Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Overview01:26

1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Overview

4.0K
Nitrous acid and nitric acids are two types of acids containing nitrogen, among which nitrous acid is weaker than nitric acid. Nitrous acid with a pKa value of 3.37 ionizes in water to give a nitrite ion and the hydronium ion.
The nitrous acid is unstable. Hence, it is formed in situ from a solution of sodium nitrite and cold aqueous acids such as hydrochloric or sulfuric acid. In an acidic solution, the –OH group of nitrous acid undergoes protonation to give oxonium ion, followed by...
4.0K
2° Amines to N-Nitrosamines: Reaction with NaNO201:20

2° Amines to N-Nitrosamines: Reaction with NaNO2

5.6K
Secondary amines react with nitrous acid to form N-nitrosamines, as depicted in Figure 1. Nitrous acid, a weak and unstable acid, is formed in situ from an aqueous solution of sodium nitrite and strong acids, such as hydrochloric acid or sulfuric acid, in cold conditions. In the presence of an acid, the nitrous acid gets protonated. The subsequent loss of water results in the formation of the electrophile known as nitrosonium ion.
5.6K
Inorganic Nitrogen Assimilation01:22

Inorganic Nitrogen Assimilation

708
Nitrogen is an essential element in biological systems, forming a crucial component of proteins, nucleic acids, and other cellular constituents. Many bacteria and archaea acquire nitrogen in the form of nitrate (NO₃⁻) or ammonia (NH₃), which are then assimilated into biomolecules through specific enzymatic pathways.Assimilatory Nitrate ReductionWhen nitrate enters the cell, it undergoes a two-step reduction process known as assimilatory nitrate reduction. Initially, the enzyme...
708
Overview of Nitrogen Metabolism01:20

Overview of Nitrogen Metabolism

12.2K
Nitrogen is a very important element for life because it is a major constituent of proteins and nucleic acids. It is a macronutrient, and in nature, it is recycled from organic compounds and stored in the form of  ammonia, ammonium ions, nitrate, nitrite, or  nitrogen gas by many metabolic processes. Many of these metabolic processes are carried out only by prokaryotes.
The largest pool of nitrogen available in the terrestrial ecosystem is gaseous nitrogen (N2) from the air, but this...
12.2K
1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Mechanism01:37

1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Mechanism

5.1K
Nitrous acid is a relatively weak and unstable acid prepared in situ by the reaction of sodium nitrite and cold, dilute hydrochloric acid. In an acidic solution, the nitrous acid undergoes protonation when it loses water to form a nitrosonium ion—an electrophile. Nitrous acid reacts with primary amines to give diazonium salts. The reaction is called diazotization of primary amines.
5.1K
The Equilibrium Constant03:10

The Equilibrium Constant

58.4K
Consider the oxidation of sulfur dioxide:
58.4K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Source-specific nitrate and nitrite intake and bladder cancer: findings from the Danish Diet, Cancer and Health Cohort.

Environment international·2026
Same author

Source-specific nitrate and nitrite intake and associations with gastric cancer in the Danish Diet, Cancer and Health Cohort.

European journal of epidemiology·2026
Same author

Associations between source-specific nitrate and nitrite intakes and metabolic dysfunction-associated steatotic liver disease in two prospective cohorts.

Clinical nutrition (Edinburgh, Scotland)·2026
Same author

Source-specific nitrate intake and incident dementia in the Danish Diet, Cancer and Health Study.

Alzheimer's & dementia : the journal of the Alzheimer's Association·2025
Same author

Prenatal exposure to arsenic in drinking water and type 1 diabetes in a nationwide population-based cohort of Danish children.

Environment international·2025
Same author

A Review of the Evidence of the Toxicity of Chemical Substances Included in the European Union Ambient Air Quality and Drinking Water Directives: Perspectives for Health Impact Assessments.

Environment & health (Washington, D.C.)·2025

Related Experiment Video

Updated: Mar 6, 2026

Automated, High-resolution Mobile Collection System for the Nitrogen Isotopic Analysis of NOx
07:14

Automated, High-resolution Mobile Collection System for the Nitrogen Isotopic Analysis of NOx

Published on: December 20, 2016

12.1K

Nitrate, Nitrite, and Ammonium Variability in Drinking Water Distribution Systems.

