The purpose of this study was to test the potential role of the aquatic snake Helicops pastazae as an indicator of water pollution caused by heavy metals. In particular, we tested whether the total heavy metal concentration is related to (1) the position (upstream vs downstream) of the sampling point and its distance from the point where wastewater is discharged; (2) the taxonomic group studied: piscivorous snakes vs characid fish that occupy the same habitats; and (3) the organ or tissue examined: snake liver versus muscle. We used atomic absorption spectrophotometry with electrothermal atomization to quantify cadmium (Cd), chromium (Cr) and lead (Pb) and found significant differences between some of the sampling points, with particularly high metal concentrations detected upstream at point 1. However, we found no clear spatial pattern nor any significant differences in the concentration of any of the metals in fish and snake muscle, suggesting that both species accumulate similar amounts of the sampled elements. With regard to interactions, snake liver had the highest concentrations of Cd, while muscle had the highest concentrations of Pb and Cr, which may indicate tissue affinity differences for certain metals. Altogether, our results indicate that H. pastazae accumulates contaminants differentially, depending on the tissue and location, which highlights their potential as bioindicators of water contamination. Further research is necessary to understand their role as bioindicators based on extensive sampling and environmental contaminant data.

本研究的目的是测试水生蛇Helicops Pastazae的潜在作用作为重金属引起的水污染的指标。特别是，我们测试了总重金属浓度是否与（1）采样点的位置（上游与下游）及其与废水排放点的距离有关；(2) 研究的分类群：食鱼蛇与占据相同栖息地的characid鱼；(3) 检查的器官或组织：蛇肝与肌肉。我们使用带有电热雾化的原子吸收分光光度法对镉 (Cd)、铬 (Cr) 和铅 (Pb) 进行量化，发现一些采样点之间存在显着差异，在点 1 上游检测到的金属浓度特别高。然而，我们发现没有清晰的空间模式，鱼和蛇肌肉中任何金属的浓度也没有任何显着差异，表明这两个物种积累了相似数量的采样元素。在相互作用方面，蛇肝的 Cd 浓度最高，而肌肉中 Pb 和 Cr 的浓度最高，这可能表明组织对某些金属的亲和力存在差异。总之，我们的结果表明H. pastazae根据组织和位置不同地积累污染物，这突出了它们作为水污染生物指示物的潜力。需要进一步研究以了解它们作为基于广泛采样和环境污染物数据的生物指示剂的作用。