Exposure to the antifouling chemical medetomidine slows development, reduces body mass, and delays metamorphosis in wood frog (Lithobates sylvaticus) tadpoles
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Antifouling chemicals have a long history of causing toxicity to aquatic organisms. We measured growth and developmental timing in wood frog tadpoles exposed to the antifouling chemical medetomidine (10 nM–10 μM) starting at two different developmental stages in static renewal experiments. For tadpoles hatched from egg masses and exposed for 3 weeks to 100 nM and 1 μM, head width/total body length ratio was significantly shorter compared to control. For field-collected tadpoles at Gosner stage 24–25 and exposed for 2 weeks, 1 and 10 μM medetomidine significantly slowed development as measured by Gosner stage. Medetomidine (1 and 10 μM) significantly increased the time to metamorphosis by over 16 days on average, and at 100 nM and 1 μM, it significantly decreased mass at metamorphosis. We discuss the possible effects of antifouling chemicals containing medetomidine on globally threatened groups such as amphibians.
KeywordsEcotoxicology Amphibians Medetomidine Tadpole Metamorphosis Aquatic
We thank K. Hiraizumi for statistical advice and two anonymous reviewers for helpful comments.
This work was supported in part by a grant to Gettysburg College from the Howard Hughes Medical Institute through the Precollege and Undergraduate Science Education Program.
Compliance with ethical standards
The collection and use of all animals was approved by the Institutional Animal Care and Use Committee (IACUC) of Gettysburg College.
- Ahren B (1985) Effects of alpha-adrenoceptor agonists and antagonists on thyroid hormone secretion. Acta Endocrinol 108(2):184–191Google Scholar
- Berven KA (1982) The genetic basis of altitudinal variation in wood frog Rana sylvatica. I An experimental analysis of life history traits. Evolution 36(5):962–983. https://doi.org/10.1111/j.1558-5646.1982.tb05466.x Google Scholar
- Bruhl CA, Schmidt T, Pieper S, Alscher A (2013) Terrestrial pesticide exposure of amphibians: an underestimated cause of global decline? Sci Rep 3(1). https://doi.org/10.1038/srep01113
- Conners DE, Rogers ED, Armbrust KL, Kwon JW, Black MC (2009) Growth and development of tadpoles (Xenopus laevis) exposed to selective serotonin reuptake inhibitors fluoxetine and sertraline, throughout metamorphosis. Environ Toxicol Chem 28(12):2671–2676. https://doi.org/10.1897/08-493.1 CrossRefGoogle Scholar
- European Chemicals Agency (2008) CLH report for medetomidine, proposal for harmonised classification and labeling, UK Competent Authority. Available from: https://echa.europa.eu/documents/10162/13626/clh_proposal_medetomidine_en.pdf
- Floyd RH, Wade J, Crain DA (2008) Differential acute sensitivity of wild Rana sylvatica and laboratory Xenopus laevis tadpoles to the herbicide atrazine. Bios 79(3):115–119.Google Scholar
- Fong PP, Thompson LB, Carfagno GLF, Sitton AJ (2016) Long-term exposure to gold nanoparticles accelerates larval metamorphosis without affecting mass in wood frogs (Lithobates sylvaticus) at environmentally relevant concentrations. Environ Toxicol Chem 35(9):2304–2310. https://doi.org/10.1002/etc.3396 CrossRefGoogle Scholar
- Gosner KL (1960) A simplified table for staging anuran embryos and larvae with notes on identification. Herpetologica 16(3):183–190Google Scholar
- LaFortune M, Mitchell MA, Smith JA (2001) Evaluation of medetomidine, clove oil and propofol for anesthesia of leopard frogs, Rana pipiens. J Herp Med Surg 11(4):13–18Google Scholar
- Lefcort H, Thomson SM, Cowles EE, Harowicz HL, Livaudais BM, Roberts WE, Ettinger WF (1999) Ramifications of predator avoidance: predator and heavy metal-mediated competition between tadpoles and snails. Ecol Appl 9(4):1477–1489.Google Scholar
- Lennquist A, Asker N, Kristiansson E, Brenthel A, Bjornsson BT, Kling P, Hultman M, Larsson DG, Forlin L (2011) Physiology and mRNA expression in rainbow trout (Oncorhynchus mykiss) after long-term exposure to the new antifoulant medetomidine. Comp Biochem Physiol C 154(3):234–241Google Scholar
- Lind U, Rosenblad MA, Frank LH, Falkbring S, Brive L, Laurila JM, Pohjanoksa K, Vuorenpas A, Kukkonen JP, Gunnarsson L, Scheinin M, Lindblad LGEM, Blomberg A (2010) Octopamine receptors from the barnacle Balanus improvisus are activated by the alpha2-adrenoceptor agonist medetomidine. Mol Pharmacol 78:237–248CrossRefGoogle Scholar
- Mohammed A (2013) Why are early life stages of aquatic organisms more sensitive to toxicants than adults? In: Gowder S (ed) New insights into toxicity and drug testing. InTech Publishing, pp 49–62. https://doi.org/10.5772/55187
- Ohlauson C, Eriksson KM, Blanck H (2012) Short-term effects of medetomidine on photosynthesis and protein synthesis in periphyton, epipsammon and plankton communities in relation to predicted environmental concentrations. Biofouling 28(5):491–499. https://doi.org/10.1080/08927014.2012.687048 CrossRefGoogle Scholar
- Thompson LB, Carfagno GLF, Andresen K, Sitton AJ, Bury T, Lee LL, Lerner KT, Fong PP (2017) Differential uptake of gold nanoparticles by two species of tadpole, the wood frog (Lithobates sylvaticus) and the bullfrog (L. catesbeianus). Env Tox Chem 36(12):3351–3358. https://doi.org/10.1002/etc.3909 CrossRefGoogle Scholar