One of the direct causes of biodiversity loss is environmental pollution resulting from the use of chemicals. Different kinds of chemicals, such as persistent organic pollutants and some heavy metals, can be endocrine disruptors, which act at low doses over a long period of time and have a negative effect on the reproductive and thyroid system in vertebrates worldwide. Research on the effects of endocrine disruptors and the use of bioindicators in neotropical ecosystems where pressure on biodiversity is high is scarce. In Chile, although endocrine disruptors have been detected at different concentrations in the environments of some ecosystems, few studies have been performed on their biological effects in the field. In this work, Xenopus laevis (African clawed frog), an introduced species, is used as a bioindicator for the presence of endocrine disruptors in aquatic systems with different degrees of contamination in a Mediterranean zone in central Chile. For the first time for Chile, alterations are described that can be linked to exposure to endocrine disruptors, such as vitellogenin induction, decreased testosterone in male frogs, and histological changes in gonads. Dioxin-like and oestrogenic activity was detected in sediments at locations where it seem to be related to alterations found in the frogs. In addition, an analysis of land use/cover use revealed that urban soil was the best model to explain the variations in frog health indicators. This study points to the usefulness of an invasive species as a bioindicator for the presence of endocrine-disruptive chemicals.

中文翻译：

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非洲爪蟾是智利中部地区内分泌干扰物的生物指示剂。

生物多样性丧失的直接原因之一是使用化学品造成的环境污染。各种化学物质，例如持久性有机污染物和某些重金属，可能是内分泌干扰物，它们长时间低剂量起作用，并对全世界脊椎动物的生殖和甲状腺系统产生负面影响。缺乏对生物多样性压力高的新热带生态系统内分泌干扰物的影响和生物指示剂的使用的研究。在智利，尽管在某些生态系统的环境中发现了浓度不同的内分泌干扰物，但对其田间生物学效应的研究很少。在这项工作中，非洲爪蟾（Xenopus laevis）是一种引种，在智利中部的地中海区域，作为污染程度不同的水生系统中存在内分泌干扰物的生物指示剂。智利首次描述了与内分泌干扰物暴露相关的改变，例如卵黄蛋白原诱导，雄蛙睾丸激素降低和性腺组织学改变。在与蛙类中发现的变化有关的沉积物中发现了类似二恶英和雌激素的活性。此外，对土地利用/覆盖物利用的分析表明，城市土壤是解释青蛙健康指标变化的最佳模型。这项研究指出了入侵物种作为存在内分泌干扰性化学物质的生物指示剂的有用性。