Toxic effects of chlorpyrifos, cypermethrin and glyphosate on the non-target organism Selenastrum capricornutum (Chlorophyta)

Abstract

The toxic effects of the insecticides chlorpyrifos and cypermethrin, and the herbicide glyphosate on the growth, biovolume and ultrastructure of the green microalgae Selenastrum capricornutum were evaluated. Concentrations between 9.37-150 mg L -1 of chlorpyrifos, 3.12-100 mg L -1 of cypermethrin and 4.7-60 mg L -1 of glyphosate were assayed along with a control culture. The assayed concentrations were prepared using commercial formulations. After 48 h all tested concentrations of the three pesticides reduced signifi cantly the population growth. The 96 h effective concentration 50 (EC 50 ) was 14.45 mg L -1 for chlorpyrifos, 12.37 mg L -1 for cypermethrin and 15.60 mg L -1 for glyphosate. Cells exposed to the three pesticides showed an increase in the cellular size related to the increase in pesticide concentration and exposure time. The most significant damages observed on the ultrastructure of cells exposed to the three pesticides included thylakoids and mitochondria disruption, formation of electrodense bodies, accumulation of lipids and increase in the size and number of starch granules.The present study demonstrates that the effects of pesticides also extend to non-target organisms having signifi cant ecological implications.

Hormesis, the Individual and Combined Phytotoxicity of the Components of Glyphosate-Based Formulations on Algal Growth and Photosynthetic Activity

“…The toxicity of GBHs on algae species was investigated in several studies [ 115 , 116 , 117 ]. The toxicity values determined for Roundup Classic (corrected with glyphosate content) on P. subcapitata (72 h EC 50 values: 5.1 ± 1.3 mg/L) correlated well with some of the published 72 h EC 50 values (0.7–5.8 mg/L) for Roundup formulations [ 15 , 73 , 118 ]; however, they remain well below the values published in other studies (15.6–64.7 mg/L) [ 52 , 119 ]. In contrast to the 72 h EC 50 values demonstrated on the MSDS of the tested formulations for algal test organisms (72 h EC 50 values = 2.1 mg/L ( P. subcapitata , Roundup Classic) and 140 mg/L ( D. subspicatus , Medallon Premium) [ 97 , 98 ]), our toxicity values were significantly higher.…”

“…The toxic effects of glyphosate and its formulations have been studied in numerous aquatic organisms, such as various algae species [ 51 , 52 ], crustaceans (e.g., Daphnia magna ) [ 53 ], mollusks [ 54 ], fish [ 55 ], and amphibians [ 56 ]. Based on the results of ecotoxicological testing performed on a wide range of aquatic plant and animal organisms, the damage to different physiological and behavioral functions was demonstrated [ 20 ].…”

“…In addition, altered cell morphology, disrupted ultrastructure (e.g., damaged thylakoids and mitochondria) as well as altered biochemical and physiological parameters (e.g., antioxidant activity, lipid peroxidation) were also demonstrated in algae [ 52 , 68 , 69 ]. Additionally, differences were observed in the sensitivity of the investigated aquatic organisms, even with similar lifestyles, habitats, or identical taxa [ 70 , 71 , 72 ].…”

Pesticide responses of Arctic and temperate microalgae differ in relation to ecophysiological characteristics

“…In comparison, this impact on electron transport was accompanied by a weaker ability to dissipate excess energy (Dio/RC) in the Arctic diatom, resulting in its greater sensitivity to chlorpyrifos. In addition, some authors have suggested that insecticides disturb the cell cycle of Selenastrum capricornutum since they observed the inhibition of cell-separation, resulting in the intracellular accumulation of macromolecules, which are responsible for increasing the biovolume in A-CN (Fernandez et al 2021, Rioboo et al 2002.…”

Combined Effect of Pesticides Containing Active Ingredients of Chlorpyrifos and Mancozeb on the DNA Damage of Chlorella Sorokiniana Shihira and Krauss

“…Previous studies have been done on the toxicity of pesticides to evaluate the effects of chlorpyrifos individually on growth, chlorophyll contents, enzyme activities (Chen et al, 2016;Bhuvaneswari et al, 2018), and microalgal cell ultrastructure (Asselborn et al, 2015;Fernández et al, 2021). Meanwhile, mancozeb induces DNA damage and necrosis in HepG2 and A549 cell lines (Lori et al, 2021).…”