Glossary
Analysis of water - Methods and indicators for the measurement and monitoring of aquatic pollution

Self-purification

A natural process by which aquatic environments remove or transform pollutants through biological, chemical, and physical mechanisms.

Total nitrogen (NGL)

All forms of nitrogen present in an environment, including organic and inorganic nitrogen (ammonia, nitrates, nitrites).

Biomarkers

Biological indicators used for the early detection of the toxic effects of pollutants on aquatic organisms, before sublethal or lethal effects occur.

Total Organic Carbon (TOC)

The total amount of organic carbon present in a water sample, used as an indicator of organic pollution.

Chemical Auto-Oxidation Demand (CAOD)

A measure of the slow oxidation of labile organic matter, such as lactose or nitrites, by molecular oxygen present in the water

Biochemical Oxygen Demand (BOD)

The amount of oxygen required for the biological...