The Consequences and Challenges Associated with Amphibian Toxicology Regarding Pesticides

Main Article Content

Andreia Garcês
Isabel Pires


Amphibian populations worldwide are experiencing a decline due to a combination of abiotic and biotic factors. Climate change, habitat loss, pollution, and disease outbreaks all contribute to this decline. Many amphibian species are listed as vulnerable or near extinct (43% of the species described nowadays) on the IUCN Red List. Anthropogenic contaminants, particularly pesticides, can be incredibly harmful to these populations. Pesticides can come from different sources, in particular from agriculture. Contamination of animals can occur through ingestion of contaminated feed, air, drift, secondary poisoning, spillage into local water bodies, contaminated plants and sediments, or groundwater contamination. Higher concentrations of pesticides in the environment can have acute toxic effects with high mortality rates, or long-term exposure can lead to reproductive abnormalities, infertility, and malformations. Several papers have implicated pesticides in the amphibian population decline. The primary objective of the research was to establish a link between the use of pesticides and the decline of amphibian populations, focusing on documented cases in the wild where these chemicals have been identified as the primary cause of mortality among these species and assessing their broader ecological impacts. Additionally, the study aimed to highlight the main challenges encountered in conducting ecotoxicological research on amphibians and to explore potential avenues for future research and mitigation efforts.

Article Details

How to Cite
Garcês, A., & Pires, I. (2023). The Consequences and Challenges Associated with Amphibian Toxicology Regarding Pesticides. Research in Biotechnology and Environmental Science, 2(3), 35–46.
Reveiw Article

Funding data


Quarles W. Protecting amphibians from pesticides. Commom Sense Pest Control. 2015; 29(1-4): 1-19. Available at:

Quaranta A, Bellantuono V, Cassano G, and Lippe C. Why amphibians are more sensitive than mammals to xenobiotics. PLOS ONE. 2009; 4(11): e7699. DOI:

Pessier AP. Amphibia. In: Terio KA, McAloose D, Leger JSt, editors. Pathology of wildlife and zoo animals. Academic Press; 2018. Chapter 38, p. 921-951. DOI:

Sodhi NS, Bickford D, Diesmos AC, Lee TM, Koh LP, Brook BW, et al. Measuring the meltdown: Drivers of global amphibian extinction

and decline. PLOS ONE. 2008; 3(2): e1636. DOI:

The IUCN red list of threatened species. IUCN Red List of Threatened Species. 2022. Available at:

Khan MZ. Effect of agricultural chemicals on reptiles: Comparison of pyrethroid and organophosphate with phytopesticide on cholinesterase activity. Pak J Biol Sci. 2003; 6(9): 821-825. DOI:

Hocking D, and Babbitt K. Amphibian Contributions to Ecosystem Services. Herpetol Conserv Biol. 2014; 9(1): 1-17. Available at:

Kumawat PK, Reena, Hussain T, Jamwal S, Sinha BK, and Yadav PK. Harnessing chemical ecology to address agricultural pest and pollinator: A review. J Entomol Zool Stud. 2021; 9(2): 693-697. Available at:

Nessi A, Cioccarelli S, Tremolada P, Gariano P, Grandinetti M, Balestrieri A, et al. Environmental factors affecting amphibian communities in river basins of the southern apennines. Diversity. 2023; 15(5): 625. DOI:

Bordon K de CF, Cologna CT, Fornari-Baldo EC, Pinheiro-Júnior EL, Cerni FA, Amorim FG, et al. From Animal Poisons and Venoms to Medicines: Achievements, Challenges and Perspectives in Drug Discovery. Front Pharmacol. 2020; 11: 1132. DOI:

Islam A, and Malik MF. Impact of pesticides on amphibians: A review. J Toxicol Ana. 2018; 1(2): 3. Available from:

McCoy KA, and Peralta AL. Pesticides could alter amphibian skin microbiomes and the effects of Batrachochytrium dendrobatidis. Front Microbiol. 2018; 9: 748. DOI:

