formula: Se; CAS Registry Number: 7782-49-2

Relatively rare element that naturally occurs both in its elemental form and in many minerals

It is commercially relevant mainly in chemical-, glass-, and electronic industry. Further fields of applications are e.g. rubber production, metal industry, food industry, medicine and agriculture.

Selenium compounds enter the environment mostly through anthropogenic activities (e.g. burning of fossil fuels like coal). Naturally Se-enriched soils are often found in the vicinity of volcanoes. It occurs in waters as a result of weathering of rocks, leaching from soils, waste waters and atmospheric deposition.

Selenium is essential for animals and some plants. Besides its physiological function as component of proteins it acts as protective agent against environmental toxins and carcinogens.

However, it also has toxic properties with often narrow concentration ranges between toxic concentrations and concentrations at which Se-deficiency occurs.

Environmentally relevant data for selenium include:

For more information about the for chemical analysis see the Guidelines for Chemical Analysis: Determination of Arsenic and Selenium in Environmental Samples by ICP-MS after Hydride Formation.


  • Common mussel species as invasive animal in rivers and lakes with high information level for water pollution
  • Bioindicator in rivers and lakes
  • Fine insoluble mineral or organic particles in the water phase
  • Common brown alga of the coastal areas of the North and Baltic Sea
  • One of the most important edible mussel species common in the North and Baltic Sea
  • As the only viviparous fish in German nearshore waters, it is a bioindicator in nearshore coastal marine ecosystems.
  • Inshore, the herring gull mainly feeds from the sea: upon fish, mussels, and crabs.
  • A major primary producer in semi-natural and anthropogenic affected ecosystems.
  • A major primary producer in semi-natural and anthropogenic affected ecosystems.
  • A deciduous tree typical of ecosystems close to dense conurbations and an indicator for the characterisation of the immission situation during the vegetation period.
  • As the most dominant deciduous tree species in Central Europe, it plays a significant role in most nearly natural and also anthropogenically influenced forest ecosystems up to an altitude of 1100 m.
  • The roe deer is the most common of the larger herbivores (first order-consumer) to be found in the wild in Europe.
  • A pigeon species home in nearly every city.
  • Student groups with an even number of female and male students at the age of 20 to 29.

Sampling area

Sampling period

1985 - 2022

Extended information

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