New research has revealed that typical municipal wastewater treatment plants are ineffective at removing fluoxetine and other common pharmaceutical compounds found in wastewater discharge. The lack of an effective removal strategy leads to these compounds being discharged into lakes, rivers, and streams, where they can pose a serious risk to aquatic flora and fauna.
Describe in the journal PLOS One, the work including testing samples from six wastewater treatment plants in Poland to investigate their efficacy at removing more than a dozen common pharmaceutical compounds. To quantify the discharge, the team measured the levels of drugs coming into the plant, as well as how much was discharged in treated water and sludge.
Ultimately, the team found that all six plants released pharmaceuticals into the environment with naproxen and salicylic acid being the only compounds effectively removed during treatment. Further analysis showed that the water treatment process increased levels of fluoxetine, diclofenac, and carbamazepine.
Of greatest concern to the team, fluoxetine and Claritin pose a high risk to aquatic organisms due to their ability to disrupt hormone signaling at concentrations the team found in water. Previous work has demonstrated that while some drugs will eventually break down in the environment, most are persistent and remain active at extremely low concentrations.
The results of the study add to a growing body of evidence which demonstrates that conventional water treatment methodology is ineffective at removing many common pharmaceuticals, making wastewater treatment plants a common source of pharmaceutical pollution.