Unintended consequences after disposing of a drug into sewage:
(1) release into the environment
(2) promotion of antibiotic resistance
(3) interference with sewage digestion
Some cities have 2 types of sewage - one for human waste and one for rain runoff. A sewer used for rain runoff may be untreated or minimally treated. Disposal of a drug into a sewer meant for rain runoff is more likely to result in drugs entering the environment.
Compounds that may be hazardous when released into the sewage system:
(1) antibiotics
(2) disinfectants
(3) chemotherapeutic agents
(4) radiographic contrast agents
(5) anesthetics
Sources that could generate a large amount of pharmaceuticals into the sewage system:
(1) pharmaceutical companies
(2) pharmacies
(3) hospitals
Problems that can occur in the home:
(1) obstruction of a sewage pipe by a drug mass (similar to a pharmacobezoar) when a large number of pills are disposed of
(2) disposal into a septic tank