Berny P. Pesticides and the intoxication of wild animals. J Vet Pharmacol Ther. 2007; 30(2): 93-100. DOI:

Ames BN. Pollution, pesticides, and cancer. J AOAC Int. 1992; 75(1): 1-5. DOI:

Daly GL, Lei YD, Teixeira C, Muir DCG, Castillo LE, and Wania F. Accumulation of current-use pesticides in neotropical montane forests. Environ Sci Technol. 2007; 41(4): 1118-1123. DOI:

Camacho-Rozo CP, Camacho-Reyes JA, Camacho-Rozo CP, and Camacho-Reyes JA. Effect of agricultural pesticides and land use intensification on amphibian larval development. In: Hung SW, Chen CC, Lu CL, Kao TT, Payan-Carreira R, editors. Animal welfare - new insights. Intech Open; 2022. Available at:

Cushman SA. Effects of habitat loss and fragmentation on amphibians: A review and prospectus. Biol Conserv. 2006; 128(2): 231-240. DOI:

White KJ, Petrovan SO, and Mayes WM. Pollutant accumulation in road mitigation tunnels for amphibians: A multisite comparison on an ignored but important issue. Front Ecol Evol. 2023; 11: 1133253. DOI:

Agostini MG, Roesler I, Bonetto C, Ronco AE, and Bilenca D. Pesticides in the real world: The consequences of GMO-based intensive agriculture on native amphibians. Biol Conserv. 2020; 241: 108355. DOI:

Brühl CA, Schmidt T, Pieper S, and Alscher A. Terrestrial pesticide exposure of amphibians: An underestimated cause of global decline?. Sci Rep. 2013; 3(1): 1135. DOI:

Relyea RA. The effects of pesticides, pH, and predatory stress on amphibians under mesocosm conditions. Ecotoxicology. 2006; 15(6): 503-511. DOI:

Slaby S, Marin M, Marchand G, and Lemiere S. Exposures to chemical contaminants: What can we learn from reproduction and development endpoints in the amphibian toxicology literature?. Environ Pollut. 2019; 248: 478-495. DOI:

Center for disease control and prevention (CDC). One Health. 2022. Available at:

24. Baker NJ, Bancroft BA, and Garcia TS. A meta-analysis of the effects of pesticides and fertilizers on survival and growth of amphibians. Sci Total Environ. 2013; 449: 150-156. DOI:

Smyth CW, Sarmiento-Ramírez JM, Short DPG, Diéguez-Uribeondo J, O’Donnell K, and Geiser DM. Unraveling the ecology and epidemiology of an emerging fungal disease, sea turtle egg fusariosis (STEF). PLOS Pathog. 2019; 15(5): e1007682. DOI:

Doyle J, Brinkworth CS, Wegener KL, Carver JA, Llewellyn LE, Olver IN, et al. nNOS inhibition, antimicrobial and anticancer activity of the amphibian skin peptide, citropin 1.1 and synthetic modifications. Eur J Biochem. 2003; 270(6): 1141-1153. DOI:

U.S. Environmental protection agency (EPA). Annual performance report. Data quality records. 2013. Available at:

Burlibasa L. Amphibians as model organisms for study environmental genotoxicity. Appl Ecol Environ Res. 2011; 9: 1-15. DOI:

Environmental risk assessment (ERA). 2023. Available at:

COST Action CA18221 - PEsticide risk assessment for amphibians and reptiles (PERIAMAR). 2023. Available at:

Lushchak VI, Matviishyn TM, Husak VV, Storey JM, and Storey KB. Pesticide toxicity: A mechanistic approach. EXCLI J. 2018; 17: 1101-1136. DOI:

Adams E, Leeb C, Roodt AP, and Brühl CA. Interspecific sensitivity of European amphibians towards two pesticides and comparison to standard test species. Environ Sci Eur. 2021; 33(1): 49. DOI:

