RECETOX, Faculty of Science, Masaryk University, Kotlarska 2, CZ-62500 Brno, Czech Republic.
RECETOX, Faculty of Science, Masaryk University, Kotlarska 2, CZ-62500 Brno, Czech Republic.
Aquat Toxicol. 2022 Jun;247:106169. doi: 10.1016/j.aquatox.2022.106169. Epub 2022 Apr 10.
Aquatic biotests are important tools targeting various effects in ecotoxicology, including endocrine disruption. Unintentional exposure of bioassay organisms to endocrine disruptors during cultivation or testing may interfere with assessed endpoints. We illustrate this issue on the example of laboratory phytoplankton cultivation, where possible sources of estrogenic compounds have been revealed. Fifty-four blank samples (water and fresh or cultivated growth media) were assessed by in vitro biotests for their estrogenicity, and major known estrogens originating from plastic materials, bisphenol A and alkylphenols, were analyzed in selected samples. The samples of freshly prepared growth medium elicited weak estrogenic response in bioassays and some samples of the aerated media caused responses even above the 50% of maximum of the reference compound (17β-estradiol, E2), while the samples from diverse laboratory water sources did not show significant estrogenic activity. The results identified substances contained in the growth medium as minor but reproducible contributors to estrogenicity in the cultivations. Sporadic but significant effects (up to 4.9 ng E2 equivalent/L) can be ascribed to compounds released from the used plastic materials during aeration of the cultivations. The potential sources of unintentional exposure to estrogenic compounds need to be considered in aquatic cultivations and biotests, since they could impact their outcomes, especially in arrangements assessing reproduction or whole life cycle biotests, or production of bioactive compounds by phytoplankton. The findings emphasize the necessity to assess all relevant blanks, ideally by sensitive high throughput in vitro assays that reflect also unknown pollutants and minimize all potential sources of background contamination. In vitro assays show very good applicability for this purpose since they enable to screen for any background estrogenicity of the used media and materials without the need of analyzing individual compounds, which often might not be known.
水生生物测试是生态毒理学中针对各种效应的重要工具，包括内分泌干扰。在培养或测试过程中，生物测试生物体无意中暴露于内分泌干扰物中可能会干扰评估的终点。我们以实验室浮游植物培养为例说明了这个问题，其中揭示了可能存在雌激素化合物的来源。通过体外生物测试评估了 54 个空白样品（水和新鲜或培养的生长介质）的雌激素活性，并分析了选定样品中源自塑料材料的主要已知雌激素，双酚 A 和烷基酚。新制备的生长培养基样品在生物测定中引起了较弱的雌激素反应，一些充气介质的样品甚至引起了超过参考化合物（17β-雌二醇，E2）的最大响应的 50%，而来自不同实验室水源的样品没有显示出显著的雌激素活性。结果表明，生长培养基中所含物质是培养过程中雌激素的次要但可重复的贡献者。偶尔但显著的效应（高达 4.9 ng E2 当量/L）可归因于培养充气过程中从所用塑料材料中释放的化合物。需要考虑水生培养物和生物测试中无意暴露于雌激素化合物的潜在来源，因为它们可能会影响它们的结果，特别是在评估生殖或整个生命周期生物测试的安排中，或浮游植物产生生物活性化合物的安排中。这些发现强调了评估所有相关空白的必要性，理想情况下通过敏感的高通量体外测定进行评估，这些测定还反映了未知污染物，并最大限度地减少了所有潜在的背景污染来源。体外测定在这方面具有很好的适用性，因为它们能够筛选所用培养基和材料的任何背景雌激素活性，而无需分析通常未知的单个化合物。
