Occurrence and fate of antidepressants in the aquatic environment: Insights into toxicological effects on the aquatic life, analytical methods, and removal techniques

ABSTRACT

The consumption of antidepressants has increased on a global scale. These medications are frequently prescribed to treat mental health-related disorders and their usage is expected to rise in the future because the COVID-19 pandemic has intensified these problems significantly. These compounds have recently been detected in wastewater treatment plants and surface waters, raising concerns about their potential impacts on the envi-ronment. In this regard, the current review aims to critically evaluate the available information on the worldwide consumption of antidepressants, their occurrence, possible toxicological effects on aquatic organisms, and removal techniques. Several analytical methods for the extraction and quantification of antidepressant com-pounds have also been discussed. Additionally, risk quotients (RQs) have been estimated which indicates that sertraline posed the highest risk (RQ 4.88) to the aquatic life followed by citalopram (RQ 1.55) and bupropion (RQ 1.12). It was observed that the aquatic organisms encountered behavioral, physical, cardiovascular, and reproductive changes after being exposed to antidepressant compounds. Some of these compounds have been satisfactorily removed (>85%) using a sequencing batch reactor with aerobic granulation of sludge. Physico-chemical processes such as photocatalysis, photochemical oxidation, and electrocatalysis exhibited more than 90% degradation efficiency in most cases. Moreover, integrating two or more physicochemical processes improved the treatment efficiency further. This study may help researchers to understand the threats posed by antidepressants to the environment and result in the development of innovative technologies for their removal.