Soares MP, Jesus F, Almeida AR, Domingues I, Hayd L, and Soares AMVM. Effects of pH and nitrites on the toxicity of a cypermetrin-based pesticide to shrimps. Chemosphere. 2020; 241: 125089. DOI:

US Geological Survey (USGS) . National water-quality assessment (NAWQA) project. Pesticides in stream sediment and aquatic biota. 2023. Available at:

Pesticides and the Environment. 2023. Available at:

Smalling KL, Reeves R, Muths E, Vandever M, Battaglin WA, Hladik ML, et al. Pesticide concentrations in frog tissue and wetland habitats in a landscape dominated by agriculture. Sci Total Environ. 2015; 502: 80-90. DOI:

Swanson JE, Muths E, Pierce CL, Dinsmore SJ, Vandever MW, Hladik ML, et al. Exploring the amphibian exposome in an agricultural landscape using telemetry and passive sampling. Sci Rep. 2018; 8(1): 10045. DOI:

Sparling DW, and Fellers GM. Toxicity of two insecticides to California, USA, anurans and its relevance to declining amphibian populations. Environ Toxicol Chem. 2009; 28(8): 1696-1703. DOI:

Davidson C, Stanley K, and Simonich SM. Contaminant residues and declines of the Cascades frog (Rana cascadae) in the California Cascades, USA. Environ Toxicol Chem. 2012; 31(8): 1895-1902. DOI:

Sparling DW, Fellers GM, and McConnell LL. Pesticides and amphibian population declines in California, USA. Environ Toxicol Chem. 2001; 20(7): 1591-1595. DOI:

Bradford DF, Knapp RA, Sparling DW, Nash MS, Stanley KA, Tallent-Halsell NG, et al. Pesticide distributions and population declines of California, USA, alpine frogs, Rana muscosa and Rana sierrae. Environ Toxicol Chem. 2011; 30(3): 682-691. DOI:

Brodeur JC, Damonte MJ, Rojas DE, Cristos D, Vargas C, Poliserpi MB, et al. Concentration of current-use pesticides in frogs from the Pampa region and correlation of a mixture toxicity index with

biological effects. Environ Res. 2022; 204: 112354. DOI:

Adams E, Leeb C, and Brühl CA. Pesticide exposure affects reproductive capacity of common toads (Bufo bufo) in a viticultural landscape. Ecotoxicology. 2021; 30(2): 213-223. DOI:

Wolmarans NJ, Bervoets L, Gerber R, Yohannes YB, Nakayama SMM, Ikenaka Y, et al. Bioaccumulation of DDT and other organochlorine pesticides in amphibians from two conservation areas within malaria risk regions of South Africa. Chemosphere. 2021; 274: 129956. DOI:

Hayes TB, Case P, Chui S, Chung D, Haeffele C, Haston K, et al. Pesticide mixtures, endocrine disruption, and amphibian declines: Are we underestimating the impact?. Environmental Health Perspectives. 2006; 114(Suppl 1): 40-50. DOI:

Liston C, and Kagan J. Memory enhancement in early childhood. Nature. 2002; 419: 896. DOI:

Hayes T, Haston K, Tsui M, Hoang A, Haeffele C, Vonk A. Atrazine-induced hermaphroditism at 0.1 ppb in American leopard frogs (Rana pipiens): laboratory and field evidence. Environ Health Perspect. 2003; 111(4): 568-575. DOI:

Lavorato M, Bernabò I, Crescente A, Denoël M, Tripepi S, and Brunelli E. Endosulfan effects on Rana dalmatina tadpoles: Quantitative developmental and behavioral analysis. Arch Environ Contam Toxicol. 2013; 64(2): 253-262. DOI:

Jones DK, Hammond JI, and Relyea RA. Very highly toxic effects of endosulfan across nine species of tadpoles: lag effects and family-level sensitivity. Environ Toxicol Chem. 2009; 28(9): 1939-1945. DOI:

