Poly[oxy[(hydroxymethyl)-1,2-ethanediyl]], .alpha.-dodecyl-.omega.-hydroxy-

Adsorption / desorption

Link to relevant study record(s)

Reference

Endpoint:

adsorption / desorption: screening

Remarks:

adsorption/desorption

Type of information:

(Q)SAR

Adequacy of study:

key study

Study period:

2013

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Use of valid QSAR

Qualifier:

according to guideline

Guideline:

other: TGD QSARs for soil and sediment sorption for different chemical classes

GLP compliance:

no

Type of method:

other: QSAR estimation

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
Not applicable

Test temperature:

Not applicable

Details on study design: HPLC method:

Not applicable

Details on sampling:

Not applicable

Details on matrix:

Not applicable

Details on test conditions:

Not applicable

Computational methods:

Log Koc was calculated from Log Kow according to equations defined by Sabljic and Güsten (1995) for non hydrophobic substances as reported in the TGD, 2003:
LogKoc = 0.52 logKow + 1.02

Type:

log Koc

Value:

2.974

Details on results (HPLC method):

Not applicable

Adsorption and desorption constants:

Not applicable

Recovery of test material:

Not applicable

Concentration of test substance at end of adsorption equilibration period:

Not applicable

Concentration of test substance at end of desorption equilibration period:

Not applicable

Details on results (Batch equilibrium method):

Not applicable

Statistics:

Not applicable

The derivation of Koc from Kow values as described in the TGD (2003) is reported as a usable valid model by ECHA, which fulfilled all OECD principles:

1. A defined endpoint:

Adsorption coefficient (Koc).

2. An unambiguous algorithm:

19 models have been developed for different chemical classes (see table 4 of the TGD part III). The chemical class “predominantly hydrophobics” is defined as compounds containing only carbon, hydrogen and halogen (F, Cl, Br, I) atoms, “nonhydrophobic chemicals” being all chemicals that cannot be classified as predominantly hydrophobics. Fourteen class-specific QSAR models were produced for all nonhydrophobic classes of chemicals, in order to give more appropriate equations. For the purposes of calculations, the test substance is considered predominantly non-hydrophobics. The corresponding equation is log Koc = 0.52*log Kow + 1.02

3. A defined domain of applicability:

The applicability domain of the sorption models developed by Sabljic and Güsten (1995) depends on the considered chemical class, and is based on logKow range (see table 5 of the TGD part III). The substance is within the validity domain of predominantly non-hydrophobics.

4. Appropriate measures of goodness-of-fit, robustness and predictivity:

For non-hydrophobics: n (number of data) = 390; R² (correlation coefficient) = 0.63; s.e. (standard error of estimate) = 0.56.

5. A mechanistic interpretation, if possible:

No data

Validity criteria fulfilled:

yes

Conclusions:

The Log Koc of the substance predicted from Log Kow of 3.757 and following equations of Sabljic and Güsten (1995) for non hydrophobic substances is 2.9736 which gives a Koc of 941 L/kg.

Description of key information

For the purposes of chemical safety assessment, the organic carbon-water partition coefficient is predicted using the equations form Sabljic and Güsten (1995) for non hydrophobic substances. 

Key value for chemical safety assessment

Koc at 20 °C:

941

Additional information

The chemical safety assessment submitted as part of the previous registration dossier (2012) was conducted for the main constituent with MW of 260.42. A log Koc of 3.23 was estimated by QSAR. The chemical safety assessment is carried out for the constituents (MW of 260.42, 334.5 and 408.58) of the registered substance. A log Koc of 2.97 (Koc at 20°C: 941) was estimated by QSAR and is used as input value for the exposure assessment of environment.