Don’t want antibiotics sprayed on your citrus? Sorry – it’s about to expand, big-time

By: - January 2, 2019 7:00 am

Julie Hauserman photo

The Trump administration has given the go-ahead for agricultural operations to spray antibiotics on nearly a half-million acres of Florida citrus, a move some scientists warn could increase the problem of antibiotic resistance in people and in the environment.

Federal officials are allowing greatly expanded use of streptomycin and oxytetracycline –  antibiotics often used on people — as a pesticide on commercially grown citrus. Agricultural operations plan to use the antibiotic sprays to combat the widespread disease called citrus greening, which has devastated the citrus industry. The antibiotics won’t cure the disease, and will have to be sprayed repeatedly over years just to keep the trees alive and producing fruit until they succumb to citrus greening.

Allowing so much antibiotic residue in Florida soils, runoff, and air is unprecedented. It’s unclear how much of the antibiotics – sprayed on leaves and taken up into the plant’s vascular system – will end up in fruit; it’s never been sprayed on this scale before. Test results the citrus industry provided to federal officials reported low antibiotic residues.

Scientists at the U.S. Environmental Protection Agency expressed concern, but ultimately ruled that the economic benefits outweigh the agency’s concerns about antibiotic resistance and potential harm to the environment, people, and wildlife. The amount of antibiotic exposure to people who eat fruit or juices is far less than what people are exposed to when prescribed antibiotics by their doctor, the U.S. Department of Agriculture reports.

The ramped-up antibiotic spraying was requested by Florida’s Department of Agriculture and by numerous citrus growers. Several public interest groups, including the Natural Resources Defense Council, the Center for Biological Diversity, the Johns Hopkins Center for a Livable Future, Food & Water Watch, and Keep Antibiotics Working are warning against it.

Antibiotic spraying has been used in apple and pear orchards for many years – including on an emergency basis for citrus recently in Florida –  but at much lower levels than what the Trump administration will now allow on Florida and California citrus. The Center for Biological Diversity says the new approval paves the way for up to 480,000 acres of Florida citrus to be treated with more than 650,000 pounds of streptomycin per year to combat citrus canker and citrus greening disease.

A chief concern is that the EPA hasn’t fully analyzed how spraying antibiotics at this scale could affect people, wildlife, and waterways, says Nathan Donley, the Center for Biological Diversity’s senior scientist. One EPA analysis notes that “uncertainty exists regarding the potential for development of resistance, or cross-resistance with other antibiotics, that could result from pesticide applications.”

Both the European Union and Brazil have banned the use of oxytetracycline and streptomycin for use as a pesticide on agricultural plants.

The World Health Organization and the U.S. Centers for Disease Control say antibiotic resistance is one of the world’s most pressing health problems, with the rise of factory farms using antibiotics to stop infection in meat and dairy animals. The concern is that the antibiotics which now work on human problems like pneumonia, tuberculosis and other deadly infections will become ineffective. Another concern is that the antibiotics will affect bees, which pollinate citrus flowers, as well as small mammals like rabbits. In the environment, antibiotics can change the chemistry of soil and water, knocking ecosystems out of balance.

“Researchers have been telling us for decades to curb the use of antibiotics in agriculture or risk losing them forever,” Donley said. “The Trump administration has chosen to ignore the science and blindly sprint down a path that could dead-end at bacterial resistance.”

For citrus growers, the last 10 years have been a nightmare as citrus greening spread from South Florida north, affecting groves in dozens of counties. They spray pesticides to kill the imported insect that carries the disease, but it hasn’t stopped citrus greening’s forward march up the peninsula. They are also working to develop new strains of citrus that resist the disease. The antibiotics, they argued in numerous comment letters to federal officials, are the only known way to stay in business. The press office of the Florida Department of Agriculture did not respond to requests for comment.

One strategy that agricultural officials and growers plan to try is to “cycle” between different antibiotics in hopes of thwarting antibiotic resistance which might develop in the citrus. But the group Keep Antibiotics Working says there’s not good science to show that would work.

“Florida makes the unsubstantiated claim that cycling between the two antibiotics streptomycin and oxytetracycline will ‘minimize any selection pressure’ and therefore can be considered a ‘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,’” Keep Antibiotics Working wrote in a letter to the EPA.

Donley of the Center for Biological Diversity and others say they sympathize with the struggling citrus industry, but believe this is the wrong solution and poses a massive risk.

“Our issue is that these drugs are a really lousy answer to a complex problem, and the potential for risk outweighs the benefits,” he said. “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. This happens a lot, where the pesticide office approves a pesticide without studies, then 10 to 15 years later we find out it has unintended consequences to human health or to environmental health and at that point it is often too late and the damage has been done.”


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Julie Hauserman
Julie Hauserman

Julie Hauserman has been writing about Florida for more than 30 years. She is a former Capitol bureau reporter for the St. Petersburg (Tampa Bay) Times, and reported for The Stuart News and the Tallahassee Democrat. She was a national commentator for National Public Radio’s Weekend Edition Sunday and The Splendid Table . She has won many awards, including two nominations for the Pulitzer Prize. Her work is featured in several Florida anthologies, including The Wild Heart of Florida , The Book of the Everglades , and Between Two Rivers . Her new book is Drawn to The Deep, a University Press of Florida biography of Florida cave diver and National Geographic explorer Wes Skiles.