PORTLAND, Ore. — You may rely on a neti pot to flush out your nasal passages this winter, but you need to be careful about what kind of water you use.

We set out to Verify: Can you using tap water in your neti pot cause a deadly infection?

The FDA says tap water can contain low levels of organisms, like bacteria, protozoa and amoebas. These organisms can be safe to swallow, but they're extremely dangerous inside your nasal passages.

And even if you use a filter for your tap water before putting it in the neti pot, that's still not enough to get rid of those organisms.

The FDA recommends you use distilled or sterile water available to buy at stores, boiled and cooled tap water (boiled for 2-3 minutes), or water passed through a filter specifically designed to block harmful organisms.

In fact, many net pot kits come with a saline or saltwater solution that needs to be mixed in with water before you put it inside your neti pot.

You should also make sure to deep clean your neti pot after each use.

Improper usage of a neti pot can lead you to contract potentially deadly amoebas. A woman in Seattle used tap water in her neti pot, and suffered a seizure about a year later.

What doctors thought was a tumor in her brain ended up being amoeba "all over the place just eating brain cells," Dr. Charles Cobbs with the Swedish Medical Center in Washington told the Seattle Times.

Doctors eventually learned the bacteria she contracted was balamuthia mandrillaris, a slow-moving amoeba that can take weeks or months to cause death.

According to figures obtained by the Times, there have been 109 cases of balamuthia in the US between 1974 and 2016; 90 percent of those patients died.

We can Verify: Using tap water in your neti pot can lead to a deadly infection. It's rare, but it certainly is possible.