Amines, C12-14-alkyl, C6-10-alkyl phosphates

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 107 (Partition Coefficient (n-octanol / water), Shake Flask Method)

Deviations:

not specified

GLP compliance:

yes

Type of method:

flask method

Partition coefficient type:

octanol-water

Analytical method:

other: LC-MS

Key result

Type:

log Pow

Partition coefficient:

> 2.47

Temp.:

22 °C

pH:

ca. 4

Remarks on result:

other: UVCB

Remarks:

As shown above one component is hydrophilic having a log Kow value of 0.58, whereas the remaining constituents da show higher log Kow values; given the difficulties of determining accurate water solubility values of individual components of this UVCB substance due to sensitivity limitations, the accuracy of log Kow values as reported above is limited.

Details on results:

LC-MS area% assessment indicated three components >10% in the test substance Deophos 228, lntertek Reference 10568367, plus dodecylamine which could not be included in area% valuation due to different ionisation properties.

Conclusion - Dodecvlamine

A Log P value of >2.36 was obtained, the ">" value was used because the water layers

were reported as <2 mg/L. The actual value, which may be significantly lower, could not be

determined as the values in the water solutions were similar or lower than the value in the

water blank.

The recoveries for dodecylamine test solution vary between 58% and 104%. This suggests

due to the Iew recovery in water, that there may be Iosses in the octanollayer. But it should

be noted that the recovery value is dependent on an accurate area% value, and variations

will be inherent in this value as a nominal value from a similar batch has been used.

The stock solution recovery values are similar to those obtained for the test solutions,

indicating no significant evidence of degradation during testing.

Reporting of the Log P value as a ">" value does cover a possible increase in the Log P

value due to Iosses from octanol but considerations should also be given to the impact of

variation in the dodecylamine content used which was not specific to the test substance.

Both factors will impact the accuracy of the Log P value reported although the individual

values obtained are within the ±0.3 Log units considered appropriate for this test.

Conclusion - Bis(2-ethylhexyl) Phosphate

A Log P value of >2.47 was obtained, the ">" value was used beGause the water layers

were reported as <1 mg/L. The aGtual value, whiGh may be signifiGantly lower, could not be

determined as the values in the water solutions were similar or lower than the value in the

water blank.

The recoveries for bis(2-ethylhexyl) phosphate test solutions vary between 36% and 42%,

suggesting Iosses in the octanol layer. But it should be noted that the recovery value is

dependent on an accurate area% value, and variation may be inherent in the values due to

the differences in ionisation for each component and that not all components may be

observed by LC-MS.

The stock solution recovery values for bis(2-ethylhexyl) phosphate are similar to those

obtained for the test solutions, indicating no significant evidence of degradation du ring

testing.

Reporting of the Log P value as a ">" value does cover a possible increase in the Log P

value due to Iosses from octanol but considerations should also be given to the impact of

variation in the bis(2-ethylhexyl) phosphate content used which was not specific to the test

substance. 8oth factors will impact the accuracy of the Log P value reported. The individual

values obtained are slightly outside the ±0.3 Log units considered appropriate for this test

(maximum difference is 0.35) but this is impacted by the use of "<" values and is not

considered significant.

Conclusion - 2-Ethylhexyl Phosphate

A Log P value of 0.58 was obtained.

The recoveries for 2-ethylhexyl phosphate test solutions varied between 144% and 322%.

This varies from the other related components in that no Iosses are evident, but overestimation

does appear to occur. Again it is noted that recovery is dependent on an

accurate area% value as discussed previously.

The stock solution recoveries for 2-ethylhexyl phosphate are similar to those obtained for

the test solutions, i.e. they are higher than expected, although the magnitude is not as great.

Given the variation obtained during the analysis, this is regarded as an indication of no

significant evident of degradation during testing.

The individual values obtained are within the ±0.3 Log units considered to be appropriate for

this test.

Conclusion - 2-Ethylhexyl Hexyl Phosphate

A Log P value of > 1. 78 was obtained, the ">" value was used because the water layers

were reported as <1 mg/L. The actual value, which may be significantly lower, could not be

determined as the values in the water solutions were similar or lower than the value in the

water blank.

The recoveries for 2-ethylhexyl hexyl phosphate test solutions vary between 40% and 50%,

suggesting Iosses in the octanol layer. But it should be noted that the recovery value is

dependent on an accurate area% value, and variation may be inherent in the values due to

the differences in ionisation for each component and that not all components may be

observed by LC-MS.

The stock solution recovery values for 2-ethylhexyl hexyl phosphate are similar to those

obtained for the test solutions, indicating no significant evidence of degradation during

testing.

Reporting of the Log P value as a ">" value does cover a possible increase in the Log P

value due to Iosses from octanol but considerations should also be given to the impact of

variation in the 2-ethylhexyl hexyl phosphate content used which was not specific to the test

substance. 8oth factors will impact the accuracy of the Log P value reported. The individual

values obtained are slightly outside the ±0.3 Log units considered appropriate for this test

(maximum difference is 0.42) but this is impacted by the use of "<" values and is not

considered significant.

Conclusions:

As shown above one component is hydrophilic having a log Kow value of 0.58, whereas the
remaining constituents da show higher log Kow values; given the difficulties of determining accurate
water solubility values of individual components of this UVCB substance due to sensitivity
limitations, the accuracy of log Kow values as reported above is limited.

Executive summary:

Analyte                                   Log Kow  Value

dodecylamine                            >2.36

bis(2-ethylhexyl) phosphate       >2.47

2-ethylhexyl phosphate               0.58

2-ethylhexyl hexyl phosphate       >1 .78

As shown above one component is hydrophilic having a log Kow value of 0.58, whereas the

remaining constituents da show higher log Kow values; given the difficulties of determining accurate

water solubility values of individual components of this UVCB substance due to sensitivity

limitations, the accuracy of log Kow values as reported above is limited.

Description of key information

The partition coefficient was determined according to OECD Guideline 107.

Key value for chemical safety assessment

Log Kow (Log Pow):

2.47

at the temperature of:

22 °C

Additional information

The log Kow values of individual constituents are reported as: >2.36 (dodecylamine), >2.47 bis-(2 -ethylhexyl) phosphate, 0.58 () and >1.78 (2 -ethylhexyl hexyl phosphate). However for the prupose of CSA, the highest value is taken forward. Due to the difficulties of determining accurate water solubility values of individual components of this UVCB substance due to sensitivity limitations, the accuracy of log Kow values is limited.