Quantification of the Sub-lethal Toxicity of Metals and Endocrine-disrupting Chemicals to the Marine Green Microalga Tetraselmis suecica

Abstract

Microalgae are sensitive indicators of environmental changes, and hence they are widely used in environmental risk assessments and for the development of discharge guidelines. Here we evaluated the toxicity of metals and endocrine-disrupting chemicals (EDCs) to the marine green microalga, Tetraselmis suecica. The toxicants investigated included the metals, Cu, Ni, and Pb; and the EDCs, bisphenol A (BPA), endosulfan (ES), and polychlorinated biphenyl (PCB). The endpoints were variations in cell counts and chlorophyll a levels. T. suecica displayed a varied pattern of sensitivity to the toxicants. Based on the 72-h median effective concentration (EC 50 ), ES (0.045 mg/L) was most toxic to T. suecica, followed by PCB (3.96 mg/L) and Pb (9.62 mg/L). Interestingly, T. suecica was relatively tolerant to Cu (43.03 mg/L). The 72-h EC 50 values of Ni and BPA were approximately 16 mg/L. Our data suggest that this species may be relatively tolerant to most of the chemicals within their permissible limits in the environment.

Physiological effects of copper on the freshwater alga Closterium ehrenbergii Meneghini (Conjugatophyceae) and its potential use in toxicity assessments

“…Likewise, exposure of Cu resulted in marked reductions in Chl a concentration in the dinoflagellate Cochlodinium polykrikoides, an effect that was also more pronounced at higher Cu concentrations (Ebenezer et al 2014). Overall, these results clearly demonstrate that the Korean strain of C. ehrenbergii used in this study is considerably more sensitive to Cu than other microalgae that have been tested previously (Cairns et al 1978, Viana and Rocha 2005, Ebenezer and Ki 2013.…”

“…1B). Previous studies have reported that EC 50 for the green algae Chlorella ellipsoidea, Chlorella vulgaris, Chlamydomonas sp., and Tetraselmis suecica were 0.489, 0.200, 8.00, and 43.03 mg L -1 , respectively (Young and Lisk 1972, Cairns et al 1978, Ebenezer and Ki 2013 The cultures were then re-suspended in fresh C medium, and mounted onto a slide and sealed; culture slides were observed with a fluorescence microscope (Carl Zeiss Axioskop, Oberkochen, Germany) to determine the level of ROS production in the cells. ImageJ software (NIH, Bethesda, MD, USA) was used to quantify relative CAF and ROS levels from the fluorescent microscopic images.…”

Development and Application of a Microplate Assay for Toxicity Testing on Aquatic Cyanobacteria

“…has been reported to have a 72-h EC50 of 4.61 mg/L (Yamagishi et al 2016; shake flask test, 23 °C at ~4000 lux), 1 order of magnitude higher than our EC50s, which ranged from 0.66 to 64.5 mg/L. It has been suggested, however, that marine algae are more tolerant to some toxicants, notably metals, than freshwater species (Ebenezer and Ki 2013;Yamagishi et al 2016).…”

Biodegradation and detoxification of bisphenol A by bacteria isolated from desert soils

“…The EC 50 (96 h) of BPA for the freshwater algae (Chlorella pyrenoidosa and Scenedesmus obliquus) were 44.9 mg L −1 and 33.9 mg L −1 , respectively (Li et al 2017). Although previous findings suggest that the marine algae genus Tetraselmis is more tolerant to toxic chemicals than other algae (Ebenezer and Ki 2013), V2 strain seems to be the most sensitive to BPA. This study leads to suggest that our specie may be relatively more efficient in metabolites toxicity assessment due to its high sensitivity.…”