◆ EPA targets sellers of fake virus cleaners that are flooding the market.

WASHINGTON — The Environmental Protection Agency warned Friday that disinfectants and sanitizers falsely claiming to protect against the coronavirus are flooding the market and threatened legal action against retailers that sell unregistered products.

A necklace containing chlorine dioxide, a bleaching agent, that supposedly sanitizes the wearer is among the bogus products, along with a sticker that claims to provide 30 days of protection against the coronavirus. A range of unregistered disinfectants, sprays, air purifiers and wipes also falsely assert they prevent infection from the virus.

A senior administration official said the agency is seeing a “huge” spike in such products, which have not been tested or registered with the EPA. While such products might not be harmful, the official said, they offer a dangerously false sense of protection that could deter social distancing and promote the spread of COVID-19.

EPA Administrator Andrew Wheeler met by teleconference with online retailers to warn them against selling unregistered products that claim to be effective against the virus.

Officials said the agency intends to issue enforcement measures that require companies to halt sales of fake products. It also is coordinating with the Justice Department “to bring the full force of law” against anyone who continues to do so.

“We will work diligently to ensure that consumers have access to EPA-approved and verified surface disinfectant products; products that we know to be effective against the novel coronavirus,” Wheeler said in a statement.

The EPA specifically targeted a Japanese-made product called Virus Shut Out, which is a card containing chlorine dioxide worn around the neck on a lanyard. Those and other so-called “sanitization cards” are on sale on eBay and by retailers on Facebook. Last week, the agency announced it had prevented shipments of it from entering U.S. Pacific ports under federal pesticide laws.