Greulich K, and Pflugmacher S. Differences in susceptibility of various life stages of amphibians to pesticide exposure. Aquat Toxicol. 2003; 65(3): 329-336. DOI:

Hooser EA, Belden JB, Smith LM, and McMurry ST. Acute toxicity of three strobilurin fungicide formulations and their active ingredients to tadpoles. Ecotoxicology. 2012; 21(5): 1458-1564. DOI:

McMahon TA, Halstead NT, Johnson S, Raffel TR, Romansic JM, Crumrine PW, et al. Fungicide-induced declines of freshwater biodiversity modify ecosystem functions and services. Ecol Lett. 2012; 15(7): 714-722. DOI:

Bonmatin JM, Giorio C, Girolami V, Goulson D, Kreutzweiser DP, Krupke C, et al. Environmental fate and exposure; neonicotinoids and fipronil. Environ Sci Pollut Res Int. 2015; 22(1): 35-67. DOI:

Ade CM, Boone MD, and Puglis HJ. Effects of an insecticide and potential predators on green frogs and northern cricket frogs. J Herpetol. 2010; 44(4): 591-600. DOI:

Wagner N, Reichenbecher W, Teichmann H, Tappeser B, and Lötters S. Questions concerning the potential impact of glyphosate-based herbicides on amphibians. Environ Toxicol Chem. 2013; 32(8): 1688-1700. DOI:

Christin MS, Ménard L, Giroux I, Marcogliese DJ, Ruby S, Cyr D, et al. Effects of agricultural pesticides on the health of Rana pipiens frogs sampled from the field. Environ Sci Pollut Res Int. 2013; 20(2): 601-611. DOI:

Mazanti L, Sparling DW, Rice C, Bialek K, Stevenson C, and Teels B. Synergistic effects of a combined exposure to herbicides and an insecticide in Hyla versicolor. Multiple stressor effects in relation to declining amphibian populations. ASTM Special Technical Publication; 2003. p. 111-129. DOI: h10.1520/STP11178S

Hernández AF, Gil F, and Lacasaña M. Toxicological interactions of pesticide mixtures: An update. Arch Toxicol. 2017; 91(10): 3211-3223. DOI:

Meijer M, Hamers T, and Westerink RHS. Acute disturbance of calcium homeostasis in PC12 cells as a novel mechanism of action for (sub) micromolar concentrations of organophosphate insecticides. Neurotoxicology. 2014; 43: 110-116. DOI:

Cedergreen N. Quantifying synergy: A systematic review of mixture toxicity studies within environmental toxicology. PLOS ONE. 2014; 9(5): e96580. DOI:

Sparling D, Linder G, Bishop C, Krest S, editors. Ecotoxicology of Amphibians and Reptiles. 2 ed. CRC Press; 2020.

Relyea RA, and Diecks N. An unforeseen chain of events: Lethal effects of pesticides on frogs at sublethal concentrations. Ecol Appl. 2008; 18(7): 1728-1742. DOI:

Brander SM, Gabler MK, Fowler NL, Connon RE, and Schlenk D. Pyrethroid pesticides as endocrine disruptors: Molecular mechanisms in vertebrates with a focus on fishes. Environ Sci Technol. 2016; 50(17): 8977-8992. DOI:

Fossi MC, and Marsili L. Effects of endocrine disruptors in aquatic mammals. Pure and Applied Chemistry. 2003; 75(11-12): 2235-2247. DOI:

Hayes TB, Khoury V, Narayan A, Nazir M, Park A, Brown T, et al. Atrazine induces complete feminization and chemical castration in male African clawed frogs (Xenopus laevis). Proc Natl Acad Sci. 2010; 107(10): 4612-4617. DOI:

Titran P, Slaby S, Marchand G, Lescuyer A, Lemiere S, and Marin M. Effects of copper on the early development of Xenopus laevis: The case of CuSO4 and Bordeaux mixture solutions. J Xenobiot. 2018; 8(1): 7809. DOI:

