Abstract

Pharmaceuticals are emerging as environmentally problematic compounds. As they are often not appropriately removed by sewage treatment plants, pharmaceutical compounds end up in surface water environments worldwide at concentrations in the ng to mu g L-1 range. There is a need to further explore single compound and mixture effects using e.g. in vivo test model systems. We have investigated, for the first time, behavioral effects in larval zebrafish (Danio rerio) exposed to a binary mixture of an antidepressant drug (citalopram) and a synthetic opioid (tramadol). Citalopram and tramadol have a similar mode of action (serotonin reuptake inhibition) and are known to produce drug-drug interactional effects resulting in serotonin syndrome (SS) in humans. Zebrafish embryo-larvae were exposed to citalopram, tramadol and 1:1 binary mixture from fertilization until 144 h post-fertilization. No effects on heart rate, spontaneous tail coiling, or death/malformations were observed in any treatment at tested concentrations. Behavior (hypoactivity in dark periods) was on the other hand affected, with lowest observed effect concentrations (LOECs) of 373 mu g L(-1 )for citalopram, 320 mu g L-1 for tramadol, and 473 mu g L-1 for the 1:1 mixture. Behavioral EC50 was calculated to be 471 mu g L-1 for citalopram, 411 mu g L-1 for tramadol, and 713 mu g L-1 for the 1:1 mixture. The results of this study conclude that tramadol and citalopram produce hypoactivity in 144 hpf zebrafish larvae. Further, a 1:1 binary mixture of the two caused the same response, albeit at a higher concentration, possibly due to SS. (C) 2019 The Authors. Published by Elsevier Ltd.

Keywords

Zebrafish embryotoxicity; 5-HT; SSRI; Synthetic opioid; Serotonin syndrome

Published in

Chemosphere
2020, Volume: 238, article number: 124587

SLU Authors

• Bachour, Raougina

  • Department of Animal Biosciences, Swedish University of Agricultural Sciences
    

• Golovko, Oksana

  • Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences
    

• Pohl, Johannes

  • Department of Animal Biosciences, Swedish University of Agricultural Sciences
    

Sustainable Development Goals

SDG6 Ensure availability and sustainable management of water and sanitation for all
SDG3 Ensure healthy lives and promote well-being for all at all ages


UKÄ Subject classification

Fish and Aquacultural Science
Environmental Sciences


Publication identifier

DOI: https://doi.org/10.1016/j.chemosphere.2019.124587

Permanent link to this page (URI)

https://res.slu.se/id/publ/102235