On May 29, 2025, the EPA proposed to register one technical and two end-use products containing the new active ingredient Vadescana, a double-stranded RNA (dsRNA), for control against varroa mites (Varroa destructor) in honeybee hives.
These mites are parasites that feed on honeybees and are responsible for transmitting several honeybee viruses. Left untreated, varroa mites often kill the hive.
“Varroa mites are a national threat to bee colonies and in turn to farmers with crops dependent on pollination services provided by bees, and ultimately to food security in the United States,” states an Agency news release. “EPA is prioritizing pesticide applications that target Varroa mites to provide beekeepers with a variety of tools to combat this pest.
“No risks of concern to human health or the environment were identified, including risks to federally listed species under the Endangered Species Act (ESA). When used according to the label, risks to bees are not expected because Vadescana is highly specific to the targeted gene within Varroa mites.”
Vadescana was developed by Massachusetts-based GreenLight Biosciences, according to Capital Press, which notes, “The USDA has described the insecticide as ‘paradigm-shifting technology’ that could displace more toxic pesticides.”
“GreenLight will sell the insecticide under the brand name Norroa. The company will have to get state-level approvals before the product becomes available, GreenLight spokeswoman Catie Lee said,” Capital Press continues.
The product will be sold in pouches that allow beekeepers to peel back a sticker before placing a pouch in a hive. The bees will store the insecticide as food, which the mites will eat.
As Capital Press explains, “The insecticide inhibits a protein essential for reproducing. The USDA submitted enthusiastic comments last year when EPA was evaluating the insecticide. ‘Over time, we believe the use of vadescana is likely to displace the use of compounds that are relatively more toxic for bee colonies,’ USDA pest management policy director Kimberly Nesci wrote.”
In March 2025, a new varroacide product containing l-glutamic acid, an active ingredient that hasn’t previously been included in registered products for use in beehives, was also registered by the EPA. It also intends to register another product containing oxalic acid, a slow-release varroacide within beehives, by July 2025. Together, these four end-use products are expected to provide new tools, including novel active ingredients, to control varroa mites in beehives.
The Agency has developed informational videos to provide resources for pesticide decision-makers and educate the public about integrated pest management options and legal options of pest control for varroa mites, small hive beetles, and wax moths. It also funded the development of interactive training modules to help pesticide applicators conduct bee kill investigations.
See the EPA varroa mite pesticide product webpage for more information.