Slaby S, Hanotel J, Bodart JF, Lemiere S, Trinel D, Leprêtre A, et al. Biometric Data Assessment on Xenopus Laevis Tadpoles. J Xenobiot. 2016; 6(2): 6587. DOI:

Hanlon SM, and Relyea R. Sublethal effects of pesticides on predator–prey interactions in amphibians. Copeia. 2013; 2013(4): 691-698. DOI:

Sievers M, Hale R, Parris KM, Melvin SD, Lanctôt CM, Swearer SE. Contaminant-induced behavioural changes in amphibians: A meta-analysis. Sci Total Environ. 2019; 693: 133570. DOI:

Denoël M, D’Hooghe B, Ficetola GF, Brasseur C, De Pauw E, Thomé JP, et al. Using sets of behavioral biomarkers to assess short-term effects of pesticide: a study case with endosulfan on frog tadpoles. Ecotoxicology. 2012; 21(4): 1240-1250. DOI:

Sievers M, Hale R, Swearer SE, Parris KM. Contaminant mixtures interact to impair predator-avoidance behaviours and survival in a larval amphibian. Ecotoxicol Environ Saf. 2018; 161: 482-488. DOI:

Gurushankara HP, Krishnamurthy SV, and Vasudev V. effect of malathion on survival, growth, and food consumption of Indian cricket frog (Limnonectus limnocharis) tadpoles. Arch Environ Contam Toxicol. 2007; 52: 251-256. DOI:

Pochini KM, Hoverman JT. Reciprocal effects of pesticides and pathogens on amphibian hosts: The importance of exposure order and timing. Environ Pollut. 2017; 221: 359-366. DOI:

Jones DK, Dang TD, Urbina J, Bendis RJ, Buck JC, Cothran RD, et al. Effect of simultaneous amphibian exposure to pesticides and an emerging fungal pathogen, Batrachochytrium dendrobatidis. Environ Sci Technol. 2017; 51(1): 671-679. DOI:

Buck JC, Hua J, Iii WRB, Dang TD, Urbina J, Bendis RJ, et al. Effects of pesticide mixtures on host-pathogen dynamics of the amphibian chytrid fungus. PLoS One. 2015; 10(7): e0132832. DOI:

Rohr JR, Elskus AA, Shepherd BS, Crowley PH, McCarthy TM, Niedzwiecki JH, et al. Lethal and sublethal effects of atrazine, carbaryl, endosulfan, and octylphenol on the streamside salamander (Ambystoma barbouri). Environ Toxicol Chem. 2003; 22(10): 2385-2392. DOI:

Garcês A, Pires I, and Rodrigues P. Teratological effects of pesticides in vertebrates: a review. J Environ Sci Health, Part B. 2020; 55(1): 75-89. DOI:

Seifer R. Teratology. In: Haith MM, Benson JB, editors. Encyclopedia of infant and early childhood development. San Diego: Academic Press; 2008. p. 333-343. DOI:

Hayes TB, Case P, Chui S, Chung D, Haeffele C, Haston K, et al. Pesticide mixtures, endocrine disruption, and amphibian declines: Are we underestimating the impact?. Environ Health Perspect. 2006; 114(Suppl 1): 40-50. DOI:

Ujházy E, Mach M, Navarová J, Brucknerová I, and Dubovický M. Teratology – past, present and future. Interdiscip Toxicol. 2012; 5(4): 163-168. DOI:

Pawar KR, and Katdare M. Toxic and teratogenic effects of fenitrothion, BHC and carbofuran on embryonic development of the frog Microhyla ornata. Toxicol Lett. 1984; 22(1): 7-13. DOI:

Fenoglio C, Grosso A, Boncompagni E, Gandini C, Milanesi G, Barni S. Exposure to heptachlor: evaluation of the effects on the larval and adult epidermis of Rana kl. esculenta. Aquat Toxicol. 2009 Jan 31;91(2):151–60. DOI:

