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Monitoring of nitrogenated DBPS in drinking water - WT1256

Description
A recent review sponsored by the DWI gave reassuring evidence that level of nitrogen containing disinfection by product (N-DBPs) in UK drinking waters are no higher and likely to be lower than the level that have been detected on the US. This review is available on the DWI website1. In addition work conducted in Scotland2 on chloraminated supplies has reinforced this view. The review went on to recommend monitoring to support its conclusion.
The review identified a number of risk factor for each N-DBPs which included both source and treatment factors two of these were dissolved organic nitrogen levels and use of chloramination.
For many of the compounds identified, a full risk assessment is not possible because of the limited toxicological data. The purpose of this study is to monitor for the those compounds for which an adequate toxicological database is available and to also include some additional compounds to provide comparative exposure data.

The purpose of this study is conduct monitoring of drinking water in England and Wales at high risk sites for selected nitrogen containing DBPs.


Objective
The objectives are to:

Select analytical methods to use and N DBPs to monitor for, with due regard to the findings of the earlier reports. As a minimum the study will need to include dibromoacetonitrile and dichloroacetontrile for which WHO guideline values have been established. The project need not include nitrosamines as a separate project is currently underway.

Conduct appropriate performance testing for the selected analytes using the chosen methods.

Select water treatment works with due regard to the risk factors identified in previous reports. The selection should be targeted at those circumstances known or thought to give rise to the highest concentrations of the selected N-DBPs. It is recognised that different risk factors may be important for each of the groups of NDBPs selected. The selection is likely to focus on drinking water derived from surface water sources but should also include some groundwater sources. All major treatment types should be included. It is envisaged that quarterly sampling at about 20 works will give reasonable range of conditions.

Liaise with water companies to select and arrange access to appropriate sampling sites and locations.

Conduct quarterly sampling of water leaving the selected water treatment works in accordance with best practice in terms of sampling and analysis, including appropriate analytical quality control.

Gather other relevant data such as water treatment performance information and water quality data to help interpret the results.

Report the findings of the survey, comparing levels found with established health based standards or with occurrence data from other countries.

Project Documents
• FRP - Final Report : DWI70 2 268   (1772k)
• EXE - Executive Summary : DWI70 2 268exsum   (25k)
Time-Scale and Cost
From: 2011

To: 2012

Cost: £117,163
Contractor / Funded Organisations
Imperial College Consultants Ltd (IC Consultants Ltd)
Keywords
Drinking Water              
Monitoring              
Quality              
Water              
Fields of Study
Water Quality