Reaction Mass of 1,4-dimethyl-7-(prop-1-en-2-yl)-1,2,3,4,5,6,7,8-octahydroazulene and 3,8-dimethyl-5-(prop-1-en-2-yl)-1,2,3,3a,4,5,6,7-octahydroazulene and 4,8a,9,9-tetramethyldecahydro-1,6-methanonaphthalen-1-ol

Partition coefficient

Description of key information

Measured values for the test item, Patchouli oil:
Log Pow 3.2 to 5.7 for peaks 1-3 at 35 °C (OECD 117)
Log Pow > 5.7 for peaks 4 to 10 at 35 °C (OECD 117)

Estimated value for patchouli alcohol entered as key value for the purpose of environmental risk assessmment.

Key value for chemical safety assessment

Log Kow (Log Pow):

3.98

Additional information

The HPLC chromatogram of the test material showed a large number of peaks, corresponding to n-octanol/water partition coefficients ranging from 1.8 to more than 5.7. Peaks with a relative peak area of more than 1% were evaluated (10 in total). A significant fraction of the test material was found to have partition coefficients above the highest limit of the calibration range.

Since a significant fraction of Patchouli Oil has partition coefficients > 5.7, the substance is considered to have the potential to bioconcentrate for classification purposes (CLP Regulation EC 1272/2008 cut-off value of ≥ 4) and to meet the screening bioaccumulation criterion (logKow > 4.5) for PBT/vPvB assessment purposes.

For the purpose of the environmental risk assessment, a singe value is required for exposure calculations. Thus the log Kow was estimated for the 3 key constituents using Kowwin v1.68. The values are 3.98 (patchouli alcohol),  6.4 (alpha-bulnesene) and 6.7 (alpha-guaiene).