Environmental assessment using living test organisms contribute to the timely detection of negative for human health pollutants. Hydra is a small freshwater organism that has been widely used in different types of bioassays to study the toxic potential of numerous chemical substances and is recently growing in popularity for assessing the impacts of water pollutants. Under normal conditions, adult hydra has a radially symmetric body of about 5 mm long with 6–8 straightened tentacles. Hydra is an appropriate bioindicator species because of their simple anatomy, clear morphological reactions in response to alterations in the aquatic environment, high reproduction rate and simplicity of laboratory-scale cultivation. Moreover, in the optimal cultivation environment, hydra reproduces by budding that enables in a short time obtaining a large number of genetically and morphologically identical animals for a bioassay. Here we propose a rapid bioassay for the assessment of the quality of aquatic environment including drinking water, water from natural environments sources and aqueous solutions of chemicals. This bioassay is based on the registration of survival and morphological reactions in hydra (Hydra attenuata), and allows us to determine the acute and chronic toxic effect of water pollutants. We also describe the optimal laboratory-scale cultivation conditions of hydra. Hydra attenuata bioassay of an aqueous medium can be recommended as a State Standard of Ukraine for assessing the quality of natural and drinking waters.

中文翻译：

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Hydra Attenuata，用于确定饮用水和天然水以及化学品水溶液的急性致死和慢性毒性的模型系统

使用活的测试生物进行环境评估有助于及时发现对人体健康有害的污染物。Hydra是一种小型淡水生物，已广泛用于不同类型的生物测定中，以研究多种化学物质的潜在毒性，并且最近在评估水污染物影响方面越来越流行。在正常情况下，成人九头蛇有一个径向对称的身体，长约5毫米，有6-8个伸直的触手。九头蛇是一种合适的生物指示剂，因为它们的简单解剖结构，对水生环境变化的清晰形态反应，高繁殖率和实验室规模化养殖的简便性。而且，在最佳栽培环境下 hydra通过出芽繁殖，可以在短时间内获得大量遗传上和形态上相同的动物用于生物测定。在这里，我们提出了一种快速生物测定法，用于评估水环境质量，包括饮用水，自然环境来源的水和化学品的水溶液。此生物测定法是基于hydra中存活和形态反应的记录（Hydra sorba），使我们能够确定水污染物的急性和慢性毒性作用。我们还描述了九头蛇的最佳实验室规模培养条件。可以推荐使用水性介质的九头蛇生物测定作为乌克兰的国家标准，以评估天然和饮用水的质量。