Registration Dossier
Registration Dossier
Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.
The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.
Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 253-425-0 | CAS number: 37247-91-9
Endpoint summary
Administrative data
Description of key information
Toxicity via the oral route is addressed by upper intake levels (UL) for adults determined by the Scientific Committee on Food (SCF), being
UL = 2500 mg/d, corresponding to 36 mg/kg bw/d (70 kg person) for calcium
UL = 250 mg/d, corresponding to 3.6 mg/kg bw/d (70 kg person) for magnesium.
Toxicity of calcium magnesium oxide via the dermal route is not considered as relevant.
Toxicity of calcium magnesium oxide via inhalation (local effect, irritation of mucous membranes) is addressed by an 8-h TWA determined by the Scientific Committee on Occupational Exposure Limits (SCOEL) of 1 mg/m³.
Key value for chemical safety assessment
Additional information
Guideline compliant repeated-dose toxicity studies in rodents with oral administration of lime (28-day study acc. to OECD TG 407 or 90-day study acc. OECD TG 408) are not available. None of the five animal studies available for various calcium salts allow the derivation of a NOAEL or LOAEL for quantitative risk assessment purposes.
However, the Scientific Committee on Food has determined an upper intake level (UL) of calcium for adults of 2500 mg/d, corresponding to 36 mg/kg bw/d, taking into account an average body weight of 70 kg/person.
No relevant oral repeated-dose toxicity study for magnesium was identified. However, the Scientific Committee on Food has determined an upper intake level (UL) of calcium for adults of 250 mg/d, corresponding to 3.6 mg/kg bw/d, taking into account an average body weight of 70 kg/person.
A dermal repeated-dose toxicity study for calcium magnesium oxide is considered to be scientifically unjustified.
A repeated-dose toxicity study for calcium magnesium oxide via the inhalation route is considered to be scientifically unjustified. Instead, the adopted Recommendation from the Scientific Committee on Occupational Exposure Limits (SCOEL) for Calcium oxide (CaO) and calcium hydroxide (Ca(OH)2) has determined an 8-h TWA of 1 mg/m³ which is considered protective against adverse effects in case of long-term exposure to CaO and Ca(OH)2. Effects upon inhalation of lime are purely local, i.e. irritation provoked by a pH shift. Since calcium magnesium oxide only contains magnesium as an additional element, is less soluble and produces a lower pH shift than CaO and Ca(OH)2, the respective 8-h TWA can be adopted for calcium magnesium oxide by read-across.
Justification for classification or non-classification
The only toxicologically relevant effect of calcium magnesium oxide is local irritation through a pH shift, which is not relevant for classification for repeated-dose toxicity. Therefore, classification of calcium magnesium oxide for toxicity upon prolonged exposure is not required.
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
