Trifluoromethanesulphonic anhydride

Partition coefficient

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 27 November 2006 to 27 November 2007

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

The study was performed with HPLC method, but a limit test was performed instead of a full test. Furthermore, one reference item was used instead of six as specified in the Guidelines. So it cannot allow full validation compared to OECD117/EC A8 guidelines.

Qualifier:

according to guideline

Guideline:

OECD Guideline 117 (Partition Coefficient (n-octanol / water), HPLC Method)

Deviations:

yes

Remarks:

Only one reference item was used instead of six as specified in the Guideline. A limit test was performed instead of a full test, the retention of the test item was compared to the retention of a reference item.

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient)

Deviations:

yes

Remarks:

Only one reference item was used instead of six as specified in the Guideline. A limit test was performed instead of a full test, the retention of the test item was compared to the retention of a reference item.

GLP compliance:

yes (incl. QA statement)

Remarks:

2005-06-09

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Key result

Type:

log Pow

Partition coefficient:

< 0.3

Temp.:

25 °C

pH:

1

Preliminary estimation results:

Structure used for the estimation: C(F)(F)(F)S(=O)(=O)O

The results of KOWWIN estimation are shown in the following table:

Number	Log10Powfragment description	Coefficient	Value
1	-C, aliphatic carbon	0.9723	0.9723
3	-F, aliphatic attachment	-0.0031	-0.0093
1	-SO2-OH	-3.1580	-3.1580
1	-SO-C, structure correction	1.4790	1.4790
	Equation correction		0.2290

Estimated log₁₀P_ow = -0.49

Definitive test results:

Under these analytical conditions, the test item was found to elute before 2 -butanone, indicating a log₁₀P_ow value of less than 0.3.The chromatogram of 2 -butanone and of the test item are shown in Attachment1.

Conclusions:

The test item was found to have a log10Pow value of less than 0.3

Executive summary:

The determination of the partition coefficient was performed according to Method A.8 of Commission Regulation No 440/2008 of 30 May 2008, Method 117 of OECD guidelines for the Testing of Chemical and GLP.Only one reference item was used instead of six as specified in the Guidelines and a limit test was performed instead of a full test. Indeed, the retention time of the test item wasn't calculated and then used to determined the partition coefficient. In fact, the retention of the test item was compared to the retention of a reference item.

Partition coefficients in the range of log₁₀P_owbetween 0 and 6 can be estimated using high performance chromatography (HPLC). This is performed on columns containing hydrocarbon chains (e.g. C8, C18) chemically bound onto silica. The chemicals injected onto the column move along it by partitioning between the mobile solvent phase and the hydrocarbon stationary phase, their retention being proportional to their hydrocarbon-water partition coefficient. In this study a limit test was performed, a low log₁₀P_owvalue was anticipated.

The test item was found to elute before 2 -butanone, indicating a log₁₀P_owvalue of less than 0.3.

Reference 2

Endpoint:

partition coefficient

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

The read-across justification is provided in the attached document.

Reason / purpose for cross-reference:

read-across source

Key result

Type:

log Pow

Partition coefficient:

< 0.3

Temp.:

25 °C

Remarks on result:

other: By analogy with the hydrolysis product

Conclusions:

By analogy with its degradation product in water, the logKow of trifluoromethanesulfonic anhydride is considered to be below 0.3.

Description of key information

Trifluoromethanesulfonic anhydride is rapidly hydrolysed in water, therefore it is not technically possible to measure a logKow value for this substance. The logKow value of the degradation product, i.e. trifluoromethanesulfonic acid, is considered as relevant for the assessment of trifluoromethanesulfonic anhydride.

The experimental determination of the partition coefficient of trifluoromethanesulfonic acid was performed according to EU Method A.8, the OECD TG 117 and the GLP. Some deviations from the Guidelines were observed. Only one reference item was used instead of six as specified in the Guidelines and a limit test was performed instead of a full test. Indeed, the test item eluted before the reference substance of lowest logKow and therefore the experimental logKow value is determined to be less than 0.3.

Key value for chemical safety assessment

Log Kow (Log Pow):

0.3

at the temperature of:

25 °C

Additional information

The experimental value of the log Kow was determined to be below 0.3. As default worst case value, 0.3 is considered for the CSA.