Reaction product of 3,5,5-trimethyl-hexanoic acid and 2-methylpropanoic acid and pentaerythritol

Adsorption / desorption

Link to relevant study record(s)

Reference

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

key study

Study period:

15 July 2011 - 09 February 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Study conducted in accordance with International guidelines and in accordance with GLP. All guideline validity criteria were met.

Qualifier:

according to guideline

Guideline:

OECD Guideline 121 (Estimation of the Adsorption Coefficient (Koc) on Soil and on Sewage Sludge using High Performance Liquid Chromatography (HPLC))

Version / remarks:

22 Jan 2001

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.19 (Estimation of the Adsorption Coefficient (KOC) on Soil and Sewage Sludge Using High Performance Liquid Chromatography (HPLC))

Version / remarks:

Commission Regulation (EC) No 440/2008 laying down test methods pursuant to Regulation (EC) No 1907/2006 of the European Parliament and of the Council on the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH).

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC estimation method

Specific details on test material used for the study:

RADIOLABELLING INFORMATION (if applicable)
- Radiochemical purity: N/A
- Specific activity: N/A
- Locations of the label: N/A
- Expiration date of radiochemical substance: N/A

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Room temperature in the dark and under nitrogen.
- Stability under test conditions: Assumed stable.
- Solubility and stability of the test substance in the solvent/vehicle: N/A, applied as supplied.
- Reactivity of the test substance with the solvent/vehicle of the cell culture medium: N/A

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: N/A
- Preliminary purification step (if any): N/A
- Final dilution of a dissolved solid, stock liquid or gel: N/A
- Final preparation of a solid: N/A

FORM AS APPLIED IN THE TEST (if different from that of starting material): Applied as supplied.

TYPE OF BIOCIDE/PESTICIDE FORMULATION (if applicable): N/A

OTHER SPECIFICS: No

Radiolabelling:

no

Details on study design: HPLC method:

EQUIPMENT
- Apparatus: Agilent 1200 Series LC
- Column: HyperClone CPS (25 cm x 4.6 mm)
- Column temperature: 25 ºC
- Flow rate: 1 mL/min
- Detection system: UV set at 210 nm

MOBILE PHASES
- Type: Acetonitrile: water (55:45 v/v)
- Experiments with additives carried out on separate columns: no
- pH: Not adjusted
- Solutes for dissolving test and reference substances: Test item dissolved in mobile phase.

DETERMINATION OF DEAD TIME
- Method: measurement of an internal deadtime standard (IDS), formamide, which has no retention time on the HPLC column.

REFERENCE SUBSTANCES
- Identity: Acetanilide, nitrobenzene, naphthalene, 2-methylnaphthalene, anthracene and DDT.

DETERMINATION OF RETENTION TIMES
- Quantity of test substance introduced in the column: 20 µL of a solution prepared at 1440 mg/L.
- Quantity of reference substances: 20 µL of each of the following solutions; acetanilide (11 mg/L); nitrobenzene (11.1 mg/L); naphthalene (4.67 mg/L); 2-methylnaphthalene (5.24 mg/L); anthracene (9.60 mg/L); DDT (10.6 mg/L).
- Intervals of calibration: Before and after analysis of tet item.

REPETITIONS
- Number of determinations: 2

EVALUATION
- Calculation of capacity factors k': k = (Tr-T0) / T0 where; Tr = retention time of sample/ standard and T0 = retention time of IDS
- Calculation of retention times: Retention time of standard/ sample - retention time of IDS
- Determination of the log Koc value: A calibration plot of log10k versus log10Koc was constructed for the reference standards. The logarithms of the capacity factors for the test substance were then calculated and log10Koc values determined by interpolation.

Key result

Sample No.:

#1

Type:

log Koc

Value:

>= 4 dimensionless

Remarks on result:

other: N/A

Details on results (HPLC method):

See Table 1

Table 1       HPLC determination of log₁₀K_oc for Tetraesters of pentaerythritol with 2- methylpropanoic acid and 3,5,5-trimethyl-hexanoic acid

 

Sample	Component	Retention time (tr) (mins)	k	log10k	log10Koc
Standard mix run A (t0= 2.909 mins)	Acetanilide	3.369	0.158	-0.801	1.3
	Nitrobenzene	3.881	0.334	-0.476	2.4
	Naphthalene	4.368	0.502	-0.300	2.8
	2-methylnaphthalene	4.575	0.573	-0.242	3.9
	Anthracene	4.984	0.713	-0.147	4.4
	DDT	6.697	1.302	0.115	5.6
Sample A (t0= 2.910 mins)	Test Item	4.808 6.191	0.652 1.127	-0.186 0.052	4.0 5.2
Sample B (t0= 2.907 mins)	Test Item	4.806 6.190	0.653 1.129	-0.185 0.053	4.0 5.2
Standard mix run B (t0= 2.912 mins)	Acetanilide	3.374	0.159	-0.800	1.3
	Nitrobenzene	3.886	0.334	-0.476	2.4
	Naphthalene	4.374	0.502	-0.299	2.8
	2-methylnaphthalene	4.581	0.573	-0.242	3.9
	Anthracene	4.990	0.714	-0.147	4.4
	DDT	6.706	1.303	0.115	5.6

