Registration Dossier

Physical & Chemical properties

Partition coefficient

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

The experimentally derived log Pow of thymol is 3.3 (handbook data) which is supported by QSAR estimation giving log Kow to be 3.5161 (EPIWIN). Experimental data are assumed to be more realistic and, therfore, are used as key data.

Key value for chemical safety assessment

Log Kow (Log Pow):
3.3

Additional information

Since handbook data do not adequately fulfill the requirements for data quality these were completed by QSAR estimation with a scientifically validated and reliable model. The substance falls within the applicability domain of the model, results are adequate for risk assessment and the applied method is adequate and reliably documented.

Handbook data and QSAR estimation are evaluated in a weight-of-evidence approach and experimentally derived handbook data are shown to be comparable to estimation. Since experimental data are expected to be even more reliable than calculated ones these are used as key data and taken forward to risk assessment.

Furthermore, using the slightly lower experimental log Kow from handbook data has no significant influence on risk assessment, e.g. RCR <1 or PBT assessment.