Reaction mass of calcium dihydroxide and calcium peroxide

Endpoint summary

Key value for chemical safety assessment

Effects on fertility

Description of key information

Screening test. Data waiving (study scientifically not necessary): It has been shown that hydrogen peroxide is rapidly metabolised in the body to oxygen and water and does not bioaccumulate. In none of the repeated dose studies described in the dossier, hydrogen peroxide causes directly systemic effects. It is also doubtful whether hydrogen peroxide would reach inner organs as ovaries and testes as well as foetuses to cause reproductive and/or developmental toxicity. It is concluded that reproductive and developmental toxicity studies will not provide any additional useful information for the risk assessment of hydrogen peroxide and should therefore not be conducted due to animal welfare reasons.

Under physiological conditions, calcium oxide ultimately dissociates into Ca2+ and OH-. Calcium, as an essential and abundantly available mineral nutrient, is not deemed to be toxic to reproduction/fertility. OH- is neutralised in body fluids, hence not relevant in terms of toxicity to reproduction/fertility.

EOGRTS. Data waiving (study scientifically not necessary): According to the column 1 of REACH Annex IX, this study does not need to be conducted because the available repeated dose toxicity studies do not indicate adverse effects on reproductive organs or tissues nor reveal any other concern in relation with reproductive toxicity.

Link to relevant study records

Reference

Reference 1

Endpoint:

screening for reproductive / developmental toxicity

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Justification for type of information:

JUSTIFICATION FOR DATA WAIVING
It has been shown that hydrogen peroxide is rapidly metabolised in the body to oxygen and water and does not bio-accumulate. In none of the repeated dose studies described in the dossier hydrogen peroxide causes directly systemic effects. It is also doubtful whether hydrogen peroxide would reach inner organs as ovaries and testes as well as foetuses to cause reproductive toxicity. It is concluded that reproductive toxicity studies will not provide any useful information for the risk assessment of hydrogen peroxide and should therefore not be conducted due to animal welfare reasons.

Reproductive effects observed:

not specified

Reference 2

Endpoint:

extended one-generation reproductive toxicity - basic test design (Cohorts 1A, and 1B without extension)

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the extended one-generation reproductive toxicity study does not need to be conducted because there are no results from available repeated dose toxicity studies that indicate adverse effects on reproductive organs or tissues, or reveal other concerns in relation with reproductive toxicity

Justification for type of information:

JUSTIFICATION FOR DATA WAIVING
According to the column 1 of REACH Annex IX, the extended one generation reproductive toxicity study does not need to be conducted because the available repeated dose toxicity studies do not indicate adverse effects on reproductive organs or tissues nor reveal any other concern in relation with reproductive toxicity.

Effect on fertility: via oral route

Endpoint conclusion:

no study available

Effects on developmental toxicity

Description of key information

Data waiving (study scientifically not necessary): It has been shown that hydrogen peroxide is rapidly metabolised in the body to oxygen and water and does not bioaccumulate. In none of the repeated dose studies described in the dossier, hydrogen peroxide causes directly systemic effects. It is also doubtful whether hydrogen peroxide would reach inner organs as ovaries and testes as well as foetuses to cause reproductive and/or developmental toxicity. It is concluded that reproductive and developmental toxicity studies will not provide any additional useful information for the risk assessment of hydrogen peroxide and should therefore not be conducted due to animal welfare reasons.

Link to relevant study records

Reference

Endpoint:

developmental toxicity

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Justification for type of information:

JUSTIFICATION FOR DATA WAIVING
It has been shown that hydrogen peroxide is rapidly metabolised in the body to oxygen and water and does not bio-accumulate. In none of the repeated dose studies described in the dossier hydrogen peroxide causes directly systemic effects. It is also doubtful whether hydrogen peroxide would reach inner organs as ovaries and testes as well as foetuses to cause reproductive toxicity. It is concluded that reproductive toxicity studies will not provide any useful information for the risk assessment of hydrogen peroxide and should therefore not be conducted due to animal welfare reasons.

Species:

rat

Abnormalities:

not specified

Developmental effects observed:

not specified

Effect on developmental toxicity: via oral route

Endpoint conclusion:

no study available

Mode of Action Analysis / Human Relevance Framework

Calcium peroxide when in contact with water, on the one hand hydrolyses into hydrogen peroxide, and on the other hand results in a loss of active oxygen. Moreover, dissolving calcium peroxide in water, results in an increase of the pH. Under acidic conditions, the water solubility of the reaction mass will be very high because the hydroxide reacts with the acid.

CaO₂  + H₂O → CaO + H₂O₂

2CaO₂→ 2CaO + O₂

2CaO₂+ 2H₂O → 2Ca²⁺+ 4OH^- + O₂

 

The toxicity of the reaction mass is due to the hydrolysis product hydrogen peroxide (H2O2) and calcium hydroxide (Ca(OH)2). Under physiological conditions, calcium hydroxide ultimately dissociates into calcium cations (Ca2 +) and hydroxyl anions (OH-). Calcium, is an essential and abundantly available mineral nutrient. Hydroxyl anion is neutralised in body fluids.

Justification for classification or non-classification

Based on available information, the substance is not classified for toxicity to reproduction according to the CLP Regulation (EC) no. 1272/2008.