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- Evaluation of parental and transgenerational effects of clotrimazole in Daphnia magna — A multi-parametric approachPublication . Ferreira, David; Alkimin, G. D.; Neves, Bruna; Conde, Tiago; Domingues, M. Rosário; Nunes, BrunoAzole antifungals inhibit the cytochrome P450 complex, decreasing the production of ergosterol in fungi, and compromising the biosynthesis of ecdysteroids in crustaceans, which are hormones regulating reproduction and ecdy-sis. The azole antifungal clotrimazole (CLO) raises environmental concerns due its toxicity. This work evaluated the effects on the number of moults, feeding rate, growth, reproduction, transgenerational reproductive effects on two dif-ferent generations (F0, parental generation; and F1, organisms born from F0), and energetic balance in Daphnia magna. Neonates (<24 h) were exposed to sublethal concentrations (0, 2.7, and 3.4 mg/L) of CLO, to assess its effects on the moulting process. Neonates were also exposed to environmentally realistic concentrations of CLO (0, 30,150, 750, and 3750 ng/L) for 24 and 96 h, to assess adverse effects on their feeding behaviour. Effects on energy reserves (fatty acids, glycogen, and protein levels) were also measured in animals exposed to CLO. A reproduction test was carried out to evaluate the amount and size of neonates from F0 and F1 generations. CLO exposure decreased the number of moults, and the size of organisms, but did not alter the feeding pattern of 5 days old individuals. However, neonates (<24 h) exposed to CLO had a significant decrease in their feeding pattern. CLO decreased the fatty acids content in exposed animals, but did not change glycogen and protein. CLO also decreased the size of adult daphnids from the third brood, born from animals exposed in F0; in F1 animals, the size of neonates from the third brood was decreased. This study evidenced the toxic effects caused by CLO on growth, feeding and reproduction of D. magna. Nevertheless, it is not pos-sible to conclude whether the effects are due to the inhibition of cytochrome P450 enzymes, or to unspecific effects caused by general toxic stress and decreased nutrition.
- Looking beyond the obvious: the ecotoxicological impact of the leachate from fishing nets and cables in the marine mussel Mytilus galloprovincialisPublication . Vilke, Juliano Marcelo; GARCIA DA FONSECA, TAINÁ; Dias de Alkimin, Gilberto; Ribeiro Gonçalves, Joanna Melissa; Edo Cuesta, Carlos; d’ Errico, Giuseppe; Seilitz, Fredric Södergren; Rotander, Anna; Benedetti, Maura; Regoli, Francesco; Lüchmann, Karim H.; Bebianno, MariaOnce in the marine environment, fishing nets and cables undergo weathering, breaking down into micro and nano -size particles and leaching plastic additives, which negatively affect marine biota. This study aims to unravel the ecotoxicological impact of different concentrations of leachate obtained from abandoned or lost fishing nets and cables in the mussel Mytilus galloprovincialis under long-term exposure (28 days). Biochemical biomarkers linked to antioxidant defense system, xenobiotic biotransformation, oxidative damage, genotoxicity, and neurotoxicity were evaluated in different mussel tissues. The chemical nature of the fishing nets and cables and the chemical composition of the leachate were assessed and metals, plasticizers, UV stabilizers, flame retardants, antioxidants, dyes, flavoring agents, preservatives, intermediates and photo initiators were detected. The leachate severely affected the antioxidant and biotransformation systems in mussels' tissues. Following exposure to 1 mg center dot L -1 of leachate, mussels' defense system was enhanced to prevent oxidative damage. In contrast, in mussels exposed to 10 and 100 mg center dot L -1 of leachate, defenses failed to overcome pro -oxidant molecules, resulting in genotoxicity and oxidative damage. Principal component analysis (PCA) and Weight of Evidence (WOE) evaluation confirmed that mussels were significantly affected by the leachate being the hazard of the leachate concentrations of 10 mg center dot L -1 ranked as major, while 1 and 100 mg center dot L -1 was moderate. These results highlighted that the leachate from fishing nets and cables can be a threat to the heath of the mussel M. galloprovincialis .