Biotoxicity of diclofenac on two larval amphibians: Assessment of development, growth, cardiac function and rhythm, behavior and antioxidant system

• Published in: The Science of the total environment Vol. 683; pp. 624 - 637
• Main Authors: Peltzer, Paola M., Lajmanovich, Rafael C., Martinuzzi, Candela, Attademo, Andrés M., Curi, Lucila M., Sandoval, María T.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15-09-2019
• Subjects: Amphibian; Diclofenac; Ecotoxicology; Emerging contaminant; Emerging contaminant; Ecotoxicology; Amphibian; Diclofenac
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2019.05.275

The non-steroidal anti-inflammatory drug diclofenac (DCF) threatens the health of aquatic animals and ecosystems. In the present study, different biological endpoints (mortality, development and growth, abnormalities, cardiotoxicity, neurotoxicity and antioxidant system) were used to characterize the acute and chronic effects of DCF (at concentrations ranging between 125 and 4000 μg L−1) on two amphibian species from Argentina (Trachycephalus typhonius and Physalaemus albonotatus). Results showed that the larval developmental, growth rates, and body condition of DCF-exposed individuals of both species were significantly reduced. DCF-exposed individuals also showed several morphological abnormalities, including significantly altered body axis, chondrocranium and hyobranchial skeleton, and organ and visceral abnormalities including cardiac hypoplasia, malrotated guts, asymmetrically inverted guts, and cholecystitis. DCF also had a significant effect on the swimming performance of both species: at low concentrations (125 and 250 μg L−1), swimming distance, velocity and global activity decreased, whereas, at high concentrations (1000 and 2000 μg L−1), these behavioral responses increased. Regarding cardiac function and rhythm, at DCF concentrations higher than 1000 μg L−1, the heart frequency and ventricular systole interval of both species were significantly reduced. Regarding the antioxidant system, the activity of acetylcholinesterase indicated that DCF is neurotoxic and thus related to the changes in behavioral performance. The DCF concentrations studied produced a biochemical imbalance between radical oxygen species production and antioxidant systems. The sensitivities to sublethal and chronic DCF exposure in both anuran species were similar, thus indicating the inherent complexity involved in understanding the biotoxic effects of DCF.
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•Chronic exposure to Diclofenac (DCF) affect amphibian larvae.•DCF decrease larval development, growth and body condition.•DCF produced abnormalities in embryos and larvae.•DCF induced cardiotoxic and neurotoxic effects on larvae.•DCF altered larval swimming behaviour and antioxidant system.