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Physical & Chemical properties

Partition coefficient

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Description of key information

The partition coefficient log Pow of the test substance was determined to be log Pow = 2.36 at 22 °C

Key value for chemical safety assessment

Log Kow (Log Pow):
2.36
at the temperature of:
22 °C

Additional information

A study was conducted in accordance with OECD TG 117 and Regulation (EC) No 440/2008 method A.8 to determine the partition coefficient of the test substance. Using the HPLC method partition coefficient Pow was determined in two individual measurements. Therefore a stock solution of the test item in methanol was prepared. A test solution was prepared by dilution the mobile phase (55 % methanol and 45 % water (v/v). The resulting solution of 10 mg/L pH 6-7 was directly measured via HPLC-UV at 22 ± 1 °C. The reference items were measured twice, once before and once after the measurement (double injection of one replicate) of the test item. The void time of the HPLC system was determined with sodium nitrate. For each reference item, the capacity factor K was calculated from the retention time of sodium nitrate and the retention time of the respective reference item. A calibration function (log K versus log Pow, linear fit) was determined using the literature values for Pow of the reference items and the retention times in the six determinations. Two individual log POW values for the test item were derived under consideration of the first and second calibration. Finally, a mean value was calculated from these individual log POW values. The coefficient of determination r2 of the calibration function log K/Log Pow was calculated to be 0.9836 and 0.9850 respectively. According to the guideline criteria these value was considered as sufficient to use the calibration function for the determination of the log Pow of the test item. The retention time of the test item lied within the range of the reference items. The log Pow of the test substance was determined to be 2.36 at 22 °C. All validation criteria ere fulfilled and no observations were made which might cause doubts concerning the validity of the study outcome.