After painkiller costs rose several hundred thousand dollars on his company's prescription health plan, the human resources director of a Michigan auto parts factory discovered his company was "a prime target for people to deal" after hiring a risk management firm, Crain's Detroit Business reports.

Tony Behrman hired the Ann Arbor-based risk management firm Pinkerton after its insurance plan's prescription costs climbed so steeply that it amounted to "probably a $500 per head increase," he said.

"The pills aren't that expensive," he said. "The spike didn't make any logical sense to me."

Pinkerton placed an undercover agent onto the factory floor of Nexteer Automotive Corp.'s Saginaw Steering Gear complex. Within hours, the agent was approached to buy prescription opioids, Crain's reports.

Pinkerton's managing director, Eric Rose, says opioid investigations have overtaken the firm's internal theft investigations over the past 18 months. One scam he has seen is linked to workers' compensation, he said.

"A guy will fall off a forklift and will get a script for 50 Percocets. We recently had a case where six employees would alternate injuries to get scripts filled and supply each other. Two of the six then started selling (the pills) on the side," Rose said.