A third Colorado library has shut down due to methamphetamine contamination less than a month after the first closure in the state.
The City of Littleton announced the closure of the Bemis Public Library on Wednesday after "elevated levels" of meth were found in bathrooms on the main and lower levels of the building.
Bemis Public Library is now closed to the public while testing is done throughout the building and "professional decontamination" is conducted, according to the city.
It is unclear how long the restrooms have been contaminated.
"The safety of our employees and library patrons is our first priority," Littleton City Manager Jim Becklenberg said in the announcement.
Tests conducted on Jan. 13 determined that methamphetamine contamination was present in exhaust fans of the men's and women's restrooms on the main floor, as well as the gender-neutral restroom on the lower level, according to the City of Littleton's website.
The remainder of the library will be tested while it is closed to the public, the city said, adding that "remediation will begin as soon as comprehensive testing is complete."
Two other Colorado libraries have been forced to temporarily close their doors in the last month over the same issue.
In a letter addressing the contamination at Boulder Public Library, Boulder County Public Health said studies show "very low" health risks are associated with secondary exposure to methamphetamine residue in public spaces — compared to exposure in places where the drug "is or was manufactured or consumed regularly."
The Englewood Public Library said drug activity at the library was reportedly on the rise in the months leading up to the temporary closure, NPR reported.
However, staff at Bemis "have not witnessed active signs of drug use in the library," according to the City of Littleton.
Never miss a story — sign up for PEOPLE's free weekly newsletter to get the biggest news of the week delivered to your inbox every Friday.
The American Library Association told NPR that the organization is "unaware of this issue occurring anywhere else in the country, currently or in recent years."
Methamphetamine use has been on the rise nationwide in recent years. The National Survey on Drug Use and Health (NSDUH) estimates about 667,000 people ages 12 and older in the United States used methamphetamine in 2016, according to Boulder County Public Health.
At the same time, Boulder County has seen "a dramatic increase" in methamphetamine-affected properties.
"We definitely have evidence that there's more meth use," said Chelsea Shover, assistant professor-in-residence at the UCLA David Geffen School of Medicine, according to NPR.
Shover said methamphetamine use is even up "in parts of the country where it was previously pretty rare."
If you or someone you know is struggling with substance abuse, please contact the SAMHSA helpline at 1-800-662-HELP.