Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 215-199-1
CAS number: 1312-76-1
Due to a strong dependence on pH and
concentration which leads to a dynamic polymerisation-depolymerisation
equilibrium with speciation into a variety of mono-, oligo-, and
polymeric anions and amorphous silica, calculations on the distribution
in various environmental compartments are not feasible (HERA 2005).
Dissolved silica from commercial
soluble silicates is indistinguishable from natural dissolved silica. Of
the elemental composition of the earth’s crust, SiO2represents
about 59%. Similar percentages are obtained for many sediments and soils
(Jackson 1964 as cited in HERA 2005). Silica is found in European rivers
in mean concentrations of 7.5 mg SiO2/L (Jorgensen et al.
1991). Thus, silica is the second most abundant element on earth.
Compounds of silicon and oxygen are ubiquitous in the environment; they
are present in inorganic matter, like minerals and soils as well as in
organic matter, like plants, animals and man. By weathering of soil,
rocks and sediments and by atmospheric deposition, silica is released
into surface and ground waters from where it may be removed by
precipitation and sedimentation or taken up by living organisms,
especially diatoms. Dead sedimenting diatoms also contribute
significantly to sediment silica (diatomaceous earth). Silica is found
in all natural waters with an average concentration of 10-20 mg SiO2/L
Due to the low vapour pressure,
volatilisation is not expected.
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
Welcome to the ECHA website. This site is not fully supported in Internet Explorer 7 (and earlier versions). Please upgrade your Internet Explorer to a newer version.
Do not show this message again