International Atomic Energy Agency (IAEA). International Atomic Energy Agency. Environmental behaviour of crop protection chemicals Proceedings of an international symposium. 1997. Available at:

Cooke AS. The effects of DDT, dieldrin and 2,4-D on amphibian spawn and tadpoles. Environ Pollut (1970). 1972; 3(1): 51-68. DOI:

Cooke AS. Tadpoles as indicators of harmful levels of pollution in the field. Environ Pollut Series A, Ecol Biolo. 1981; 25(2): 123-133. DOI:

Brooks JA. Otolith abnormalities in Limnodynastes tasmaniensis tadpoles after embryonic exposure to the pesticide dieldrin. Environ Pollut Series A, Ecol Biolo. 1981; 25(1): 19-25. DOI:

Hall RJ, and Swineford D. Toxic effects of endrin and toxaphene on the southern leopard frog Rana sphenocephala. Environ Pollut Series A, Ecol Biolo. 1980; 23(1): 53-65. DOI:

Fordham CL, Tessari JD, Ramsdell HS, and Keefe TJ. Effects of malathion on survival, growth, development, and equilibrium posture of bullfrog tadpoles (Rana catesbeiana). Environ Toxicol Chem. 2001; 20(1): 179-184. DOI:

Snawder JE, and Chambers JE. Toxic and developmental effects of organophosphorus insecticides in embryos of the South African clawed frog. J Environ Sci Health, Part B. 1989; 24(3): 205-218. DOI:

Bacchetta R, Mantecca P, Andrioletti M, Vismara C, and Vailati G. Axial-skeletal defects caused by Carbaryl in Xenopus laevis embryos. Sci Total Environ. 2008; 392(1): 110-118. DOI:

Anderson RJ, and Prahlad KV. The deleterious effects of fungicides and herbicides on Xenopus laevis embryos. Arch Environ Contam Toxicol. 1976; 4(3):312-323. DOI:

Osano O, Oladimeji AA, Kraak MHS, and Admiraal W. Teratogenic effects of amitraz, 2,4-dimethylaniline, and paraquat on developing frog (Xenopus) embryos. Arch Environ Contam Toxicol. 2002; 43(1): 42-49. DOI:

Alvarez R, Honrubia MP, and Herráez MP. Skeletal malformations induced by the insecticides ZZ-Aphox and Folidol during larval development of Rana perezi. Arch Environ Contam Toxicol. 1995; 28(3): 349-356. DOI:

Raj TP, Jebanesan A, Selvanayagam M, and Manohar GJ. Effect of organophosphorus (nuvan) and carbamate (baygon) compounds on Rana hexadactyla (Lesson) with a note on body protein

and liver glycogen. Geobios. 1988. Available at:

Fort DJ, Guiney PD, Weeks JA, Thomas JH, Rogers RL, Noll AM, et al. Effect of Methoxychlor on Various Life Stages of Xenopus laevis. Toxicol Sci. 2004; 81(2): 454-466. DOI:

Cothran RD, Brown JM, and Relyea RA. Proximity to agriculture is correlated with pesticide tolerance: Evidence for the evolution of amphibian resistance to modern pesticides. Evol Appl. 2013; 6(5): 832-841. DOI:

Jones DK, and Relyea RA. Here today, gone tomorrow: Short-term retention of pesticide-induced tolerance in amphibians. Environ Toxicol Chem. 2015; 34(10): 2295-3301. DOI:

Hua J, Morehouse NI, and Relyea R. Pesticide tolerance in amphibians: induced tolerance in susceptible populations, constitutive tolerance in tolerant populations. Evol Appl. 2013; 6(7): 1028-1040. DOI:

Hu GC, Luo XJ, Dai JY, Zhang XL, Wu H, Zhang CL, et al. Brominated flame retardants, polychlorinated biphenyls, and organochlorine pesticides in captive giant panda (Ailuropoda melanoleuca) and red panda (Ailurus fulgens) from China. Environ Sci Technol. 2008; 42(13): 4704-4709. DOI: