Analyzing Ammonia by Ion Chromatography

Determining ammonia levels in drinking water, pharmaceuticals, and even soil

Classified as a hazardous substance under EPA regulations, ammonia is a colorless gas that carries a distinctly sharp odor. A compound of nitrogen and hydrogen molecules, it dissolves easily in water, entering environmental waters through decomposition of nitrogen-containing compounds.

Spectroscopic techniques for ammonia determination may require an additional distillation step, while ion chromatography (IC) can determine ammonium and its inorganic cations in a single run.

Regulatory information

In the U.S., the ammonium cation (NH4) is measured for wastewater discharge compliance. In the EU and Japan, ammonia is monitored in both wastewater and drinking water.

  • WHO: Recognizes ammonia odor effects at a concentration of 1.5mg/L and taste effects at 35mg/L.
  • EPA: There is no mandated Maximum Contaminant Level (MCL) for ammonia. However, ammonia is toxic to aquatic life, and annual release reporting is required, as well as immediate reporting for a release of more than 100 pounds in a 24-hour period.
  • USP: Ammonia is measured by a colorimetric assay in the USP-NF sodium bicarbonate monograph, with a 0.002% limit for ammonia in sodium bicarbonate.
  • FDA: Lists ammonia as a respiratory toxicant and requires tobacco product manufacturers to report the quantity present in their products.

Example application notes