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The harmful effect of ionic liquids (ILs) on the environment is one of the important elements of scientific research conducted around the world. This study presents the effect of ionic liquids, containing the asymmetric cations benzyltrimethylammonium chloride [BenzTMA][Cl] and benzyltriethylammonium chloride [BenzTEA][Cl], on physiological and biochemical changes in common radish plants and spring barley seedlings. The examined ILs demonstrated low toxicity to higher plants. The compound that exhibited higher phytotoxicity to these plant species was [BenzTMA][Cl], whereas the plant that was more resistant to such ILs was common radish. Both the ionic liquids, particularly at higher concentrations, led to changes in the metabolism of plants, which resulted in a decrease of chlorophyll a, chlorophyll b, total chlorophyll, and carotenoids content. The observed changes were positively correlated with increasing concentrations of the examined ILs in the soil. In the case of spring barley, a decrease in the fresh weight and an increase in the dry weight of the seedlings were also observed. The evidence of oxidative stress occurrence in spring barley was observed due to the accumulation of malondialdehyde and free proline, as well as due to an increase in the activity of catalase and peroxidase. The changes in these biomarkers indicating oxidative stress occurrence in common radish plants were much lower. An increase in the content of chloride ions was observed in both the plants.

This paper assesses the impact of sodium fluoride on the morphological parameters and activity of catalase and peroxidase during the germination and root growth phases of three winter wheat cultivars: Tobak, Dalewar, and Arkadia. During examination, the seeds were placed on plastic Petri dishes with an NaF solution at concentrations of 0 (control), 2.5, 5.0, 8.0, and 10.0 mmol dm−3. The obtained results have shown a decrease in germination, inhibition of root growth, and inhibition of catalase activity, both in the embryos and roots of all tested winter wheat cultivars. The observed effects have been strengthened with the increase of the fluoride concentration. However, the effect of NaF on the peroxidase activity has been dependent on the wheat cultivar. It is difficult to state unequivocally which of the tested winter wheat cultivars has been characterized by the highest sensitivity to fluoride. An η2 analysis has confirmed that the NaF concentration has a greater effect than the winter wheat cultivar on the activity of the determined antioxidant enzymes.

Due to their numerous useful properties, quaternary ammonium salts (QAS), including ionic liquids, are increasingly 2017). Considering the chemical structure, these substances are included in the ionic compounds containing four organic groups per molecule, bound with nitrogen atoms (three covalent and one dipolar bond) (Pernak, 2013). According to the literature data, the annual QAS production exceeds the amount of 1 million tons, and the These substances are typically used at low concentrations; thus, the production level proves their immense economof quaternary ammonium salts results in high possibility of their penetration to the environment, directly or indirectly with domestic and industrial sewage or rain water (Biczak et al., 2016). Soil is a living, dynamic ecosystem, and the fate of chemical substances including newly synthesized quaternary ammonium salts must be constantly monitored.

This paper assesses the dissipation of napropamide and its impact on the activity of dehydrogenases, alkaline phosphatase, acid phosphatase, and urease in sandy clay loam. The experiment was carried out on soil samples with organic carbon content of 12.08 g·kg -1 , total nitrogen content of 0.97 g·kg -1 , and pH 5.24 with the following variable factors: (a) dose of Devrinol 450 SC formation (containing 450 g of napropamide in dm 3 ): 0 (control), 0.5, 1, 2, 4, 8, and 16-fold hold of field dose; (b) day of experiment: 1, 7, 14, 28, 56, and 112. The half-life of napropamide ranged from 33.50 to 71.42 days. The use of napropamide at the dose recommended by the manufacturer and at the dose reduced by half appeared to exhibit low toxicity in relation to enzymes determined. In contrast, the application of elevated napropamide doses decreased the values of biochemical parameters of the soil in most cases. The Pearson's correlation coefficients showed statistically significant negative correlation between the content of napropamide residues and the enzymatic activity of the soil.