From the Greek bios - life and diagnosticos - able to detect - identification of causes or factors of environmental change based on types of bioindicators with highly specific responses and relationships. Includes bioindication and biotesting.

Biotesting is the assessment (mainly under laboratory conditions) of the quality of environmental objects using living organisms.

Biological indicators are organisms that respond to changes in the environment by their presence or absence, changes in appearance, chemical composition and behaviour. In environmental monitoring of pollution, their use often provides more valuable information than direct assessment of pollution by instruments because biological indicators respond to the full range of pollution at once. In addition, because they have "memory", their responses reflect pollution over a long period of time.