Exposure of Mytilus trossulus to diclofenac and 4′-hydroxydiclofenac: Uptake, bioconcentration and mass balance for the evaluation of their environmental fate

• Published in: The Science of the total environment Vol. 791; p. 148172
• Main Authors: Świacka, Klaudia, Smolarz, Katarzyna, Maculewicz, Jakub, Michnowska, Alicja, Caban, Magda
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.10.2021
• Subjects: 4-OH diclofenac; Analgesic; Baltic Sea; bioaccumulation; bioactive properties; Blue mussels; Diclofenac; environment; Environmental fate; metabolites; Mytilus trossulus; NSAIDs; Pharmaceuticals; risk; Analgesic; NSAIDs; Blue mussels; 4-OH diclofenac; Environmental fate; Baltic Sea; Pharmaceuticals; Diclofenac
• ISSN: 0048-9697; 1879-1026; 1879-1026
• DOI: 10.1016/j.scitotenv.2021.148172

Diclofenac (DIC) is one of the most widely consumed drugs in the world, and its presence in the environment as well as potential effects on organisms are the subject of numerous recent scientific works. However, it is becoming clear that the risk posed by pharmaceuticals in the environment needs to be viewed more broadly and their numerous derivatives should also be considered. In fact, already published results confirm that the transformation products of NSAIDs including DIC may cause a variety of potentially negative effects on marine organisms, sometimes showing increased biological activity. To date, however, little is known about bioconcentration of DIC and DIC metabolites and the role of sex in this process. Therefore, the present study for the first time evaluates sex-related differences in DIC bioconcentration and estimates bioconcentration potential of DIC metabolite, 4-OH DIC, in the Mytilus trossulus tissues. In the experiment lasting 7 days, mussels were exposed to DIC and 4-OH DIC at concentrations 68.22 and 20.85 μg/L, respectively. Our study confirms that DIC can be taken up by organisms not only in its native form, but also as a metabolite, and metabolised further. Furthermore, in the present work, mass balance was performed and the stability of both studied compounds under experimental conditions was analysed. Obtained results suggest that DIC is more stable than its derivative under the tested conditions, but further analyses of the environmental fate of these compounds are necessary. [Display omitted] •Diclofenac and 4-hydroxydiclofenac are uptaken from water by M. trossulus.•Diclofenac and 4-hydroxydiclofenac are bioconcentrated in mussel tissues and biofilm.•The bioconcentration of 4-hydroxydiclofenac is significantly different from that of diclofenac.•Diclofenac is metabolised by M. trossulus to 5-hydroxydiclofenac.•5-hydroxydiclofenac was detected only in M. trossulus females.