title: Rejection of pharmaceutically-based N-nitrosodimethylamine precursors using nanofiltration.
abstract: N-Nitrosodimethylamine (NDMA) is a disinfection by-product (DBP) with many known precursors such as amine-containing pharmaceuticals that can enter the environment via treated wastewater. Reverse osmosis and tight nanofiltration membranes (MW cutoff < 200 Da) are treatment technologies that demonstrate high removal of many compounds, but at relatively high energy costs. Looser membranes (>200 Da) may provide sufficient removal of a wide range of contaminants with lower energy costs. This study examined the rejection of pharmaceuticals that are known NDMA precursors (∼300 Da) using nanofiltration (MW cutoff ∼350 Da). MQ water was compared to two raw water sources, and results illustrated that NDMA precursors (as estimated by formation potential testing) were effectively rejected in all water matrices (>84%). Mixtures of pharmaceuticals vs. single-spiked compounds were found to have no impact on rejection from the membranes used. The use of MQ water vs. surface waters illustrated that natural organic matter, colloids, and inorganic ions present did not significantly impact the rejection of the amine-containing pharmaceuticals. This study illustrates that NDMA formation potential testing can be effectively used for assessing NDMA precursor rejection from more complex samples with multiple and/or unknown NDMA precursors present, such as wastewater matrices.
authors.affiliation: Department of Civil Engineering, University of Toronto, 35 St. George Street, Toronto, ON M5S 1A4, Canada. Electronic address: Gwen.Woods-Chabane@HDRinc.com.
authors.forename: Gwen C
authors.initials: GC
authors.lastname: Woods
authors.affiliation: Department of Civil Engineering, University of Toronto, 35 St. George Street, Toronto, ON M5S 1A4, Canada; Department of Civil, Environmental & Construction Engineering, University of Central Florida, 12760 Pegasus Drive, Orlando, FL 32816, United States.
authors.forename: A H M Anwar
authors.initials: AHMA
authors.lastname: Sadmani
authors.affiliation: Department of Civil Engineering, University of Toronto, 35 St. George Street, Toronto, ON M5S 1A4, Canada.
authors.forename: Susan A
authors.initials: SA
authors.lastname: Andrews
authors.affiliation: Department of Chemical Engineering, University of Wyoming, Dept. 3295, 1000 E. University Avenue, Laramie, WY 82071, United States.
authors.forename: David M
authors.initials: DM
authors.lastname: Bagley
authors.affiliation: Department of Civil Engineering, University of Toronto, 35 St. George Street, Toronto, ON M5S 1A4, Canada.
authors.forename: Robert C
authors.initials: RC
authors.lastname: Andrews
mesh_terms: D002700:Chloramines / Q000737:chemistry; D004128:Dimethylnitrosamine / Q000737:chemistry* / Q000302:isolation & purification; D004203:Disinfection / Q000295:instrumentation / Q000379:methods; D005374:Filtration / Q000295:instrumentation / Q000379:methods; D008567:Membranes, Artificial; D008851:Micropore Filters; D004364:Pharmaceutical Preparations / Q000737:chemistry / Q000302:isolation & purification; D011355:Prodrugs / Q000737:chemistry* / Q000302:isolation & purification; D013997:Time Factors; D062065:Wastewater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000302:isolation & purification; D018508:Water Purification / Q000295:instrumentation / Q000379:methods*
chemical_list: D002700:Chloramines; D004128:Dimethylnitrosamine; D008567:Membranes, Artificial; D004364:Pharmaceutical Preparations; D011355:Prodrugs; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Doxylamine; Formation potential; Loose membrane; NDMA; Nizatidine; Ranitidine