Reaction mass of 2-dodecylhexadecyl methacrylate and 2-Tetradecyloctadecyl methacrylate

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:

30 April 2019 - 07 June 2019

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

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))

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))

Deviations:

no

GLP compliance:

no

Remarks:

Study performed as part of suite of non-GLP studies (predominantly Phys Chem). Although not GLP the work was performed following good scientific practices and adhered to the study plan and subsequent amendments as such .

Type of method:

HPLC estimation method

Specific details on test material used for the study:

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Room temperature in the dark

Radiolabelling:

no

Test temperature:

Column temperature: 30 °C

Details on study design: HPLC method:

EQUIPMENT
- Apparatus: HPLC
- Type:variable wavelength (VW),evaporative light scattering (ELS)
- Type, material and dimension of analytical column: XSelect HSS Cyano 5 µ (150 x 4.6 mm id)
- Detection system: Agilent Technologies 1200

MOBILE PHASES
- Type: Isocratic methanol:purified water (55:45 v/v)
- Experiments with additives carried out on separate columns: no
- pH: 5.7
- Solutes for dissolving test and reference substances: propan-2-ol and methanol respectively

DETERMINATION OF DEAD TIME
- Method: The dead time was determined by measuring the retention time of formamide (purity* 99.6%) of a 709 mg/L solution in mobile phase.

REFERENCE SUBSTANCES
- Identity: Acetanilide(Purity: 99%),Phenol(Purity: 99%),Atrazine(Purity: 99%),Isoproturon (Purity: >98%),Triadimenol(Purity: 97.8%), Linuron (Purity: 99.7%),Naphthalene(Purity: 99%),Endosulfan-diol(Purity: 99.9%)Fenthion(Purity: 98.6% α-Endosulfan(Purity: 99.8%),Phenanthrene(Purity:≥99.5%),Diclofop-methyl(Purity:99.8%),DDT(Purity:98.7%).

DETERMINATION OF RETENTION TIMES
- Quantity of test substance introduced in the column:5 µL
- Quantity of reference substances:5 µL
- Intervals of calibration: Not addressed

REPETITIONS
- Number of determinations: 2

EVALUATION
- Calculation of capacity factors k': The capacity factor for each reference standard was calculated using the following equation: k'= tr - t0 ÷ t0 where: k' = capacity factor tr = retention time (min) t0 = dead time retention time (min).
- Calculation of retention times: A correlation of log10 k' versus log10 Koc of the reference standards was plotted using linear regression.The capacity factors (k') for the reference standards were calculated using the previous equation. Log10 Koc values are those quoted in Method 121 of the OECD Guidelines for Testing of Chemicals, 22 January 2001.
- Determination of the log Koc value: Initially the capacity factor of the test item was calculated using the "calculation of capacity facors k'" equation mentioned above. The adsorption coefficient was then calculated using the following equation with reference to the calibration curve. log10 Koc= log10 k'-A÷B Where: Koc = adsorption coefficient, k'= capacity factor, A= intercept of the calibration curve, B= slope of calibration curve.

Details on sampling:

N/A

Details on matrix:

N/A

Details on test conditions:

N/A

Computational methods:

N/A

Sample No.:

#1

Type:

log Koc

Value:

> 5.63 dimensionless

pH:

5.7

Temp.:

30 °C

Sample No.:

#2

Type:

log Koc

Value:

> 5.63 dimensionless

pH:

5.7

Temp.:

30 °C

Key result

Type:

Koc

Value:

> 427 000 dimensionless

pH:

5.7

Temp.:

30 °C

Details on results (HPLC method):

- Retention times of reference substances used for calibration (Mean Retention Time (min)): Acetanilide 2.684,Phenol 2.570,Atrazine 3.695,Isoproturon 3.942,Triadimenol 5.289,Linuron 5.420,Naphthalene 4.691,Endosulfan-diol 6.724,Fenthion 7.995,α-Endosulfan 11.336, Diclofop-methyl 12.225,Phenanthrene 8.709,DDT 23.913.
- Details of fitted regression line (log k' vs. log Koc): y = 0.334x -0.7149, R² = 0.9314
- Graph of regression line attached
- Average retention data for test substance: Retention time: ≥35.939 (min)

Validity criteria fulfilled:

not applicable

Conclusions:

The adsorption coefficient of Reaction Mass of 2-Propenoic acid, 2-methyl-, 2-dodecylhexadecyl ester and 2-Propenoic acid, 2-methyl-, 2-tetradecyloctadecyl ester has been determined to be greater than 4.27 x 10^5, log10 Koc >5.63 at 30°C.

