Occurrence of N-nitrosamines in Alberta public drinking-water distribution systems

Abstract

Since the 1974 discovery of trihalomethanes as disinfection by-products (DBPs) in drinking water, the regulatory and public health focus has been primarily directed at halogenated compounds, even though it is well established that chlorination and chloramination also produce non-halogenated DBPs. Specific halogenated DBPs that could reasonably explain the correlation of some adverse health outcomes with consumption of disinfected drinking water in a number of epidemiologic studies have yet to be identified. We therefore explored an emerging class of non-halogenated DBPs, N-nitrosamines, which warrant consideration given public health concerns regarding possible correlations of bladder cancer with exposure to chlorinated drinking water. We developed a dual media (Ambersorb® 572 and LiChrolut® EN), off-line, solid-phase extraction method that utilized a modified commercially-available extraction manifold combined with our previous GC–MS ammonia positive chemical ionization (PCI) quantitative method for analyzing N-nitrosamines in drinking water. We surveyed 20 Alberta municipal drinking-water distribution systems for the presence of N-nitrosodimethylamine (NDMA) and seven other N-nitrosamine species. Analytical results revealed the occurrence of NDMA (up to 100 ng/L) as well as two other N-nitrosamines (N-nitrosopyrrolidine and N-nitrosomorpholine) within select Alberta drinking water supplies.Key words: Alberta, chloramination, disinfection by-products, distribution system, drinking water, N-nitrosamines, NDMA, public health, survey.

Occurrences of nitrosamines in chlorinated and chloraminated drinking water in three representative cities, China

“…These findings are very similar to those observed when NDMA was investigated in distribution system water collected from 21 North American DWTPs (Barrett et al, 2003). However, an investigation of 20 municipal drinking water distribution systems in Alberta, Canada and 179 DWTPs in Ontario revealed NDMA concentrations of up to 100 ng/L and 66 ng/L, respectively (Charrois et al, 2007). As shown in Fig.…”

“…Nitrosamines as emerging DBPs have become a concern of research recently, they have been shown to be present in meats, beers, pickles, tobacco smoke and may cause adverse effects on human health (IARC, 1978;Richardson, 2009). Nitrosodimethylamine (NDMA) was initially identified as a type of DBPs in drinking water in Ontario, Canada, in 1989(Charrois et al, 2007, and as a groundwater contaminant at a northern California aerospace facility in 1998 (Najm and Trussell, 2001). In the last 10 years, the majority of studies of DBPs have focused on NDMA because it is most frequently detected in drinking water.…”

“…NDMA was initially found in trace amounts and below the limit of detection in the source water in previous studies (Krasner et al, 2006;Charrois et al, 2007). However, significant amounts of NDMA were detected in both finished water from drinking water treatment plants (DWTPs) (up to 100 ng/L) and distributed water (66 ng/L), which can be mainly attributed to the use of chlorine and chloramines for disinfection (Charrois et al, 2007).…”

“…However, significant amounts of NDMA were detected in both finished water from drinking water treatment plants (DWTPs) (up to 100 ng/L) and distributed water (66 ng/L), which can be mainly attributed to the use of chlorine and chloramines for disinfection (Charrois et al, 2007). A nationwide survey of NDMA in raw water for DWTPs in Japan indicated that it was present at levels as high as 2.6 ng/L in the summer and 4.3 ng/L in the winter (Asami et al, 2009).…”

Occurrence and profiling of multiple nitrosamines in source water and drinking water of China

“…The occurrence of these chemicals in source water, especially NDMA, NDEA and NDBA, is significantly different from previous investigations showing very low concentrations in source waters of other countries. Most of these surveys indicated that only NDMA but no other nitrosamines was detected with lower concentrations, such as in Southeastern America (b MDL) (Uzun et al, 2015) and North America (up to 9.4 ng/L), Canada (Ontario, up to 8.0 ng/L) (Barrett et al, 2003;Charrois et al, 2007;Qian et al, 2015), and Japan (up to 4.3 ng/L) (Asami et al, 2009); besides that, Zhao et al (2008) ever reported higher concentrations of NDMA occurrence in six source waters from Canada and the United States (up to 53 ng/L). The results in our survey indicated the presence of extensive discharge sources.…”