Assessment of the efficiency of photocatalysis on tetracycline biodegradation

► We evaluated the ability of photocatalysis to improve tetracycline biodegradability. ► By-products were less toxic than tetracycline but were not biodegradable. ► By-product structures elucidated using LC-MS/MS were similar to that of tetracycline. ► In the photocatalytic process, the tetracycline aromatic ring was not opened. ► The main mechanism reaction was an addition of OH on the reactive sites.