If you are on public water supply system that is using chloramines to help disinfect and maintain a disinfection residual in your tap water, you may have been consuming  chloronitramide anion (ClN₂O₂^-).  This is a nitrogen-chlorine compound and this anion forms as part of the decomposition of chloramine and dichloramine in the presence of organic material in the drinking water distribution system, piping network, and household plumbing.   Based on this information, this compound is more likely to be present in City Drinking Water or Tap Water that has been disinfected using chloramines.  (Recent Study: Chloronitramide anion is a decomposition product of inorganic chloramines).

What does this mean?

1. Currently, we do not know the toxicity of this new anion?
   
   
2. Only limited testing and characterization of this anion has been completed, i.e., only 10 public water systems that use chloramines were tested. The median concentration was 0.023 mg/L with a range of 0.013 to 0.092 mg/L.
   
   
3. It was not detected in ultrapure water or drinking water treated with a disinfectant other than chlorine.
   
   
4. Drinking chlorinated water has been associated with a few forms of cancer, i.e., colon and bladder cancer.
   
   
5. At this point there are no clear studies that have confirmed chloronitramide anion creates a human health hazard, but this means there are no studies that shows it is safe.
   
   
6. Carbon filtration may help the reduction of the chloramines in the water, but may not effectively remove the chloronitramide ions. In addition, carbon filtration may reduce the disinfection residual of the water that attempts to prevent or inhibit regrowth in a distribution system. This regrowth may become a source of total organic carbon that may contribute to the formation of this ion, plus permit the growth of nuisance and potential disease causing bacteria.
   
   
7. Available data suggests that reverse osmosis treatment systems may reduce the chloronitramides ion by 50 to 80 % (Source).
   
   
8. Chloronitramides ion is an emerging contaminant of concern, but it appears the best approach at this time is one that includes the awareness of the potential risk based on the water source and level of treatment, but a multiple barrier, in your home or business, may be a wise approach.

What should be done?  (First DO NOT PANIC)

1. If you are on a public water supply system, it would be wise to determine if the system is using chlorine or chloramines as a disinfection agent. “Because chloronitramide anion is inherent with chloramine use, water utilities that use chloramines as a secondary disinfectant should expect chloronitramide anion in their water to some extent. Although the toxicity is currently unknown, measured chloronitramide ion concentrations and similarity to other compounds with known toxicity raise concerns.” (Source: https://www.epa.gov/sciencematters/international-research-collaboration-identifies-previously-unknown-chemical-compound)
   
   
2. If the system is using chlorine or chloramines, it may be wise to get your water testing for trihalomethanes and other disinfection by-products. It would be wise to review of copy of the Consumer Confidence Report for your system).
   
   
3. It may be wise to consider the installation of a combination of a whole-house and a point of use filter includes a carbon block filter, UV light, and ion select anionic resin, but please keep in mind most water treatment systems have not been specifically tested to remove chloronitramide from the water. (Source: https://www.epa.gov/sciencematters/international-research-collaboration-identifies-previously-unknown-chemical-compound)
   
   
4. It may be wise to at least flush to waste the main water line servicing your home and the water piping in your home (Public Water Systems). 

The author of the original study suggests that a possible interim barrier may be the use of a carbon filter and /or a distillation system.  

Getting Your Water Tested - Since it is rather difficult to get the water tested for the chloronitramide ion, we recommend getting your CITY Drinking Water Testing for disinfection by-products. 

Point-of-Use Approach

Distillation System - Treat Water Used for Direct Consumption

Counter Top Distillation Systems

Point of Use Filters with Anionic Resin

These POU (point of use) filters provide quality filtered water at or near any water line. The point of use filters can be used to remove chloramines and other precursors and possibly select ions. With changeable cartridges, these filters are easy to use, maintain, and long-lasting.   These are normally multiple stage filters that include activated carbon and anion resins. Anion exchange resins have a net positive charge with negatively charged ions like chloride and hydroxide ions readily available for exchange.  (Note: Anion exchange resins are vulnerable to elevated levels of chlorine).  Because of the weak anion charge on the chloronitramide ion, the removal of this ion by ion exchange may be limited, but a fluoride based resin may be effective (Just a Hypothesis).  Because of this situation, the final treatment barrier may need to include a reverse osmosis treatment system. 

Customized Point of Use Filters 

Crystal Quest Point of Use Filters with anion resins and GAC media (may have limited effectiveness). 

Whole House Applications

Possibly the Crystal Quest Smart Water System – It may be wise to add a UV disinfection system to inhibit bacterial regrowth,  and a final barrier being the reverse osmosis system. 

or

The US Water Systems Whole House Filter Body Guard Unit, but it would be wise to add the Pulsar UV Disinfection System and a Reverse Osmosis treatment system  "What this all means is not exactly clear, but I take comfort in knowing that we have the technology to remove these types of contaminants with products like our Bodyguard and reverse osmosis systems. While I cannot predict what the ultimate solution might be, we have the technology TODAY to solve these (and many more) water problems." (Source)

UV Disinfection System (Whole House)

Crystal Quest UV Disinfection System

or

US Water Systems - UV Disinfection System with Monitor (make sure to install a 1 to 5 micron whole house particle filter before the UV disinfection system)

or

FilteredWater.com - GAC Whole House Filter with Add on UV Disinfection and post Reverse Osmosis Unit.  

Additional Resources

Chloronitramide anion is a decomposition product of inorganic chloramines

Anion Exchange Resins (More Information)

Ion Exchange Resins

Quick Guide: Trihalomethanes and HAA5/HAA9

Quick Guide: Chlorine and Chloramine in Drinking Water

Emerging Compounds

Water Testing for Reverse Osmosis Water Treatment Systems

 Other Blog Posts

Feedback and Analysis on the Safety of Fluoride in Drinking Water

Public Water Users - You Might Need a Customized Point-of-Use Water Filtration System

The Best Drinking Water Testing Kits