2-methoxy-4-propylphenol

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

23 January - 20 October, 2015

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

The study was conducted according to an internationally recognised method, and under GLP. No deviation was reported. Test substance is adequately specified with purity. Therefore full validation applies.

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient)

Deviations:

no

Principles of method if other than guideline:

Not applicable

GLP compliance:

yes (incl. QA statement)

Remarks:

UK GLP compliance programme (inspected on 05 February 2014 / signed on 07 October 2015)

Type of method:

shake-flask method to: flask method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Key result

Type:

log Pow

Partition coefficient:

2.8

Temp.:

20 °C

pH:

3.9 - 4

Remarks on result:

other: equivalent Pow = 620

Details on results:

The detector calibration was found to be linear over the range 0 to 1.2 mg/L with a regression coefficient of 0.9993.
There were no significant interfering peaks in the chromatograms of blank control samples, whilst quantitative recovery of test substance from control samples fortified at the determined concentration levels in n-octanol and pH 4 buffer solutions was demonstrated (a mean recovery of 100% was achieved from each medium).

Table 4.7/1: Partition coefficient – results

 

Sample	A	B	C	D	E	F
n-octanol volume (mL)	10	10	15	15	20	20
Test substance in n-octanol (mg/L)	1674	1645	1675	1676	1661	1645
Total test substance in n-octanol (µg)	16700	16500	25100	25100	33200	32900
Aqueous volume (mL)	20	20	15	15	10	10
Test substance in aqueous phase (mg/L)	4.043	2.452	2.503	2.463	2.474	2.481
Total test substance in aqueous phase (µg)	80.9	49.0	37.5	36.9	24.7	24.8
Total test substance added (µg)	16700	16700	25100	25100	33500	33500
Total test substance recovered (µg)	16800	16500	25200	25200	33200	32900
Mass balance (%)	101	99	100	100	99	98
pH of aqueous phase after partition	4.0	4.0	4.0	4.0	4.0	3.9
Pow	414	671	669	680	671	663
log10Pow	2.62	2.83	2.83	2.83	2.83	2.82

 

Mean log₁₀P_ow= 2.79 ± 0.09

Equivalent P_ow= 621

Conclusions:

The substance has low potential to bioaccumulate in the environment, according to CLP classification criteria for aquatic chronic toxicity (log10Pow<4).

Executive summary:

The partition coefficient of the test substance was measured under GLP according to the OECD 107/EU A8 guideline, flask method. Experiments were conducted with different octanol/water ratio, with buffer at pH 4, and the mean result was retained.

Test substance was determined to have a log₁₀P_ow value of 2.8 (equivalent P_ow= 620) at 20°C and pH 4.

Description of key information

The data is relevant for classification in aquatic chronic toxicity hazard class, according to CLP criteria. The substance has LOW potential for bioaccumulation (log Kow<4). 

Key value for chemical safety assessment

Log Kow (Log Pow):

2.8

at the temperature of:

20 °C

Additional information

A fully reliable GLP experimental study, conducted according to a recognized OECD/EU method, is available. It is considered as a key study. The result is retained as key data.