citrus trees, then, appears to contradict WHO’s goals in combating the spread of antibiotic resistant disease.
What’s at Stake if Antibiotic Resistance Spreads?
Already, tens of thousands of Americans may be vulnerable to life-threatening infections following surgery or chemotherapy due to antibiotic resistance. One study estimated that up to 50 percent of pathogens that cause surgical site infections, and 25 percent of those that cause infections following chemotherapy, are already resistant to common antibiotics.20
A 30 percent drop in effectiveness could mean another 120,000 infections and 6,300 deaths annually, the researchers concluded.21 Worse still, if antibiotic effectiveness declines by 70 percent, the U.S. could see 280,000 more infections and 15,000 more deaths as a result.
When spraying citrus with antibiotics, there’s also a risk that citrus greening disease could become resistant as well. To combat this, the industry has suggested cycling between oxytetracycline and streptomycin, but in a letter to the EPA, Keep Antibiotics Working suggests it’s not nearly this simple:22
“Florida makes the unsubstantiated claim that cycling between the two antibiotics streptomycin and oxytetracycline will ‘minimize any selection pressure’ and therefore can be considered ‘an effective resistance management program’ that will not only reduce resistance in the target organism but ‘should also help in preventing development of resistance in nontarget bacteria as well.’
The use of cycling of antibiotics as proposed here for the management of resistance is highly controversial even in human medicine and there is no clear evidence that it can be considered ‘an effective resistance management program.’”
What’s more, research from University of Canterbury researchers revealed that agrichemicals and antibiotics in combination increase the evolution of antibiotic resistance. In fact, bacteria may develop antibiotic resistance up to 100,000 times faster when they’re exposed to certain herbicides in the environment.23
The results suggest that herbicides enhance the ability of antibiotics to become antibiotic resistance and that such resistance may be acquired at rates much faster than those predicted in laboratory conditions. Previously, research found that commonly used herbicides promote antibiotic resistance by priming pathogens to more readily become resistant to antibiotics.24
Using antibiotics in another agricultural setting, where other agricultural chemicals are also being used, therefore has the potential to make antibiotic resistance exponentially worse — not to mention being harmful to wildlife and pollinating insects.
A Good Reason to Choose Organic Oranges
Typically, fruits with a thick peel, which you intend to remove before eating, are not the top priority for buying organic. However, it’s unknown whether agricultural antibiotics can be taken into the flesh of the fruit, so it’s better off to choose organic.
Even putting the health risks of consuming antibiotic residues aside, choosing organic means you’re not supporting the agricultural spraying of antibiotics that will only further the spread of antibiotic disease. It also means you’ll avoid exposure to citrus red No. 2, a toxic artificial dye that is sometimes sprayed on Florida oranges.
As Donley stated, the potential risks of this plan outweigh the benefits. “Our issue is that these drugs are a really lousy answer to a complex problem … This is just another example of the pesticide office of the EPA approving a pesticide that’s not been studied well enough for the agency to make a competent decision on its safety.”25