Aeration May Remove SSRIs From Landfill Leachate

Aeration treatment may be an effective means of removing selective serotonin reuptake inhibitors (SSRIs) from landfill leachate before they reach the environment, a new study finds.

SSRIs, generally used as antidepressants, are often not fully metabolized in the human body. When excreted, these drugs can end up in municipal sewage systems and landfill leachate. If the leachate enters the groundwater, the drug compounds can be released into the environment and have negative impacts on other living organisms.

A team of Norwegian researchers set out to gain a better understanding of what happens to these compounds during aeration, and whether they can be removed before leachates enter the environment.

Aeration is used to purify the liquid within a pond or lagoon before it is released into the environment. However, not all pharmaceuticals react in the same way to aeration, and its effects on SSRIs within landfill leachate is poorly understood.

Over a five-day period, the researchers mimicked the process used to treat landfill leachate using samples containing five different SSRIs — citalopram, fluoxetine, paroxetine, sertraline and fluvoxamine — and three of their metabolites. The concentration of the SSRIs in water samples was measured at the beginning and the end of the study period and compared to the total amount of SSRIs that would be present if no reduction had occurred. In all of the samples, the concentration of the SSRIs was reduced by more than 80 percent. Fluvoxamine and citalopram were removed entirely from both high- and low-concentration samples.

The samples were also tested for their known metabolites, the compounds produced when these SSRIs are broken down in the body. Only one could be detected, suggesting that aeration may break down the compounds differently than human metabolism.

The results of such studies could inform more sophisticated water treatment systems to prevent the negative environmental impact of pharmaceutical pollution.

Photo credit: variety of medicines via Shutterstock.