Reyes et al. (2006) compared the efficiency of
the removal of tetracycline in aqueous suspensions of
TiO2 irradiated with three different light sources: a UV
lamp, natural solar light and a UV-A lamp. No significant
degradation observed when the irradiation was performed
in the absence of TiO2. It was observed 50% degradation
of the drug in the presence of 0.5 g/L of TiO2 in times of
10, 20 and 120 minutes for the UV lamp, natural solar light
and UV-A lamp, respectively. However, all the residues
obtained through the 3 different treatments retained their
bactericidal activity.