Lincomycin solar photodegradation, algal toxicity and removal from wastewaters by means of ozonation

Antibiotic molecules have been reported among the xenobiotics present at trace levels in sewage treatment plant (STP) effluents and aquatic environment. Lincomycin, one of the most used in clinical practices whose presence in the STP effluents has been often documented, is submitted to an extensive investigation to assess its persistence in the environment and toxicity towards different algal strains. The possibility to remove the lincomycin from water by means of ozonation is demonstrated and a reduction of toxicity of ozonated solutions on S. leopoliensis, with respect to untreated solutions containing this compound, is obtained even just for 1 h of treatment. Kinetic constants for the attack to lincomycin of ozone (from 1.53×105 M−1 s−1 at pH=3.0 and 4.93×105 M−1 s−1 at pH=6.7) and OH radicals (4.37×109 M−1 s−1 at pH=5.5 and 4.59×109 M−1 s−1 at pH=7.5) are also evaluated.