Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

Data on the acute toxicity of tricalcium bis(orthophosphate) (CAS 7758-87-4) are available for three trophic levels (fish, Daphnia, algae). All studies were conducted according to the internationally accepted OECD guidelines. The determined L(E)50 values were >100 mg/L (nominal), adverse effects of the substance were not observed. Tricalcium bis(orthophosphate) is therefore considered not acutely toxic to aquatic organisms. Data on the chronic toxicity are not available. The substance consists of the calcium cation and the phosphate anion. Calcium and phosphorus are essential micronutrients for aquatic organisms. They are not expected to bioaccumulate and a chronic toxicity of the ions is not anticipated. Experimental data on the toxicity of tricalcium bis(orthophosphate) to aquatic microorganisms are not available. In accordance with Annex XI, 1.5, of Regulation (EC) No 1907/2006, read-across to the structurally related substance calcium bis(dihydrogenorthophosphate) (CAS 7758-23-8) was conducted to fulfil the standard information requirements. In accordance with Article 13 (1) of Regulation (EC) No 1907/2006, "information on intrinsic properties of substances may be generated by means other than tests, provided that the conditions set out in Annex XI are met.” In particular for aquatic toxicity, information shall be generated whenever possible by means other than vertebrate animal tests, which includes the use of information from structurally related substances (grouping or read-across). According to Annex XI, Item 1.5, of Regulation (EC) No 1907/2006 substances can be considered to be similar if their physicochemical, toxicological and ecotoxicological properties are likely to be similar or follow a regular pattern as a result of structural similarity. The target and the source substance are structurally similar calcium phosphates. The substances differ in the number of calcium cations and the dissociation of the phosphate anion. Both substances are characterised by comparable physico-chemical properties. They are inorganic solids and thus not volatile. The water solubility of the target and source substance differs. However, a comparable environmental fate and ecotoxicological profile is anticipated for both substances.

The read-across study on the toxicity of calcium bis(dihydrogenorthophosphate) to aquatic microorganisms was conducted according to OECD guideline 209. Adverse effects on aquatic microorganisms were not observed. An EC50(3h)> 1000 mg/L based on the nominal test substance concentrations was determined.

Based on the available data tricalcium bis(orthophosphate) (CAS 7758-87-4) is considered not toxic to aquatic organisms.