Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

The magnesium peroxide that is present in the reaction mass of magnesium carbonate and magnesium hydroxide and magnesium oxide and magnesium 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 magnesium hydroxide 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 magnesium hydroxide 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.

 

Magnesium hydroxide

No studies are available that assess the toxicity of magnesium hydroxide to soil organisms. Nevertheless, based on its physicochemical properties and read-across data available for magnesium sulphate, magnesium hydroxide was found to have low toxicity to soil macroorganisms and terrestrial arthropods (tubificid worms, roundworms, mosquitoes and ground beetles).

The PNEC soil derived in the REACH registration dossier for magnesium hydroxide is based on the partition coefficient method using the PNEC freshwater and the log Kd value as input parameters, and was calculated to be 0.01912 mg/kg soil (dry weight).