Previously there was a risk of selection of antibiotic resistant bacteria in wastewater. However, in the Stockholm County Council sales have been decreasing a lot since 2011, and now the risk of resistance development is considered to be low in the county.
In selection of algae for toxicity testing of antibiotics the European Medicines Agency, EMA, recommends test on blue-green algae (cyanobacteria). No information on toxicity on blue-green algae has been found, which means that a calculation of environmental risk becomes uncertain.
The risk classification insignificant, according to Fass.se, is based on total sold amount (kg) of the substance in Sweden during the year 2014 and the toxicity of the substance.