The degradation of endocrine disruptor di-n-butyl phthalate by UV irradiation: A photolysis and product study

T. K. Lau, Wei Chu, N. Graham

Research output: Journal article publicationJournal articleAcademic researchpeer-review

119 Citations (Scopus)


The direct photolysis of an important endocrine disruptor compound, di-n-butyl phthalate (DBP), has been investigated under monochromatic UV irradiation at 254 nm over a wide pH range (3-11). The investigation was carried out under idealized conditions and has considered both reaction kinetics and the degradation mechanism. It was found that more than 90% of DBP can be degraded within an hour of irradiation in water. A simple model has been developed and used to predict the initial DBP photolysis rate constant at different pH values and initial DBP concentrations. The major decomposition mechanism of DBP is believed to involve the hydrolytic photolysis of the carbon in the α and/or β-position of the ester chain with the production of aromatic carboxylic derivatives. Additionally, multi-degradation pathways are proposed for acid-catalyzed hydrolytic photolysis (pH 3-5), which was found to be useful in explaining the photo-degradation of DBP under acidic conditions. The use of 254 nm UV to photo-degrade DBP was found to be a relatively fast and clean process, especially in neutral to basic conditions.
Original languageEnglish
Pages (from-to)1045-1053
Number of pages9
Issue number8
Publication statusPublished - 1 Aug 2005


  • Di-n-butyl phthalate
  • Endocrine disruptor
  • Photolysis
  • Treatment
  • UV

ASJC Scopus subject areas

  • Chemistry(all)
  • Environmental Chemistry

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