Scholarlink

<p>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 <i>C.&#xa0;vulgaris</i> from 17.9 to 1.5&#xa0;µM, and for <i>D.&#xa0;tertiolecta</i> from 413.9 to 18.3&#xa0;µM. In contrast, Cr(III) toxicity appeared largely independent of sulfate: the EC50 values ranged for <i>C.&#xa0;vulgaris</i> from 5.0 to 4.0&#xa0;µM, and for <i>D.&#xa0;tertiolecta</i> from 30.8 to 11.5&#xa0;µM. The Cr(VI):SO<sub>4</sub><sup>2−</sup> and Cr(III):SO<sub>4</sub><sup>2−</sup> 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 (<i>C. vulgaris</i>) and 1:200 (<i>D. tertiolecta</i>). 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.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Comparative toxicity of Cr(III) and Cr(VI) to freshwater and marine algae (Chlorella vulgaris, Dunaliella tertiolecta) under varying sulfate concentrations

  • 期刊论文

  • 发表日期：

    2026年2月23日

查看全文
  • Ekaterina Stravinskene,
  • Iurii Grigorev,
  • Nadezhda Artyna

摘要

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. tertiolecta 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.