Тип публикации: статья из журнала
Адрес в архиве электронных ресурсов СФУ: https://elib.sfu-kras.ru/handle/2311/158169
Аннотация: Sulfate is known to protect microalgae from Cr(VI) toxicity in seawater. We investigated whether varying sulfate levels could lead to a change in the most toxic chromium species for freshwater and marine algae. For Cr(VI), reducing medium sulfate by 125-fold lowered the EC50 for C. vulgaris from 17.9 to 1.5 µM, and for D. tertiolecПоказать полностьюta from 413.9 to 18.3 µM. In contrast, Cr(III) toxicity appeared largely independent of sulfate: the EC50 values ranged for C. vulgaris from 5.0 to 4.0 µM, and for D. tertiolecta from 30.8 to 11.5 µM. The Cr(VI):SO42− and Cr(III):SO42− ratios were calculated to compare the toxicity of the chromium species to the microalgae in terms of dependence on ambient sulfate. Total growth inhibition occurred at Cr(VI):sulfate ratios greater than 1:20 for both algae, while toxicity disappeared below 1:2000 (C. vulgaris) and 1:200 (D. tertiolecta). For Cr(III), both complete and negligible inhibition was observed across a wide range of ratios (1:2000 – 1:20). These findings suggest that seawater sulfate-mediated protection may not be effective against Cr(III). In marine cultures, Cr(III) was more toxic than Cr(VI), contradicting conventional assumptions about the greater toxicity of hexavalent chromium.