Octanoic acid, zinc salt, basic

Phototransformation in air

Link to relevant study record(s)

Reference

Endpoint:

phototransformation in air

Type of information:

(Q)SAR

Adequacy of study:

key study

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:

This endpoint study record is a QSAR prediction. The estimated value of atmospheric half-life is sufficient to fulfil the information requirements as further explained in the provided endpoint summary. The reliable documentation of the applied method (QMRF) is attached under “Attached justification” in this endpoint summary.

Qualifier:

equivalent or similar to guideline

Guideline:

other: REACH guidance on QSARs R.6, May 2008

Principles of method if other than guideline:

AOPWIN v1.92 model is based on the Structure-Activity Relationships (SAR). It estimates the gas-phase reaction rate for the reaction between the most prevalent atmospheric oxidant, hydroxyl radicals, and a chemical. Gas-phase ozone radical reaction rates are also estimated for olefins and acetylenes. Atmospheric half-lives for each chemical are automatically calculated using assumed average hydroxyl radical and ozone concentrations.

GLP compliance:

no

DT50:

15 372 h

Remarks on result:

other: QSAR calculation

DT50:

641 d

Remarks on result:

other: QSAR calculation

Applicability domain:

Octanoic acid is a carboxylic acid which is within the domain of the AOPWIN v1.92 database. It does not contain any additional functional groups or fragments that are not represented by the compounds applied in the training set.

Uncertainty of prediction:

The QSAR result of octanoic acid can be considered as valid.

For more information please refer to the attached QMRF document under "Attached justification" in this endpoint summary.

Validity criteria fulfilled:

yes

Conclusions:

The atmospheric half-life was calculated with 15,372 hours (641 days) for octanoic acid. The DT50 was estimated using AOPWIN v1.92. Octanoic acid is a carboxylic acid which is within the domain of the AOPWIN v1.92 database. It does not contain any additional functional groups or fragments that are not represented by the training set compounds.

Executive summary:

Information on the atmospheric half-life is not an information requirement according to Regulation (EC) 1907/2006 Annex VII - X. However,degradation of unsaturated hydrocarbons by reaction with sunlight in the presence of oxygen can be a significant removal process where such substances are present in or near the surface of water. Hence, atmospheric half-life for octanoic acid was calculated.

Description of key information

The atmospheric half-life was calculated with 15,372 hours (641 days) for octanoic acid.