The Knox County Health Department announced Monday it is halting distribution of state-purchased masks after concerns were raised about an anti-microbial solution used to coat the fabric.
According to KCHD, the department will not hand out the Renfro-manufactured masks until more information is known about the coating.
The Hamilton County Health Department made a similar move Saturday, saying the masks are coated in Silvadur, an anti-microbial substance commonly applied to fabrics to reduce odor-causing bacteria.
The HCHD said only trace amounts are applied to the masks and will diminish after each wash, but asked the public to refrain from using and distributing these masks until more information is made available about the application of Silvadur.
According to the EPA, Silvadur is approved for use in non-food contact uses such as socks, other apparel, bedding, carpets, brushes, wiping cloths, tents, and more.
The Renfro Corporation is a global sock company that switched its assembly line in Cleveland over to produce nearly 5 million masks purchased by Tennessee. The masks were sent to all 95 health departments across the state to be distributed in order to provide people with free masks to help prevent the spread of COVID-19.
KCHD said it has distributed more than 143,000 of the masks. It continued to urge people to wear face coverings or other masks.