Concerning! What is in your tap water?
Is not tap water one of the most analyzed and monitored substances (besides blood) in the world?
If it is any consolation, the average concentration of this chemical is only 23 micrograms per liter.
"After eluding chemists for 40 years, a mystery compound found in drinking water has finally been identified.
The compound – called chloronitramide anion – is previously unknown to science. ...
The mystery molecule has a very simple structure, by chemical standards: Cl-N-NO2–. ...
The researchers identified it in 40 samples of tap water from the USA, at an average concentration of 23 micrograms, or 0.00023 grams, per litre. ..."
From the perspective abstract:
"Chemical disinfection of public water supplies is one of the 20th century’s greatest public health achievements. In industrialized countries, serious waterborne illness, once a common way to die, is now rare. Inorganic chloramines (primarily NH2Cl and NHCl2) are chlorine-based disinfectants widely used in the US to disinfect water. This group of chemical compounds has weaker disinfection capability than chlorine (1) but produces lower concentrations of harmful halogenated disinfection by-products (2). However, chloramines, unlike chlorine, spontaneously decompose over timescales relevant to water distribution systems. For decades, one of the chloramine decomposition products remained uncharacterized, referred to simply as an “unidentified product” that had eluded the best efforts of chemists until now. ... Fairey et al. report that the mysterious product of chloramine decomposition is chloronitramide anion, a surprisingly stable and potentially toxic compound."
From the editor's note and abstract:
"Editor’s summary
Municipal drinking water in the US is often treated with chloramines to prevent the growth of harmful microorganisms, but these molecules can also react with organic and inorganic dissolved compounds to form disinfection by-products that are potentially toxic. Fairey et al. studied a previously known but uncharacterized product of mono- and dichloramine decomposition and identified it as the chloronitroamide anion ... This anion was detected in 40 drinking water samples from 10 US drinking water systems using chloramines, but not from ultrapure water or drinking water treated without chlorine-based disinfectants. Although toxicity is not currently known, the prevalence of this by-product and its similarity to other toxic molecules is concerning. ...
Abstract
Inorganic chloramines are commonly used drinking water disinfectants intended to safeguard public health and curb regulated disinfection by-product formation. However, inorganic chloramines themselves produce by-products that are poorly characterized. We report chloronitramide anion (Cl–N–NO2−) as a previously unidentified end product of inorganic chloramine decomposition. Analysis of chloraminated US drinking waters found Cl–N–NO2− in all samples tested (n = 40), with a median concentration of 23 micrograms per liter and first and third quartiles of 1.3 and 92 micrograms per liter, respectively. Cl–N–NO2− warrants occurrence and toxicity studies in chloraminated water systems that serve more than 113 million people in the US alone."
Researchers Identify Previously Unknown Compound in Drinking Water (original news release)
The chloramine dilemma "A decades-long drinking-water disinfection mystery ends with a potentially toxic surprise"
Chloronitramide anion is a decomposition product of inorganic chloramines (no public access)
The first author of the paper Julian Fairey
No comments:
Post a Comment