Cytotoxicity, Genotoxicity, and Toxicity of Plant Biostimulants Produced in Brazil: Subsidies for Determining Environmental Risk to Non-Target Species

The great expansion in recent years in the use of plant biostimulants has underestimated the possibility of producing environmental risks. The objective of this study was to evaluate the cytotoxicity, genotoxicity, and toxicity of three different biostimulants (A, B, and C) produced and widely marketed in Brazil and exported to other countries on both plant and animal indicator organisms. In Allium cepa (non-target species of these plant biostimulants), the concentrations evaluated for the products A and B (0.0625 at 0.500 mL/L), and C (0.0625 at 0.500 g/L) induced inhibition of cell proliferation on meristems, in at least one time of analysis, characterizing them as cytotoxic. The three biostimulants promoted an expressive number of prophases in detriment to the other phases of cell division. In the test with Artemia salina, different concentrations of the biostimulants were tested, ranging from 1000 to 1.95 ppm, and the toxic potential was evaluated through the LC50. The three products showed high toxicity (LC50<100 ppm) against microcrustaceans. The results obtained in the present study suggest that the evaluated biostimulants may be toxic to non-target plants and toxic to organisms in water bodies influenced by leaching from soil with the presence of these substances.