Fate of triclosan, triclocarban, and their transformation products in wastewater under nitrifying conditions

•Nitrification wastewater treatment was simulated using laboratory bioreactors.•Greater triclosan reduction occurred at a pH range of 8.5–9.5.•Methyltriclosan was formed under both treatment conditions.•Triclocarban and 2,4-dichlorophenol levels did not change during treatment.