Fig. 5. Mineralization of aqueous TNT (0.22 mM) in light-Fenton reactions at pH 7 comparing abiotic with coupled abiotic–biotic treatments at high and low biomass (waste-activated sludge [WAS] or 2,4-dinitrophenol [DNP]) concentrations: (A) WAS biomass; (B) DNP biomass. Abiotic reaction (•); high biomass concentration, either 467 mg WAS L^-1 or 333 mg DNP L^-1 (); low biomass concentration, either 93 mg WAS L^-1 or 67 mg DNP L^-1 (). Abiotic reactions conducted with Fe³⁺ to nitrilotriaceticacid (NTA) ratio = 1:1. Error bars on symbols indicate standard error of means (n = 3, P 0.05); where absent, bars fall within symbols.