RECETOX, Faculty of Science, Masaryk University, Kotlarska 2, Brno, Czech Republic.
Department of Botany, Faculty of Science, University of South Bohemia, Na Zlaté stoce 1, České Budějovice, Czech Republic.
Chemosphere. 2023 Nov;341:140015. doi: 10.1016/j.chemosphere.2023.140015. Epub 2023 Aug 30.
Some freshwater phytoplankton species have been suggested to produce estrogenic compounds in concentrations which could cause adverse effects to aquatic biota, while other studies showed no estrogenic effects after exposure to phytoplankton extracts or pointed out possible sources of the overestimation of the estrogenic activity. This study aimed to clarify these research inconsistencies by investigating estrogenicity of biomass extracts from both environmental freshwater blooms and laboratory cyanobacterial and algae cultures by in vitro reporter bioassay. Biomasses of 8 cyanobacterial and 3 algal species from 7 taxonomic orders were extracted and tested. Next to this, samples of environmental water blooms collected from 8 independent water bodies dominated by phytoplankton species previously assessed as laboratory cultures were tested. The results showed undetectable or low estrogenicity of both freshwater blooms and laboratory cultures with E2 equivalent concentration (EEQ) in a range from LOQ up to 4.5 ng EEQ/g of dry mass. Moreover, the co-exposure of biomass extracts with environmentally relevant concentration of model estrogen (steroid hormone 17β-estradiol; E2), commonly occurring in surface waters, showed simple additive interaction. However, some of the biomass extracts elicited partially anti-estrogenic effects in co-exposure with higher E2 concentration. In conclusion, our study documents undetectable or relatively low estrogenic potential of biomass extracts from both environmental freshwater blooms and studied laboratory cultured cyanobacterial and algae species. Nevertheless, in case of very high-density water blooms, even this low estrogenicity (detected for two cyanobacterial species) could lead to EEQ content in biomass reaching effect-based trigger values indicating potential risk, if recalculated per water volume at field sites. However, these levels would not occur in water under realistic environmental scenarios and the potential estrogenic effects would be most probably minor compared to other toxic effects caused by massive freshwater blooms of such high densities.
一些淡水浮游植物物种被认为会产生浓度足以对水生生物群产生不利影响的雌激素化合物，而其他研究则表明在暴露于浮游植物提取物后没有雌激素作用，或者指出了高估雌激素活性的可能来源。本研究旨在通过体外报告生物测定法研究环境淡水水华和实验室蓝藻和藻类培养物的生物量提取物的雌激素活性，以澄清这些研究中的不一致之处。从 7 个分类目中提取并测试了 8 种蓝藻和 3 种藻类的生物量。除此之外，还测试了从 8 个独立水体中采集的环境水华样本，这些水体以前被评估为蓝藻实验室培养物。结果表明，无论是淡水水华还是实验室培养物的生物量提取物均表现出不可检测或低雌激素活性，其 E2 当量浓度（EEQ）范围从 LOQ 到 4.5ng EEQ/g 干质量。此外，在环境相关浓度的模型雌激素（甾体激素 17β-雌二醇；E2）与生物量提取物的共暴露中，表现出简单的相加相互作用。然而，一些生物量提取物在与较高 E2 浓度共暴露时表现出部分抗雌激素作用。总之，我们的研究表明，从环境淡水水华和研究的实验室培养的蓝藻和藻类物种的生物量提取物中均未检测到或仅具有相对较低的雌激素潜力。然而，在高密度水华的情况下，即使是这种低雌激素活性（在两种蓝藻中检测到）也可能导致生物量中的 EEQ 含量达到基于效应的触发值，表明存在潜在风险，如果在现场按水体体积重新计算，则会出现这种情况。然而，在实际的环境情况下不会出现这些水平，并且与如此高密度的淡水水华引起的其他毒性影响相比，潜在的雌激素效应很可能较小。
