Silicic acid, aluminum sodium salt

Bioaccumulation: aquatic / sediment

Link to relevant study record(s)

Reference

Endpoint:

bioaccumulation in aquatic species: fish

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Description of key information

The performance of a bioaccumulation study is scientifically not necessary.

Additional information

Bioaccumulation is not applicable because silicon dioxide/silicate, including the synthetic amorphous Silicic acid, aluminum sodium salt (CAS 1344-00-9, NAS), represents a class of inorganic compounds with a log P_ow <3. Furthermore, due to its inherent chemico-physical properties, such as the absence of lipophilicity as well as the capability of the organism to excrete absorbed silicates, bioaccumulation can be disregarded. However, silica/silicate can be actively accumulated by terrestrial plants (e.g. grass) and some marine organisms (e.g. diatoms, radiolarians, and sponges), which represents a normal natural process. Silicon is the second most abundant element in the Earth’s crust mass (approx. 28 %) after oxygen. It appears as complex silicate minerals in soils and sediments, as the oxide (silica, SiO₂) in crystalline form in rocks, soils and sand, and as biogenic silica in organisms such as diatoms, radiolarians or silicoflagellates and in plants such as grass, rushes, rice or sugar cane. Thus, organisms are already adapted to silicate, and exposure to synthetic amorphous Silicic acid, aluminum sodium salt (CAS 1344-00-9, NAS) is not expected to lead to adverse effects. The same applies to aluminum which is the third most abundant element (approx. 8%) in the Earth's crust.