Authorities say the counterfeit goods were ready for sale to unsuspecting medical workers.
PDF: Information provided by 3M on some common signs of counterfeit mask
Zhi Zeng, 33, of Dyker Heights, Brooklyn, was arrested for allegdly managing the "dirty, dusty, Long Island City warehouse" where the masks were seized.
"These items were packed in boxes, piled high on more than 100 shipping pallets," Katz said.
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Other warehouse workers remain under investigation.
"We believe this to be one of the largest single seizures of counterfeit masks since the pandemic began," Katz said.
The masks were being sold to health care workers, who believed they were purchasing and using genuine 3M masks.
Instead, the substandard masks were imported from overseas, or produced in the warehouse, and repackaged with 3M branding.
"3M is aggressively fighting counterfeiting of our critical products needed by health care and front line workers during the pandemic," 3M said in a statement. "We are grateful to the Queens District Attorney's Office investigation, which has resulted in getting counterfeit respirators out of circulation. 3M recommends only buying products from authorized distributors."
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The masks were being sold in a price range from $2.95 to $3.25 each. The suggested price of the actual 3M masks is $1.27 each.
3M also released helpful information on how to determine if a mask is counterfeit.
Katz said conditions were not sanitary for making masks used as PPE.
"You end with a box that looks very authentic and looks like it was sent by 3M," Katz said. "There is no reason to believe upon observation that these are not the real 3M masks."
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At least one health care system in the south paid more than $700,000 for the fake masks, and Katz said there are believed to be many more currently in the hands of health care workers.
Katz said investigators do not know if the masks provide any protection to the wearer.
"We don't know," she said. "We do know these masks were not made by 3M. We do know they put themselves out as N95 masks. We do know they were packaged fraudulently in different boxes that are not in fact from 3M. We are analyzing the masks now to see whether or not they provide any protection or all the protection, but there is no way of knowing that from looking at it...For all intents and purposes, they look like the real thing. They feel like the real thing. The lot number is fraudulent on here, but you would have no way of looking at it."
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