In early October, Contact 6 visited five local stores and took samples from the masks on display.
Contact 6 swabbed the inside of Halloween masks for germs. Some of the masks hung in grand displays while others were piled in bins.
In all, Contact 6 took samples from 16 masks. They brought the samples to Accelerated Analytical Labs for testing.
The results may haunt you for a while.
"There's a lot of different growth," said Thomas Hirsch, laboratory supervisor. "We saw pretty high levels of bacteria and mold."
"That could definitely be a vector for spreading cold and flu in this season, for sure," Hirsch explained.
One mask registered positive for fecal matter. Another mask contained bacteria that causes urinary tract infections.
Contact 6 showed the results to Krassi Hristova, an associate professor of Biological Sciences at Marquette University.
"Actually, I'm surprised and a little bit concerned," Hristova said.
She said she's most concerned by the presence of some opportunistic pathogens, which could harm a person with an already weakened immune system.
"Those are bacteria that you really don't want to see, and especially not be in contact with small kids for example," Hristova said.
Among other findings -- bacteria that can cause cavities, foodborne illness, vomiting and diarrhea, eye infections and central nervous system infections.
Hristova said the mold could be a problem for someone with allergies or asthma. She said she has a theory about how mold ended up in the masks.
"My guess is that it's from storage and any high humidity environment, it`s promoting the growth of the mold," she explained.
The results across the board were pretty much the same no matter where Contact 6 shopped. However, there was one exception.
"The Goodwill masks were the cleanest looking, overall on average," Hirsch revealed.
If you find this all horrifying, don't worry, there is an easy solution here. Use a disinfectant wipe inside your mask before you wear it. After all, your mask should be scarier than what's inside it.