Jörg Schullehner1,2, Leslie Stayner3, Birgitte Hansen4

  • 1Geological Survey of Denmark and Greenland (GEUS), C.F. Møllers Allé 8, 8000 Aarhus C, Denmark. jsc@geus.dk.

International Journal of Environmental Research and Public Health
|March 12, 2017
PubMed
Summary

Drinking water nitrate levels are consistent within distribution systems and show no seasonal changes. Measurements at waterworks exits accurately reflect consumer exposure, simplifying health studies.

Keywords:
Denmarkammoniumdrinking waterexposure assessmentnitratenitrificationnitrite

More Related Videos

Measurement of the Potential Rates of Dissimilatory Nitrate Reduction to Ammonium Based on 14NH4+/15NH4+ Analyses via Sequential Conversion to N2O
08:05

Measurement of the Potential Rates of Dissimilatory Nitrate Reduction to Ammonium Based on 14NH4+/15NH4+ Analyses via Sequential Conversion to N2O

Published on: October 7, 2020

6.7K
Measuring Nitrite and Nitrate, Metabolites in the Nitric Oxide Pathway, in Biological Materials using the Chemiluminescence Method
08:25

Measuring Nitrite and Nitrate, Metabolites in the Nitric Oxide Pathway, in Biological Materials using the Chemiluminescence Method

Published on: December 25, 2016

23.2K

Related Experiment Videos

Last Updated: Mar 6, 2026

Automated, High-resolution Mobile Collection System for the Nitrogen Isotopic Analysis of NOx
07:14

Automated, High-resolution Mobile Collection System for the Nitrogen Isotopic Analysis of NOx

Published on: December 20, 2016

12.1K
Measurement of the Potential Rates of Dissimilatory Nitrate Reduction to Ammonium Based on 14NH4+/15NH4+ Analyses via Sequential Conversion to N2O
08:05

Measurement of the Potential Rates of Dissimilatory Nitrate Reduction to Ammonium Based on 14NH4+/15NH4+ Analyses via Sequential Conversion to N2O

Published on: October 7, 2020

6.7K
Measuring Nitrite and Nitrate, Metabolites in the Nitric Oxide Pathway, in Biological Materials using the Chemiluminescence Method
08:25

Measuring Nitrite and Nitrate, Metabolites in the Nitric Oxide Pathway, in Biological Materials using the Chemiluminescence Method

Published on: December 25, 2016

23.2K

Area of Science:

  • Environmental Science
  • Public Health
  • Water Quality Analysis

Background:

  • Accurate assessment of nitrate in drinking water is vital for epidemiological studies on long-term health effects.
  • Current methods often rely on assumptions regarding variability within distribution systems and seasonal changes.
  • Nitrate exposure assessments are typically based on regulatory data, which may not fully capture consumer exposure dynamics.

Purpose of the Study:

  • To assess intra-distribution system variability of nitrate, nitrite, and ammonium concentrations.
  • To evaluate seasonal (short-term) concentration variability of these contaminants in Danish public waterworks.
  • To determine the suitability of waterworks exit measurements for estimating consumer exposure in epidemiological studies.

Main Methods:

  • Analysis of nitrate, nitrite, and ammonium concentrations from Danish public waterworks (2007-2016).
  • Comparison of contaminant levels at the waterworks exit versus within the distribution system and at consumer taps.
  • Statistical assessment of seasonal variations in contaminant concentrations.

Main Results:

  • Nitrate concentrations at waterworks exits strongly correlate with those within the distribution system and at consumer taps.
  • Nitrite and ammonium concentrations are generally lower within the distribution system than at the exit due to nitrification.
  • Nitrification leads to only a minor increase in nitrate concentrations within the distribution system.
  • No significant seasonal variation was observed for nitrate, nitrite, or ammonium concentrations.

Conclusions:

  • Nitrate measurements at waterworks exits are reliable indicators of exposure for all connected consumers.
  • Existing sampling frequencies in national monitoring programs are adequate for capturing temporal variations in longitudinal studies.
  • The findings support the use of readily available regulatory data for robust exposure assessment in public health research.