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The U.S. Environmental Protection Agency (EPA) may soon approve a new nano-scale, gene-silencing biopesticide for commercial use — the agency will close its public comments window on the issue on Friday, Oct. 13.
The pesticide’s active ingredient, ledprona, is made of double-stranded RNA (dsRNA) that silences a gene that the Colorado potato beetle needs to produce a key protein. With the gene turned off, the insect cannot function normally and dies.
Should the biopesticide be approved, it will be the first sprayable dsRNA pesticide in the world allowed to be commercially sprayed on plants.
GreenLight Biosciences, the Massachusetts-based biotech firm marketing the ledprona-containing pesticide under the name “Calanthra,” claims dsRNA technology — commonly called RNA interference (RNAi) technology — provides an advantage over chemical pesticides used on potato crops because it quickly degrades in the environment and leaves no detectable residues on food, soil, water or in the atmosphere.
But pesticide experts said there’s insufficient data to show the biopesticide is safe.
André Leu, author of “The Myths of Safe Pesticides” and “Poisoning Our Children,” said there is a “massive lack of evidence-based data” showing RNAi pesticides are safe for human newborns, fetuses, young children and children going through puberty. These are times when people are the most vulnerable to toxins, hormones, and changes to gene expression.”
The EPA in May gave ledprona an experimental use permit (EUP) valid through 2025, so GreenLight Biosciences could test Calanthra in 10 states, noting that the Colorado potato beetle is a “major pest” of potato crops grown in the U.S.
“If left uncontrolled, CPB [Colorado potato beetle] will eat and destroy the leaves of the plant,” the EPA said.
The EPA charged GreenLight Biosciences with notifying the agency throughout the EUP of “any findings from the experimental uses that have a bearing on safety.”
According to Center for Food Safety (CFS), a nonprofit advocating for food safety, animal welfare and environmental justice, the EPA is “jumping the gun” and needs to wait to analyze the data collected during the EUP period.
CFS is urging citizens to tell the EPA to hold off on registering ledprona for commercial use until all the data from the EUP timeframe is “thoroughly analyzed and the product is found safe to use.”
Jaydee Hanson, CFS’ policy director, told The Defender, “What we have is a situation where the EPA is, in our opinion, skirting the legal requirements of the major pesticide act, FIFRA [Federal Insecticide, Fungicide, and Rodenticide Act].”
Hanson noted the EPA is moving ahead to allow the pesticide to be sprayed on farms across the country, having seen “less than the data required for a conditional registration,” he said.
The EPA “has it backwards,” Hanson said. “One of my uncles, who used to be the commissioner of agriculture in Idaho, would be saying, ‘What? This is not the way to do it.’”
Rather than proposing registration so hastily, Hanson said, the EPA should let the EUP run its course, then analyze the data collected during that time and afterward open a public comment session about possibly making the pesticide available commercially.
The EPA on Sept. 27 released a human health risk assessment report on ledprona, claiming, “There will be no unreasonable adverse effects to humans for the proposed commercial use registration if both a respirator and protective eyewear are added as required personal protective equipment on the product label.”
But Hanson said, “We haven’t seen any data on the EUP yet.” He added that it’s currently unclear whether the company has started spraying yet at all 10 experimental sites, and it will take multiple growing seasons to collect adequate safety data.
Critics call for moratorium on RNAi pesticides until safety questions are answered
“With the allowance of gene-manipulating RNAi pesticides, EPA is repeating a pattern of allowing uncertainty that has historically resulted in serious unexpected and uncontrolled hazards, despite the availability of organic practices and products that are currently available.
“The agency has failed to fully evaluate the fate of genetic material and its degradation products on nontarget species and the likely potential for indiscriminate poisoning.”
“We are calling for a moratorium on RNAi pesticides until these questions can be fully answered,” Feldman said.
A spokesperson for GreenLight Biosciences told The Defender that “multiple studies” and the EPA “have confirmed that Calantha has no effect on people, pollinators, or other non-target organisms.”
The spokesperson did offer detailed information about the studies.
Leu told The Defender ledprona should be banned until there is “clear evidence” that it is safe for people. He said:
“Many living species, including humans, share an enormous amount of similar DNA and genes. RNA can adversely affect these off-target genetic sites.
“Despite the industry claims, RNA can interfere with gene expression in many species, causing a variety of unintended adverse health and reproductive effects such as cancers, metabolic disorders, hormone disruptions, organ damage, and numerous other diseases.”
Nanotechnology expert: EPA should convene scientific review panel on RNAi pesticides
Hanson — an expert in nanotechnology and synthetic biology who co-chairs the U.S. nanotechnology taskforce of the Transatlantic Consumers Dialogue — said the EPA should convene a scientific review panel on RNAi pesticides.
The agency did this for nanosilver when first approving it as a pesticide, he said. “There’s no reason they couldn’t do it for nano-encapsulated pesticides,” he added.
GreenLight Biosciences hasn’t specified the details of its product “but one has to assume it’s a nano-encapsulated RNAi because otherwise it would break down too fast,” Hanson said. “This is why, for example, many of the RNAi vaccines people took for COVID-19 were nano-encapsulated.”
The scientific review panel process isn’t difficult, he said. It consists of conveying a panel of experts, including scientists who have expertise in the area, for two or three days to review the pertinent scientific literature and hear public testimony.
The EPA appears to be ignoring such reports, Hanson said.
Moreover, the agency needs to do the tests required by the type of registration it’s proposed to give ledprona.
For instance, he pointed out that the EPA has not yet done studies assessing ledprona’s potential impact on birds and fish. Yet the EPA may allow it to be sprayed both on the ground and aerially by plane.
“We don’t know how long it’ll live in soil, how far it’ll go, or the effects it’ll have on other species,” he said.
Rushing the approval process makes it look like an ‘inside job’
Hanson said it’s “basic human health and environmental health work” to test a new product in small batches for a period of time “to get an idea of how well will this perform.”
So by not allowing scientists to review the data collected during the EUP, the EPA has “thrown precaution to the wind.” He said, “I’m not saying this stuff [ledprona] is awful; the problem is we don’t know.”
And to rush the “very first experiment” of RNAi pesticides “looks almost like an inside job where the folks [from GreenLight Biosciences] … know some of the EPA people,” he said.
Hanson quickly added that he was not making that accusation but, rather, thinks that a mentality of “gee whiz, look what we can do” is prevailing over “good science.”
He added that if you test it in small batches and it has negative effects, it’s pretty easy to stop. “But if you spray it everywhere that grows potatoes, then that’s a different story.”
Prior pesticides proven harmful to kids’ health
Though data on RNAi pesticides is lacking, recent research has shown other kinds of pesticides to have serious impacts on kids and young adults.
A systematic review published last month in Pesticide Biochemistry and Physiology found several pesticides were linked to insulin resistance.
Insulin resistance is associated with metabolic disorders like diabetes, obesity, chronic kidney disease and hypertension, which are on the rise in young people.