Americans turned in 647,211 pounds, or 324 tons, of expired and unwanted medications for safe and proper disposal during the most recent National Prescription Drug Take-Back Day on October 26. The event was led by the Drug Enforcement Administration (DEA).

According to the DEA, 5,683 sites participated in the event in every state, the District of Columbia, and U.S. territories. It was the second-largest collection of medications in seven Take-Back Days. More than 3.4 million pounds of medication have been removed from circulation as a result of the seven events.

“The American people have once again responded to the National Prescription Drug Take-Back Day event, and we thank them for participating in this effort to battle prescription drug abuse,” DEA Administrator Michele M. Leonhart said in a news release. “These take-back events highlight the problems related to prescription drug abuse and provide a unique and meaningful service to our citizens. While we continue to finalize a uniform system for prescription drug disposal, we will continue to sponsor these take-back opportunities and give Americans the opportunity to contribute to the solution.”

A majority of abused prescription drugs are obtained from family and friends, including from the home medicine cabinet, according to the DEA. The take-back events are designed to give people an environmentally friendly way to dispose of their medications, without flushing them down the toilet or throwing them in the trash. In recent years, medications have been found in the nation’s water supplies, and have been retrieved from the trash by people who want to abuse or sell them, the DEA noted.