Reaction mass of calcium disilicide and calcium silicide

Endpoint summary

Additional information

Calcium and silicon are one of the major elemental species and present in several primary and secondary minerals in soils and Ca is essential nutrient for almost all and Si for some soil living and aquatic species.

The main constituents of CaSi are not known to bioaccumulate in aquatic, sediment or soil species at harmful levels. Certain species may actively concentrate Si and Ca in their body and both elements are essential elements or beneficial nutrients. Some species or life stages may still be naturally/ecologically sensitive to direct or indirect effects caused by too high or too low background levels of these elements.

SiliconThe inorganic Si species have no tendency or low intrinsic tendency for bioconcentration and bioaccumulation if taken up passively by organisms. Silicic acid Si(OH)₄is known to be the major bioavailable form for aquatic organisms and it plays an important role in the biogeochemical cycle of Si. For some species Si is essential element taken up actively, while for others Si is not essential but still taken passively (Si transport and distribution follows that of water) and need to be excreted out or passivated by way or other. Silicon is known to not be bio concentrated or bio accumulated to aquatic or terrestrial organisms at harmful levels.

CalciumThe behavior and accumulation potential of Ca is well known, since the element is very common in the environment and found also allover in biota. It has been observed that Ca ingested and absorbed via diet partitions rapidly to skeletons of vertebrate animals and shells of aquatic invertebrates. The ionic form is considered to be bioavailable (e.g. for plants). Calcium is not known to be bio concentrated or bio accumulated to aquatic organisms at harmful levels.

Biomagnification

Silicon or calcium do not have tendency to biomagnify (i.e. accumulate and enrich in the food chain),

Minor constituents and impurities

Depending on raw materials and purity of CaSi, products may contain also some metals > 0.1% (Fe, Al, Mn, Ti,) or non metals (C as carbides) recognised by the registration (ID card) or metals at < 0.1% level and not completely covered (recognised) by this CSA. Some of the < 0.1 % impurity metals are known to be bioaccumulative and may have effects relevant for the food chain and secondary poisoning. 

Companies should have regular control over the levels of hazardous impurities and update the chemical safety assessment and risk management measures accordingly.

Aquatic bioaccumulation is an information requirementunder Annex IX:Bioaccumulation in aquatic species, preferably fish, (9.3.2.).CaSi is an inorganic alloy and testing of these alloys for bioaccumulation is not relevant, because sufficient information of bioaccumulation potential of this material and its constituents is already available.