Effects of the Antibiotic Amoxicillin on Key Species of the Terrestrial Environment

The antibiotic amoxicillin (AMX) is globally important for human and animal health. Although AMX is considered as a threat for the aquatic and terrestrial environment, limited data are present for its toxicity against key species such as denitrifying bacteria in soil, earthworms and plants. In the present research, the OECD protocols for environmental risk assessment were applied to study AMX acute toxicity, at nominal concentrations, close to the environmentally relevant, in soil bacteria responsible for nitrogen cycling, in the earthworm species Eisenia fetida and six plant species. The results revealed no significant effects of the antibiotic on the parameters related to the end-points of each respective test, at the selected concentration range. Therefore, the antibiotic did not present acute toxicity for the species, under the framework of the OECD tests. Further research is essential to be conducted also considering the patterns of degradation of AMX during the experimental periods.