The fates of four aquatic contaminants, namely the 2,4-dichlorophenoxyacetic acid herbicide (2,4-D), the bisphenol A endocrine disruptor (BPA), and the sodium butylnaphthalenesulfonate (BNS) and benzyldodecyldimethylammonium bromide (BDDAB) surfactants by the TiO2-photoassisted ozonation (TiO2/O-3/UV method) were investigated indoors under laboratory conditions (super-high-pressure Hg lamp) and outdoors under natural Sunlight. in laboratory experiments the TiO2/O-3/UV methodology led to significant increases in degradation efficiency relative to ozonation (dark: O-3: or under UV light: O-3/UV) and to the TiO2-photoassisted method of oxygenated dispersions (TiO2/O-2/UV). Mineralizations of the substrates were monitored by total organic carbon (TOC) assays. The BDDAB surfactant, being most recalcitrant to biodegradation and to the TiO2-photoassisted degradation, was mineralized efficiently by the TiO2/O-3/UV method under natural Sunlight at relatively high concentrations of contaminants (1.0 mM) using a tubular-type photoreactor consisting of Pyrex glass tubes and a solar cell system that supplied the needed electrical power. (C) 2009 Elsevier B.V. All rights reserved.