Abstract
N-Nitrosamines are key contaminants of concern for wastewater reuse. Although research has focused on N-nitrosodimethylamine (NDMA), measurements indicate that NDMA accounts for only ∼9% of total N-nitrosamines in wastewaters, similar to previous findings in drinking and recreational waters. Recognizing the limited time scale for biological transformation during wastewater treatment, we targeted N-nitrosodiethanolamine (NDELA) as a component of total N-nitrosamines based upon the widespread usage of its triethanolamine precursor in consumer products. NDELA accounted for ∼6% of total N-nitrosamines, exceeding NDMA concentrations in some cases, and those of all other specific N-nitrosamines measured. While ozone and chloramines increased NDMA concentrations by up to an order of magnitude, and chloramines increased NDELA concentrations in some cases, other N-nitrosamine concentrations did not increase. Total N-nitrosamine concentrations increased by only 38-89% during ozonation and 23-65% during chloramination, suggesting that, in wastewaters, the occurrence of N-nitrosamines upstream of disinfection may be more significant than their formation as disinfection byproducts. In three advanced treatment trains, reverse osmosis and UV/hydrogen peroxide advanced oxidation reduced the levels of specific N-nitrosamines below their quantification limits, although 13-30 ng/L as NDMA of uncharacterized total N-nitrosamines remained.
Original language | English (US) |
---|---|
Pages (from-to) | 54-58 |
Number of pages | 5 |
Journal | Environmental Science and Technology Letters |
Volume | 2 |
Issue number | 3 |
DOIs | |
State | Published - Mar 10 2015 |
Externally published | Yes |
ASJC Scopus subject areas
- Water Science and Technology
- Pollution
- Waste Management and Disposal
- Health, Toxicology and Mutagenesis
- Ecology
- Environmental Chemistry