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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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: 225-863-2 | CAS number: 5124-30-1
Phototransformation in air
Administrative data
Link to relevant study record(s)
- Endpoint:
- phototransformation in air
- Type of information:
- calculation (if not (Q)SAR)
- Remarks:
- Migrated phrase: estimated by calculation
- Adequacy of study:
- key study
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- accepted calculation method
- Principles of method if other than guideline:
- Calculated with AOP Program v1.92 of EPI-Suite Software. The Atmospheric Oxidation Program (AOPWIN) estimates the rate constant for the atmospheric, gas-phase reaction between photochemically produced hydroxyl radicals and organic chemicals. The rate constants are then used to calculate atmospheric half-lives for organic compounds based upon average atmospheric concentrations of hydroxyl radicals and ozone.
- GLP compliance:
- no
- Estimation method (if used):
- PHOTOCHEMICAL REACTION WITH OH RADICALS
- sensitiser for indirect photolysis: OH radicals
- Concentration of OH radicals: 0.5 E6 OH/cm³, 24 h/d
- DT50:
- 15 h
- Test condition:
- 25 °C
- Executive summary:
The photodegradation of 4,4-methylenedicyclohexyl diisocyanate was estimated with AOPWIN v. 1.92. Based on a
OH radical concentration of 0.5 E06 OH/cm³, the atmospheric oxidation rate constant of "substance" (CAS:5124 -30 -1) is 26 * 10-12cm3/(molecule *s) and its atmospheric half-life is 15 hrs (Currenta, 2009).
Reference
A 24-hour day and an OH radical concentration of 0.5 E06 OH/cm³ are assumed for the calculation. |
Description of key information
There are no experimental data on the stability of 4,4’-methylenedicyclohexyl diisocyanate in the atmosphere.
A half-life of about 15 hours is estimated due to reaction with photochemically produced hydroxyl radicals, considering a mean OH concentration of 0.5 x 106 OH radicals/cm³ as a 24 h-average (Currenta, 2009a). However, the AOPWIN program used for this estimate does not take into account that 4,4’-methylene- dicyclohexyl diisocyanate is sensitive to hydrolysis e.g. in aerosols with aquatic phases.
The photodegradation of the hydrolysis product of 4,4’-methylenedicyclohexyl diisocyanate was estimated with AOPWIN v. 1.92. The atmospheric oxidation rate constant of the hydrolysis product of 4,4’-methylenedicyclohexyl diisocyanate (CAS:1761 -71 -3) is 117 * 10-12cm3/(molecule *s) and its atmospheric half-life is about 3 hrs at a mean OH concentration of 0.5 x 106 OH radicals/cm³ (Currenta, 2009b).
Key value for chemical safety assessment
- Half-life in air:
- 15 h
Additional information
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.
