Journal
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
Volume 25, Issue 14, Pages 13489-13498Publisher
SPRINGER HEIDELBERG
DOI: 10.1007/s11356-018-1470-z
Keywords
Ranitidine; NDMA; Ozonation; Chloramination
Categories
Funding
- National Natural Science Foundation of China [51508209, 51678255]
- 1st class General Financial Grant from China Post-Doctoral Funding [2015M580561]
- Special Financial Grant from China Post-Doctoral Funding [2016T90595]
- Natural Science Foundation of Fujian province [2015J05102]
- Scientific Research project for Young teachers - Education Department of Fujian Province [JA15033]
- Science Research Foundation of Huaqiao University [15BS105]
- Promotion Program for Young and Middle-aged Teacher in Science and Technology Research of Huaqiao University [ZQN-PY413]
Ask authors/readers for more resources
Formation oftoxic N-nitrosodimethylamine (NDMA) by chloramination of ranitidine, a drug to block histamine, was still an ongoing issue and posed a risk to human health. In this study, the effect of ozonation prior to chloramination on NDMA formation and the transformation pathway were determined. Influencing factors, including ozone dosages, pH, hydroxyl radical scavenger, bromide, and NOM, were studied. The results demonstrated that small ozone dosage (0.5 mg/L) could effectively control NDMA formation from subsequent chloramination (from 40 to 0.8%). The NDMA molar conversion was not only influenced by pH but also by ozone dosages at various pre-ozonation pH (reached the highest value of 5% at pH 8 with 0.5 mg/LO3 but decreased with the increasing pH with 1 mg/LO3). The N DMA molar yield by chloramination of ranitidine without pre-ozonation was reduced by the presence of bromide ion due to the decomposition of disinfectant. However, due to the formation of brominated intermediate substances (i.e., dimethylamine (DMA), dimethyl-aminomethyl furfuryl alcohol (DFUR)) with higher NDMA molar yield than their parent substances, more NDMA was formed than that without bromide ion upon ozonation. Natural organic matter (NOM) and hydroxyl radical scavenger (tert-butyl alcohol, tBA) enhanced NDMA generation because of the competition of ozone and more ranitidine left. The NDMA reduction mechanism by pre-ozonation during chloramination of ranitidine may be due to the production of oxidation products with less NDMA yield (such as DMA) than parent compound. Based on the result of Q-TOF and GC-MS/MS analysis, three possible transformation pathways were proposed. Different influences of oxidation conditions and water quality parameters suggest that strategies to reduce NDMA formation should vary with drinking water sources and choose optimal ozone dosage.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available