A Callender couple has been arrested on felony drug offenses after police said the two tried to purchase too much pseudoephedrine at an Ames retailer.

Milten William Ringgenberg, 48, and Brenda Sue Ringgenberg, 32, were charged Wednesday night with possession of pseudoephedrine with intent to manufacture methamphetamine, and possession of lithium with intent to manufacture methamphetamine, both of which are Class D felonies. The charges could bring sentences of up to five years and fines of up to $7,500.

The couple could face additional charges based on the equipment found at their residence, said Capt. Gary Foster, chief deputy for the Story County Sheriff’s Office.

The Central Iowa Drug Task Force received a phone call from security personnel at the store, who said the Ringgenbergs had purchased more pseudoephedrine than allowed, he said. Police declined to release the name of the retailer.

Foster said officers followed the car out of the parking lot and conducted a search of the vehicle, discovering lithium and pseudoephedrine.

The origin of the lithium is unknown, he said.

The police then obtained a search warrant for the couple’s residence, which is standard procedure, Foster said.

“There was basically a meth lab in the residence,” he said.

Foster said the Ringgenbergs were released from Story County Jail on Thursday on pretrial release.

The Ringgenbergs could not be reached for comment.

Scott Sitzman, Target pharmacy manager, said to combat the methamphetamine problem in Iowa, a new law is planned to go into effect on May 21.

The law requires retailers to store all products containing pseudoephedrine behind a counter and keep a log of sales. Sitzman said customers will need to provide valid identification.

“Without a driver’s license or state ID, we won’t be able to sell the pseudoephedrine,” he said.

Story County Supervisor Wayne Clinton said he thinks the law will be a useful aid to law enforcement because it closes a loophole allowing people to purchase the maximum amount of pseudoephedrine at multiple locations.

“This would aid the law enforcement and prosecuting attorney in putting together a better case against a meth manufacturer because they would have access to the dates and quantities of pseudoephedrine purchased by the person,” Clinton said.