Registration Dossier

Diss Factsheets

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

The calcium peroxide that is present in the reaction mass of calcium carbonate and calcium dihydroxide and calcium peroxide will hydrolyze when it comes into contact with moist. As described in the section on the environmental fate and pathways, the thus generated degradation products are calcium dihydroxide and hydrogen peroxide. The hydrogen peroxide will further decompose into oxygen and water. As a consequence, for the assessment of the terrestrial toxicity, the effects of calcium dihydroxide and hydrogen peroxide on terrestrial organisms will be taken into account.


Hydrogen peroxide

In the REACH registration dossier for hydrogen peroxide, it is concluded that hydrogen peroxide undergoes fast decomposition in soil and groundwater. This fast decomposition has been documented both in case the initial concentration of hydrogen peroxide is relatively low (close to naturally occurring concentration) and in case of much higher concentrations (several 1000 -fold) which are applied in in situ soil and groundwater remediation treatment.

For hydrogen peroxide a PNEC soil of 0.0019 mg/kg soil (wet weight) or 0.0023 mg/kg soil (dry weight) is calculated using the aquatic PNEC and the equilibrium partitioning method.

Calcium dihydroxide

For calcium dihydroxide, reliable studies are available that assess its toxicity to earthworms, plants (6 species) and microorganisms. In the REACH registration dossier it was concluded that adverse effects only occurred at high concentrations. This results in the derivation of a PNEC soil of 1080 mg/kg soil dw.