Since its discovery in 1943, doctors have relied on the antibiotic streptomycin to treat tuberculosis and deadly bacterial infections around the globe.

Each year, Americans ingest about 14,000 pounds of aminoglycosides, the antibiotic class that includes streptomycin, to ward off potentially life-ending infections.

Now, a new rule from the U.S. Environmental Protection Agency raises alarm surrounding streptomycin and drug-resistant infections. The rule will allow citrus farmers to spray this medically necessary antibiotic on 764,000 acres of orange groves in Florida, California and other citrus-producing states.

This decision paves the way for the most extensive use of a medically necessary antibiotic in cash crops to date, as the New York Times reported.

Farmers will be allowed to spray more than 650,000 pounds of streptomycin — a 26-fold increase over the amount currently used to heal patients. Whether this level of antibiotic spraying is safe for humans and wildlife remains unclear, although consumer advocates argue the rule is ill-founded and dangerous.

Citrus growers claim the antibiotic is essential to combat a greening disease that is decimating orchards.

But the U.S. Centers for Disease Control and Prevention, World Health Organization, and United Nations voiced vehement objections to using streptomycin as a pest-killer.

Their chief complaint: spraying the antibiotic on crops would needlessly inflame the “unchecked escalation of antibiotic resistance,” which the WHO considers one of the top health concerns worldwide

Streptomycin

Emphasized by the WHO as vital to human medicine, streptomycin is a long-standing treatment for tuberculosis infections and rare, but deadly, outbreaks such as the bubonic plague.

FDA labeling cautions against overuse of the antibiotic, noting “to reduce the development of drug-resistant bacteria and maintain the effectiveness of streptomycin and other antibacterial drugs, streptomycin should be used only to treat or prevent infections that are proven or strongly suspected to be caused by bacteria.”

The rise of drug-resistant germs

Some scientists warn that the heavy use of human antibiotics in agriculture could trigger mutations in germs that make consumers resistant to the drugs, potentially threatening the lives of millions of people. 

“To allow such a massive increase of these drugs in agriculture is a recipe for disaster,” said Steven Roach, a senior analyst for the advocacy group Keep Antibiotics Working, in an interview with the New York Times. “It’s putting the needs of the citrus industry ahead of human health.”

Advocates also point out that the new rule ignores years of work by federal agencies and environmental groups to curtail the rampant use of antibiotics in agriculture and human medicine that harm our health.

Every year, drug-resistant infections claim the lives of 23,000 Americans and sicken two million more, according to the CDC. The agency considers drug resistance “one of the biggest public health challenges of our time. ”

The CDC has already logged more than 1,000 cases in the U.S. of drug-resistant tuberculosis — the chief infection that streptomycin treats.

Meanwhile, the threat is only growing as more bacteria mutate.

The United Nations says drug-resistant infections could claim 10 million lives globally by 2050, surpassing cancer as a leading killer, as the New York Times reported.

The risks of spraying antibiotics on crops

Advocates opposing the FDA rule assert that  spraying antibiotics, such as streptomycin, will pollute food, soil and drinking water, spurring the growth of antibiotic-resistance pathogens.

These warnings hold real world implication.

Recently, the Netherlands authorized widespread spraying of fungicide by tulip farms. The result was a surge in cases of the treatment-resistant fungal lung infection known as aspergillosis. It was noted to have affected people with already-weakened immune systems.

For a while, those aware of the outbreak couldn’t understand what was causing it. According to The Atlantic, physician and microbiologist Paul Verweij was the first person to discover the link between the disease outbreak of aspergillosis and the affected patients’ whose bodies were resistant to the azoles antibiotic.

After further investigation, it was discovered that agricultural azoles had contributed to this antibiotic resistance.

Because of cases like this, the European Union is among the groups of nations that have outlawed the use of certain antibiotics, including streptomycin, in agriculture.

Brazil also has banned spraying streptomycin, even though its orange growers are battling the same citrus greening disease as their counterparts in this country.

Antibiotic research sponsored by industry groups

The potential toll of streptomycin use in agriculture on humans and wildlife is uncertain due to the lack of large-scale research. The few studies that are available were industry sponsored. The international science journal, Nature, however, notes “the death of publicly available data is alarming, particularly in the face of a massive scale-up in application that could set a global precedent.

Ignoring the lessons of Roundup

By pushing forward with the new rule despite forceful objections to it, advocates say the EPA is ignoring the long, troubled history of chemical overuse in agriculture.

They point to the example of glyphosate, the active ingredient in the weedkiller Roundup. The Orlando Sentinel reports that overuse has fueled the growth of glyphosate-resistant superweeds across millions of U.S. acres.

But while Roundup’s impacts have been observed and condemned, the effects of streptomycin use in agriculture have yet to be seen. Time will tell.