Louisville-area residents who have unneeded or expired prescription medications can have them properly disposed of this week.Louisville Metro Government is sponsoring its fifth annual pill toss. From Thursday through Saturday, anyone with unneeded pills can go to one of six sites around the city and give their drugs to the police for proper disposal.Mayor's spokesperson Chris Poynter says improperly disposing of drugs can be damaging to the environment."Some people, once their prescriptions are no longer needed or they run out, they throw them in the toilet and flush them down the drain," he says. "That goes directly into our sewer system and into our water system. It can contaminate drinking and groundwater."Poynter says the pill toss will also help keep the medications out of the hands of drug abusers.See the list of pill toss locations.