Nano-TiO2 at environmentally relevant level facilitated BPA photo-degradation.
BPA degradation was distinctly affected by water chemistry.
More active species were generated in acidic or alkaline than neutral conditions.
Low level of humic acid facilitated BPA degradation by promoting TiO2 dispersion.
High level of humic acid depressed BPA degradation by forming a coat on TiO2 surface.