Analysis of water chemistry

Typical parameters for ensuring that unpolluted surface waters remain within acceptable chemical standards include pH, major cations and anions including ammonia, nitrate, nitrite, phosphate, conductivity, phenol, chemical oxygen demand (COD) and biochemical oxygen demand (BOD).

Monitoring the quality of the wastewater discharged from industrial premises is a key factor in controlling and minimizing pollution of the environment.

Where the nuclear industry makes wastewater discharges to rivers which have drinking water abstraction on them, radioisotopes which could potentially be harmful or those with long half-lives such as tritium will form part of the routine monitoring suite.

To ensure consistency and repeatability, the methods use in the chemical analysis of water samples are often agreed and published at a national or state level.

While some methods can be performed with standard laboratory equipment, others require advanced devices, such as inductively coupled plasma mass spectrometry (ICP-MS).

Such forensic work can examine the ratios of various components and can "type" samples of oils or other mixed organic contaminants to directly link the pollutant with the source.

In drinking water supplies the cause of unacceptable quality can similarly be determined by carefully targeted chemical analysis of samples taken throughout the distribution system.