Who should I contact in Ohio regarding coworker problems? It is a problem with harrment by a drug user.?

This problem has been occurring in the hospital in which my daughter works. Numerous women are being seriously harred by a male coworker. Going to supervisors & human resource personnel has not worked, as this coworker supplies drugs to the supervisor & human resource worker. How can my daughter and her friends safely and annonimously blow the whistle on this individual without being retaliated by this drug dealer? Who can they safely contact for help? Thanks.