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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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.

Diss Factsheets

Environmental fate & pathways

Adsorption / desorption

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Administrative data

Link to relevant study record(s)

Reference
Endpoint:
adsorption / desorption: screening
Type of information:
(Q)SAR
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
Calculation of the log Koc to determine the potential for adsorption/desorption of chemicals is acceptable provided that a recognised and scientifically robust methos is used. The TGD includes a method for calculating a log Koc QSAR using the log Kow. This approach is considered to be acceptable with restrictions.
Justification for type of information:
A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.
Reason / purpose for cross-reference:
read-across: supporting information
Principles of method if other than guideline:
Calculated from Log Kow 4 and the TGD calculation of Koc = 0.81.Log Kow + 0.1.
GLP compliance:
no
Remarks:
Not applicable
Type of method:
other: QSAR
Media:
other: Not applicable
Specific details on test material used for the study:
Details on properties of test surrogate or analogue material (migrated information):
Not reported
Test temperature:
Not reported
Details on study design: HPLC method:
Not reported
Details on sampling:
Not reported
Details on matrix:
Not reported
Details on test conditions:
Not reported
Computational methods:
Not reported
Key result
Type:
Koc
Value:
2 187.76
Remarks on result:
other: Temperature and pH not specified
Key result
Type:
log Koc
Value:
3.34
Remarks on result:
other: Temperature and pH
Details on results (HPLC method):
Not reported
Adsorption and desorption constants:
Not reported
Recovery of test material:
Not reported
Concentration of test substance at end of adsorption equilibration period:
Not reported
Concentration of test substance at end of desorption equilibration period:
Not reported
Details on results (Batch equilibrium method):
Not reported
Statistics:
Not reported
Validity criteria fulfilled:
not applicable
Remarks:
Not applicable for QSARs
Conclusions:
N-hexane has a log Koc of 3.34.
Executive summary:

The Koc of N-hexane was calculated from Log Kow 4 using the TGD calculation of Koc = 0.81 . Log Kow + 0.1. The log koc of n-hexane is 3.34 and Koc of 2187.76. This calculation is considered reliable for assessment for the adsorption of hexane.

Description of key information

The log Koc for 2,2-dimethylbutane is calculated to be 3.15. The bioconcentration potential of 2,2-dimethylbutane was estimated using the Episuite program v 4.11 provided by the US EPA. This QSAR model is well documented and peer reviewed. The input parameters included: CAS Number: 75-83-2 and a log Kow of 3.82.

To support this data are read-across from n-Hexane to 2,2 -dimethylbutane based on an analogue approach.

The log Koc of n-hexane was calculated to be 3.34.

Key value for chemical safety assessment

Koc at 20 °C:
2 065

Additional information

[LogKoc: 3.31]