Assessing soil toxicity of the pharmaceutical nimesulide using edaphic fauna Enchytraeus crypticus

With an increase in the generation of sewage sludge, there comes a demand for disposal methods for it, and agricultural use is a sustainable alternative. However, there are gaps regarding emerging pollutants, especially in the pharmaceutical class. Nimesulide - an anti-inflammatory pharmaceutical recently associated with liver damage and banned in some European countries - is among the most consumed pharmaceuticals in Brazil hence can be found in wastewater and, therefore, in sewage sludge used for agriculture at ng L−1 concentrations. The objective of this research was to evaluate the toxicity of the anti-inflammatory pharmaceutical nimesulide through toxicity tests using the organism Enchytraeus crypticus in both natural and artificial soils, adopting concentrations about studies carried out with other anti-inflammatory drugs on seeds in the soil. In this work, the toxicity of nimesulide was evaluated in natural tropical soil sampled in São Paulo – Brazil, and in tropical artificial soil. The invertebrate E. crypticus was exposed to nimesulide nominal concentrations of 200; 340; 578; 982 and 1670 mg nimesulide kg−1 of dry soil and the reproduction test was performed according to ISO 16.387 (2014) standard, with 5 replicates per concentration. The results obtained through reproduction testing with E. crypticus in each concentration presented were EC50 values of 699 and 759 mg nimesulide Kg−1 dry soil, respectively for both natural and artificial soil. The Tukey test showed no significant difference between the soils, however. Finally, this study suggests that the anti-inflammatory drug nimesulide displays a toxicological effect on the reproduction of soil fauna organisms in high concentrations. Therefore, stresses the importance of identifying and monitoring unknown concentrations of this emerging pollutant in the environment. •The organism Enchytraeus crypticus as a bioindicator of pharmaceutical toxicity in soil•There was no significant difference in nimesulide toxicity to E. crypticus in natural and tropical artificial soil.•Reproduction of E. crypticus decreases with increasing anti-inflammatory concentrations.•Low toxicity of nimesulide at high concentrations in artificial soil