LONGMONT, Colo. -- Longmont police evacuated a six unit apartment building Friday after tests conducted by the Boulder County Health Department showed contamination from a suspected meth lab had seeped into the entire building.

That contamination forced several tenants out of their homes and led police to quarantine seven pets.

"We decontaminated one of the dogs at the scene," said Longmont police Commander Tim Lewis. "The other dog, five cats and a parrot were taken to the Longmont Humane Society."

Police say it's becoming more common to quarantine pets from living units adjacent to suspected meth labs.

"We've seen short-haired dogs with chemical burns and chemical sores," Lewis said.

The pets taken from the building on the 1900 block of Meadow Drive are being cared for under the humane society's Safe Keep program.

"The whole point of the program is to keep the animals safe, until their owners get back on their feet, get new homes or do whatever they need to do," said Clay Evans of the Longmont Humane Society.

Late Monday, city officials posted another sign declaring the building and adjacent garage a public nuisance. All windows and doors have been boarded shut until the owner and his insurance company can come up with a plan to decontaminate the structure.

"We've seen some cases where the owners have had to strip the paint off the walls," Lewis said. "In other cases, where the contamination is severe, owners have had to strip everything down to the ceiling, floor and wall joists."

"They've made a mistake. That's all I can say," Stephen Derr told 7NEWS.

Derr is the man police took into custody following the meth lab bust. He said the chemicals police recovered are household items he uses to maintain the property for the owner. He denied that it was a meth lab.

Derr's girlfriend, Beth Bartleson, said the animals weren't in any danger.

"I don't think so,” she said. “I never had any health problems with them."

When asked about the quarantine and Safe Keep program, Bartleson said, "I think it's a great program. I worked at a vet clinic for 7 years. If animals are in danger, it's a great thing to get them out and cleaned up as best they can."

Evans said all the animals in quarantine are doing well.

Lewis said the animals will be given back to their owners after they find new places to live. He said outreach workers are trying to help the tenants do just that.