Cytotoxic, Genotoxic, Mutagenic, and Phytotoxic Effects of the Extracts from Eragrostis plana Nees, 1841 (Poaceae), Grown in a Coal-Contaminated Region

Coal and its byproducts and mineral waste constitute complex mixtures, which contain a variety of chemical compounds that impact the ecosystems. For this reason, procedures are required to monitor coal-degraded areas, including the use of biomonitoring organisms. In this light, the aim of the present study was to evaluate the cytotoxicity, genotoxicity, mutagenicity, and phytotoxicity of the aerial part and root extracts from Eragrostis plana Nees collected in the surroundings of the Thermoelectric Power Plant President Médici-UTPM (Candiota, Brazil), through Allium cepa bioassay. Cytotoxicity, genotoxicity, and mutagenicity in the A. cepa meristematic cells were verified through the mitotic index (MI), chromosomal alterations, and micronucleus formation, respectively. In addition, the germination rate, vigor index, and morphological abnormalities were verified in A. cepa seedlings. Treatment with root extracts from E. plana (ACR) specimens collected in a coal-contaminated region resulted in the lowest MI values (8.9%, 12.7%, and 16.0%), representing the most cytotoxic effect when compared with the negative control—NC (dH 2 O) (MI = 35.8%). ACR extract also was the most genotoxic and mutagenic sample compared with NC and other treatments. Phytotoxicity analyses corroborated the toxic action of ACR, presenting abnormal seedlings and change in vigor index. The high concentration of dissolved total chlorides and electrical conductivity presented in the root extracts of E. plana , which were grown in the carboniferous region, indicates an increase in the absorption of metallic ions and organic compound and supports the hypothesis that this species has bioaccumulator potential, being a new biomonitor model of coal-contaminated region.