Linear regression (based on std. mix run A & B): log₁₀K_oc= 4.93 log₁₀k + 4.90

Validity criteria fulfilled:

yes

Conclusions:

The components of Tetraesters of pentaerythritol with 2-methylpropanoic acid and 3,5,5-trimethyl-hexanoic acid were found to have log10 Koc values of greater than or equal to 4.0 (equivalent Koc ≥ 10000).

Executive summary:

OECD 121 (2012) - The sorption behaviour of the test substance on soil was investigated using high performance liquid chromatography (HPLC).

The adsorption coefficient was deduced from the capacity factor (k) given by:

 

k = (t_r– t₀) / t₀

 

where;

t_r was the measured retention time of sample or reference standard

t₀ was the retention time of the internal deadtime standard (formamide). 

 

In order to correlate the measured capacity factor (k) of the test material with its K_oc, six reference materials were selected from a list of recommended compounds. These reference compounds were selected to have log₁₀ K_oc values between 1.3 and 5.6. An internal standard (formamide) with no retention on the HPLC column was used to determine the deadtime of the HPLC system. 

 

A solution of Tetraesters of pentaerythritol with 2-methylpropanoic acid and 3,5,5-trimethyl-hexanoic acid (1440 mg/l in HPLC mobile phase (acetonitrile:water 55:45 v/v), and also containing I.D.S. at the same concentration as in the reference mixture) was prepared and chromatographed in duplicate, bracketed by samples of the reference mixture, using HPLC.

 

A calibration plot of log₁₀k versus log₁₀ K_oc was constructed for the reference standards. The logarithms of the capacity factors for the test substance were then calculated and log₁₀ K_oc values determined by interpolation, if appropriate.

 

Two of the components of Tetraesters of pentaerythritol with 2-methylpropanoic acid and 3,5,5-trimethyl-hexanoic acid had retention times within the range of the reference standards and were determined to have log₁₀ K_oc values of 4.0 and 5.2. The other components had a retention time greater than DDT, indicating log₁₀ K_oc values of greater than 5.6.

  

In summary, the components of Tetraesters of pentaerythritol with 2-methylpropanoic acid and 3,5,5-trimethyl-hexanoic acid were found to have log₁₀ K_oc values of greater than or equal to 4.0 (equivalent K_oc ≥ 10000).

 

 

Description of key information

Adsorption/ desorption = logK_oc: ≥4.0 (equivalent K_oc ≥10000); OECD 121; Sydney, P. (2012)

Additional information

OECD 121 (2012) - The sorption behaviour of the test substance on soil was investigated using high performance liquid chromatography (HPLC).

The adsorption coefficient was deduced from the capacity factor (k) given by:

 

k = (t_r– t₀) / t₀

 

where;

t_r was the measured retention time of sample or reference standard

t₀ was the retention time of the internal deadtime standard (formamide). 

 

In order to correlate the measured capacity factor (k) of the test material with its K_oc, six reference materials were selected from a list of recommended compounds. These reference compounds were selected to have log₁₀K_ocvalues between 1.3 and 5.6. An internal standard (formamide) with no retention on the HPLC column was used to determine the deadtime of the HPLC system. 

 

A solution of Tetraesters of pentaerythritol with 2- methylpropanoic acid and 3,5,5-trimethyl-hexanoic acid (1440 mg/l in HPLC mobile phase (acetonitrile:water 55:45 v/v), and also containing I.D.S. at the same concentration as in the reference mixture) was prepared and chromatographed in duplicate, bracketed by samples of the reference mixture, using HPLC.

 

A calibration plot of log₁₀k versus log₁₀K_ocwas constructed for the reference standards. The logarithms of the capacity factors for the test substance were then calculated and log₁₀K_ocvalues determined by interpolation, if appropriate.

 

Two of the components of Tetraesters of pentaerythritol with 2- methylpropanoic acid and 3,5,5-trimethyl-hexanoic acid had retention times within the range of the reference standards and were determined to have log₁₀K_ocvalues of 4.0 and 5.2. The other components had a retention time greater than DDT, indicating log₁₀K_ocvalues of greater than 5.6.

  

In summary, the components of Tetraesters of pentaerythritol with 2- methylpropanoic acid and 3,5,5-trimethyl-hexanoic acid were found to have log₁₀K_ocvalues of greater than or equal to 4.0 (equivalent K_oc ≥ 10000).