(EL PASO COUNTY, Colo.) — At the end of October, multiple homeowners and neighbors living in eastern El Paso County received a letter in the mail about their drinking water.

It stated that the Cherokee Metropolitan District had undergone voluntary testing to look for polyfluoroalkyl substances (PFAs).

These are also known as forever chemicals, which can cause long-term health issues if exposed to them for a long period of time. According to the Colorado Department of Public Health and Environment (CDPHE), there is strong evidence that certain PFAs:

Increase cholesterol

Impact the immune system

Decrease infant birth weight

Cause changes in liver function

Cherokee detected perfluorooctanoic acid (PFOA) at 8.7 parts per trillion and perfluorooctane sulfonic acid (PFOs) at 2.8 parts per trillion at two locations out of 15 sampled locations during one testing period.

A homeowner living in Colorado Springs who wished to remain anonymous told FOX21, “Getting this letter was very troubling. Some of my friends have this water in the neighborhood, are pregnant and elderly, and they have a lot of health concerns.”

Amy Lathen, general manager for the Cherokee Metropolitan District, spoke with FOX21 on these concerns.

“All we do here day in and day out is to make sure that our water is uninterrupted and safe to drink,” Lathen said.

The Environmental Protection Agency (EPA) proposed limit for both is 4.0 parts per trillion. Cherokee said one part per trillion could be compared to diluting one half teaspoon into 1,000 Olympic-sized swimming pools.

“These numbers are just so tiny,” Lathen said. “It’s one second out of 32,000 years.”

According to Cherokee, the water is considered safe to drink. They said they sent out the letter because exposure to PFAs over a lifetime could be hazardous to health.

But there are concerns that the forever chemicals are in the water at all.

“I have small children,” the anonymous Colorado Springs resident said. “And, on the letter they sent home, it says if you have children under the age of five that you need to be cautious of how much they’ve been exposed to it. And if you’re pregnant, that there should be a lot of concern. So, yes, I’m very concerned about it.”

The homeowner said she called a reverse osmosis company to give her an estimate on a water filtration system, and they treated her water.

“They said that the levels are the same, of which the Widefield area was contaminated, and they said that this is another disaster and that we shouldn’t be drinking the water,” she said.

Cherokee said it is working on designing a new water treatment facility to completely eliminate the presence of any PFAs compounds. Cherokee said since PFAs are already present in fast food packaging, makeup, nonstick cookware, clothing and other products, it wants to make sure consumers don’t also have to worry about it coming from their water.

“We do believe these proposed limits are so, so conservative that we will ultimately be building a water treatment facility in order to reduce this to zero,” Lathen said.