A report of Cylindrospermopsis raciborskii and other cyanobacteria in the water reservoirs of power plants in Ukraine

Abstract

The occurrence of cyanobacteria in freshwaters attracts much attention due to its associated health threats and ecological implications. Yet data on the composition of cyanobacteria taxa and toxigenicity in some regions is still scarce. Here, we explored the occurrence of cyanobacteria and cyanotoxins in three locations in Ukraine (reservoir for Kasperivtsi Hydrothermal Power Plant and outflowing River Seret, and cooling pond of Khmelnytsky Atomic Power Plant) in summer 2017. Cyanobacteria were a dominant fraction at all stations. A number of potent-toxin producers were identified including Cylindrospermopsis raciborskii, Aphanizomenon gracile, Dolichospermum flos-aquae, and Planktothrix agardhii. Screening for the presence of dissolved and particulate content of microcystins (-LR, -YR, and -RR), cylindrospermopsin, and anatoxin-a yielded negative results. The studied waters displayed no toxicity in human platelets in vitro. Further toxicological and ecological studies are necessary to evaluate the potential presence of cyanotoxin producers in Ukraine.

Keywords: Cyanobacteria; Cyanotoxins; Cylindrospermopsis raciborskii; Ukraine.

Fig. 1

Localization of the sampling sites in Western Ukraine. Sites: A (KHPP)—Kasperivtsi water reservoir before dam; B (RS)—River Seret outflowing from Kasperivtsi water reservoir; C (KAPP)—cooling pond of Khmelnytsky Atomic Power Plant

Fig. 2

The abundance of cyanobacteria at three studied sites in August and September 2017

Fig. 3

Cyanobacteria identified at KHPP and RS sites. a Cylindrospermopsis raciborskii, b Aphanizomenon gracile, c Planktothrix agardhii, and d Sphaerospermopsis aphanizomenoides

Fig. 4

The cytotoxicity of filtered water samples in human platelet-rich plasma assessed by means of lactate dehydrogenase leakage assay and compared to that exerted by tert-butyl hydroperoxide (t-BHP; positive control). Asterisk indicates statistically significant difference with control (p < 0.05; Student t test)