Department of Earth and Environmental Sciences, University of Pavia, I-27100, Pavia, Italy.
Department of Environmental Science and Policy, University of Milan, I-20133, Via Celoria, 26, Milan, Italy.
Environ Sci Pollut Res Int. 2023 Jan;30(5):13688-13696. doi: 10.1007/s11356-022-23131-4. Epub 2022 Sep 22.
Microplastics (MPs) are nowadays abundant, persistent, and ubiquitous in the environment, representing a new threat for terrestrial, marine, and freshwater ecosystems. Although anuran populations and species are globally declining, the effect of MP exposure on this taxon has been poorly investigated. With the aim of assessing the effects of microplastic exposure on the defensive responses of Italian agile frog (Rana latastei) tadpoles, we exposed them to three different concentrations (1, 7, and 50 mg L) of a mixture of plastic polymers (HPDE, PVC, PS, and PES) for 2 weeks. Then, we measured the total distance covered by individual tadpoles before and after exposure to tadpole-fed dragonfly larvae (Aeshna cyanea) cues. As expected, predation risk sharply lowered the total distance travelled by tadpoles; however, MP concentration did not affect their defensive performances. We also collected data on tadpole development, activity, and mortality. In contrast with previous experiments, neither tadpole growth nor mortality varied with MP concentration. Our results indicate that the intensity of MP effects on growth and development may depend on tadpole size, with large tadpoles being less susceptible to the negative effects of MP exposure.
微塑料（MPs）在当今环境中大量存在、持久且无处不在，对陆地、海洋和淡水生态系统构成了新的威胁。尽管全球范围内的蛙类种群和物种数量正在减少，但对这一类群的 MPs 暴露的影响研究甚少。为了评估微塑料暴露对意大利敏捷蛙（Rana latastei）蝌蚪防御反应的影响，我们将它们暴露于三种不同浓度（1、7 和 50 mg/L）的塑料聚合物混合物（HPDE、PVC、PS 和 PES）中 2 周。然后，我们测量了个体蝌蚪在暴露于蝌蚪喂养的蜻蜓幼虫（Aeshna cyanea）提示前后所覆盖的总距离。正如预期的那样，捕食风险急剧降低了蝌蚪的总行进距离；然而，MP 浓度并未影响它们的防御表现。我们还收集了关于蝌蚪发育、活动和死亡率的数据。与之前的实验相反，MP 浓度既不会影响蝌蚪的生长，也不会影响死亡率。我们的结果表明，MP 对生长和发育的影响强度可能取决于蝌蚪的大小，较大的蝌蚪对 MP 暴露的负面影响的敏感性较低。
