A study by the U.S. Geological Survey in 1999-2000 concluded that streams were highly contaminated by pharmaceuticals as a result of improper drug disposal by households. The latter typically dispose of drugs that have long sat in the shelf by flushing them down the drain. While this practice keeps long-expired drugs out of children’s reach, it channels potentially harmful pharmaceuticals instead to municipal water tables.
This practice impacts not only the local ecosystem but more alarmingly, the local population’s potable water source as well. In 2008, findings by the Associated Press claimed that 41 million Americans were drinking drug-contaminated water, even the ones that came bottled. (While bottled water is generally treated, it is not tested for pharmaceuticals, so the effectiveness of the treatment is unknown.)
As improper drug disposal could re-channel expired and unused pharmaceuticals back into the household water stream, it is critical that the drugs be rendered unusable and irretrievable. (There are several ways in which drugs leach back into water sources, one of which is through human excretion.) Even municipal water treatment systems are not equipped with treating waste water, which puts the public at risk for exposure to potentially harmful pharmaceuticals via the tap.
Pharmaceuticals also leached into water tables that are used for raising farm animals, as livestock has been found to consume approximately 11,000 metric tons of antimicrobial medications annually. Exposure of animals to antibiotics also increases the resistance of humans to similar medications because livestock make up the bulk of their food source. As a result, improper drug disposal contaminates not just the local human population’s drinking water but also their food.
Incineration and disposal in landfills are not only costly, they also tend to be ineffective and create opportunities for diverting drugs to unauthorized uses,which could result to preventable overdose and other drug-related incidents. Without rendering unused and expired medications totally irretrievable and unusable, the overall social cost of improper drug disposal is more than just environmental.