Ethylene

Adsorption / desorption

Link to relevant study record(s)

Reference

Endpoint:

adsorption / desorption: screening

Type of information:

(Q)SAR

Adequacy of study:

key study

Study period:

Up to 2021

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

Episuite and the KOCWIN models are well documented and commonly used QSARs for predicting the biodegradation potential of chemicals. Substances within LOA fall within the applicability domain of these models and they have been recommended by ECHA in the Information Requirement Guidelines.

Qualifier:

no guideline required

Principles of method if other than guideline:

The Soil Adsorption Coefficient Program (KOCWIN) estimates the soil adsorption coeffiecient (Koc) of organic compounds.  Koc can be defined as "the ratio of the amount of chemical adsorbed per unit weight of organic carbon (oc) in the soil or sediment to the concentration of the chemical in solution at equilibrium"; it is represented by the following equation:

 Koc =  (ug adsorbed/g organic carbon) / (ug/mL solution)

The units of Koc are typically expressed as either L/kg or mL/g.

Estimated values of Koc are often used in environmental fate assessment because measurement of Koc is expensive.  Traditional estimation methods rely upon the octanol/water partition coefficient or related parameters, but the first-order molecular connectivity index (MCI) has been used successfully to predict Koc values for hydrophobic organic compounds (Sabljic, 1984, 1987; Bahnick and Doucette, 1988).

Specific details on test material used for the study:

N/A

Test temperature:

N/A

Details on study design: HPLC method:

N/A

Details on sampling:

N/A

Details on matrix:

N/A

Details on test conditions:

N/A

Computational methods:

N/A

Key result

Type:

log Koc

Remarks:

Kow method

Value:

0.98 dimensionless

Remarks on result:

other: Result from QSAR estimation

Details on results (HPLC method):

N/A

Adsorption and desorption constants:

N/A

Recovery of test material:

N/A

Concentration of test substance at end of adsorption equilibration period:

N/A

Concentration of test substance at end of desorption equilibration period:

N/A

Details on results (Batch equilibrium method):

N/A

Statistics:

N/A

N/A

Conclusions:

The estimated log Koc for this substance is 0.980.

Executive summary:

The log Koc of this substance has been estimating using EPISUITE v4.11 which is based on methodology developed by Sahljic et al. (1995) and Meylan et.al (1992). The estimated Log Koc of this substance is 0.980.

Description of key information

The log Koc of this substance has been estimating using EPISUITE v4.11 which is based on methology developed by Sahljic et al. (1995) and Meylan et.al (1992). The estimated Log Koc of this substance is 0.980.

Key value for chemical safety assessment

Koc at 20 °C:

0.98

Additional information

The log Koc of this substance has been estimating using EPISUITE v4.11 which is based on methology developed by Sahljic et al. (1995) and Meylan et.al (1992). The estimated Log Koc of this substance is 0.980.