Should Citrus Farmers Use Antibiotics to Combat Greening Disease?

When you hear about antibiotic use in agriculture, it is almost always about the kind of routine everyday use in livestock that the Food and Drug Administration is trying to eliminate. But there’s another type of antibiotic use in agriculture. It may be less known, but it’s poised to generate just as much controversy: spraying the drugs on citrus trees.

Florida’s Department of Agriculture and Consumer Services has applied to the U.S. Environmental Protection Agency for permission to spray 2.23 million pounds of antibiotics on its orange groves as a protection against a devastating disease. But the drugs the state is asking to use are also important human antibiotics, so campaigners concerned about the spread of antibiotic resistance are asking the EPA to block the proposal. Florida believes that its citrus industry is at stake, so the stage is set for a fight.

The looming fight over produce antibiotics is pretty different from the long-standing fight over livestock antibiotics. In meat animals, the drugs were first used to make animals put on weight faster, and subsequently to prevent diseases that spread in crowded barns and feedlots. According to the FDA , livestock gets about 33.86 million pounds of antibiotics per year.

A citrus tree is tented and the sun bakes it to kill bacteria that cause citrus greening. Photograph by Craig Cutler

A citrus tree is tented and the sun bakes it to kill bacteria that cause citrus greening. Photograph by Craig Cutler, NG Creative

In Florida, if approved, the drugs will be used to treat an existing disease, a bacterial infection called huanglongbing, also known as “citrus greening.” (Citrus greening is spread by a tiny insect called the Asian citrus psyllid.) But it won’t, strictly speaking, cure the infection, though it will help the trees to survive longer.

In one way, though, livestock use and citrus use would be similar: They would both use many times more antibiotics than are used in human medicine. One set of comments to the EPA, made by the nonprofit coalition Keep Antibiotics Working, estimates the state is asking to use four times as much oxytetracycline and 36 times as much streptomycin as are used in U.S. patients each year. Advocates worry that such high doses may increase the risk that the drugs will stop working in humans—the fear that lies behind objections to livestock antibiotics.

“Obviously this is a big problem for the citrus industry,” says Steve Roach, who is food safety program director for the Food Animal Concerns Trust, a Chicago-based nonprofit that belongs to the coalition. “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: industry-wide use of antibiotics on a regular basis.”

In its 59-page request—technically, a petition for an emergency exemption from Section 18 of a law called the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA)—the Florida department says that other attempts to combat the disease since it arrived in the state a decade ago have failed.

“Between 2004 and 2014, the amount of Florida land planted with citrus shrunk by nearly one-third, from 748,555 acres down to 515,147 acres,” Adam Putnam, the Florida Commissioner of Agriculture, says in the petition. “During that same timeframe, overall citrus production in the state dropped from 292 million boxes of fruit down to 124 million boxes (a 58 percent reduction). Average orange yields sunk from 428 boxes per acre in 2004 down to 250 boxes an acre in 2014 (a 42 percent reduction), despite the higher-density new plantings of orange trees, almost solely resulting from HLB infection.”

The petition was filed December 4, 2015, and seems to have slipped through without much notice. The public comment period closed earlier this month, and at least 50 of the 56 comments are supportive ones from citrus growers and industry figures:

W.R. Holmes, described in the EPA docket as a “small citrus grower in Seminole County, Florida”: “Our Hamlin orange production was down 50 percent this year’s harvest following a 15 percent reduction in all oranges last year.”

Michael Carter, a citrus grower from Desoto County, Florida: “This is a Hail Mary as far as my business is concerned.”

Douglas C. Bournique, executive vice president of the Indian River Citrus League: “(Citrus greening) has reduced our fresh fruit packinghouses from 40 to 10, and our grower membership has dropped from 1,200 to 300.. Florida citrus growers need effective tools now for our industry is on life support.”

Joel Nelson, president of the trade association California Citrus Mutual (California has not experienced citrus greening—yet): “The situation in Florida is past the emergency status, it is a crisis. It is a crisis in the Western Hemisphere and citrus producing areas around the world. According to the Brazilian government, over 26 million infected trees have been removed from citrus production in the country. States in Mexico all have HLB and the quality of their product let alone quantity has been adversely affected. Texas now reports the disease in commercial areas and China has announced that notwithstanding the wholesale movement of their industry from one geographical area to another, HLB is back and already affecting production.” (For more on the spread of the disease, see On Beyond Orange: Seeking Out New Citrus Varieties.)

But the few advocates who oppose the plan say the lavish use of antibiotics could harm pollinators that are also crucial for citrus tree survival, as well as creating antibiotic-resistant bacteria that could harm humans—and, possibly, create a resistant version of citrus greening itself.

“We… share the concern that the application of these antibiotics in very large quantities may become routine,” Avinash Kar and Carmen Cordova, an attorney and scientist for the Natural Resources Defense Council, wrote the EPA. “This would undermine various efforts under way both in human medicine and animal agriculture, including federal efforts, to reduce antibiotic use and thus the spread of resistance, and would add a significant new risk for the spread of resistance.”

It isn’t clear when the EPA will rule.

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