Reaction mass of cobalt olivine and crystalline silicon dioxide

Endpoint summary

Description of key information

Reaction mass of cobalt olivine and crystalline silicon dioxide is moderately soluble in environmental media. Based on results of a standard transformation/dissolution test according to OECD Series No 29, the dissolution at a loading of 1 mg/L Reaction mass of cobalt olivine and crystalline silicon dioxide results at pH 6, the pH that maximises dissolution, in dissolved cobalt levels of 101 µg Co/L and 138 µg Co/L after 7 and 28 days, respectively. Thus, the rate and extent to which Reaction mass of cobalt olivine and crystalline silicon dioxide produces soluble (bio)available ionic and other cobalt-bearing species in environmental media is limited. Reaction mass of cobalt olivine and crystalline silicon dioxide contains also silicon, but silicon does not have an ecotoxic potential (see OECD SIDS Silicon dioxide, 2004), as also confirmed by the absence of respective ecotoxicity reference values in the Metals classification tool (MeClas) database (http://www.meclas.eu/ accessed on 18.04.2021). Further, the limited solubility of Reaction mass of cobalt olivine and crystalline silicon dioxide is expected to determine its behaviour and fate in the environment, and subsequently its bioavailability and potential for bioaccumulation and ecotoxicity. A conservative read-across approach is applied based on all information available for different inorganic cobalt substances and the fate of the released cobalt ions can ultimately be expected to be similar to the common fate of cobalt ions in the environment. For further information on the applied read-across approach, please refer to the RAAF document “Read-across approach for environmental toxicity of the pigments “Reaction mass of cobalt olivine and crystalline silicon dioxide” & “Olivine, cobalt silicate blue, 2021” attached in IUCLID Section 13.