Executive summary:

The adsorption coefficient of Reaction Mass of 2-propenoic acid, 2-methyl-,2 dodecylhexadecyl ester and 2-propenoic acid, 2methyl-,2-tetradecyloctadecyl ester was determined using the HPLC method, designed to be compatible with Method C.19 Adsorption Coefficient of Commission Regulation (EC) No 440/2008 of 30 May 2008 and Method 121 of the OECD Guidelines for Testing of Chemicals, 22 January 2001.The test system utilized a high-performance liquid chromatograph. A commercially available cyanopropyl reverse phase HPLC column containing lipophilic and polar moieties was used. The dead time was determined by measuring the retention time of formamide (purity>99%) at 709 mg/L solution in mobile phase. Solutions of reference standards were prepared in methanol. An aliquot of test item (0.5007 g) was diluted to 100 mL with propan-2-ol to give a concentration of 5.01 x 103 mg/L. The sample dead time and reference standard solutions were injected in duplicate into the HPLC. The mobile phase was ramped to 100% propan-2-ol shortly after the elution of the last reference standard in order to elute any highly retained test item components. This was carried out for the sample and sample blank injections only. The capacity factor for each reference standard was calculated. A correlation of log10 k' versus log10 Koc of the reference standards was plotted using linear regression. Log10 Koc values were those quoted in Method 121 of the OECD Guidelines for Testing of Chemicals, 22 January 2001.Initially the capacity factor of the test item was calculated. The adsorption coefficient was then calculated with reference to the calibration curve. The retention time, capacity factor(k'), Log10 k' and log10 Koc values determined for the samples were as follows. Injection 1: retention time= ≥35.939, Capacity factor (k’) = >11.214, Log10K’= >1.05 and Log10Koc = >5.63. Injection 2: retention time= ≥35.934, Capacity factor (k’) = >11.214, Log10K’= >1.05 and Log10Koc=>5.63. The Overall log10 Koc= 5.63, overall adsorption coefficient= >4.27 x 105. The adsorption coefficient of Reaction Mass of 2-propenoic acid, 2-methyl-, 2 dodecylhexadecyl ester and 2-propenoic acid, 2methyl-, 2-tetradecyloctadecyl ester was determined to be greater than 4.27 x 10^5, log10 Koc >5.63.

Description of key information

The adsorption coefficient of Reaction Mass of 2-propenoic acid, 2-methyl-, 2 dodecylhexadecyl ester and 2-propenoic acid, 2methyl-, 2-tetradecyloctadecyl ester was determined to be greater than 4.27 x 10^5, log10 Koc >5.63.

Key value for chemical safety assessment

Other adsorption coefficients

Type:

other: log10 Koc >5.63

at the temperature of:

30 °C

Additional information

The adsorption coefficient of Reaction Mass of 2-propenoic acid, 2-methyl-, 2 dodecylhexadecyl ester and 2-propenoic acid, 2methyl-, 2-tetradecyloctadecyl ester was determined using the HPLC method, designed to be compatible with Method C.19 Adsorption Coefficient of Commission Regulation (EC) No 440/2008 of 30 May 2008 and Method 121 of the OECD Guidelines for Testing of Chemicals, 22 January 2001. The test system utilized a high-performance liquid chromatograph. A commercially available cyanopropyl reverse phase HPLC column containing lipophilic and polar moieties was used. The dead time was determined by measuring the retention time of formamide (purity>99%) at 709 mg/L solution in mobile phase. Solutions of reference standards were prepared in methanol. An aliquot of test item (0.5007 g) was diluted to 100 mL with propan-2-ol to give a concentration of 5.01 x 103 mg/L. The sample, dead time and reference standard solutions were injected in duplicate into the HPLC. The capacity factor for each reference standard was calculated. A correlation of log10 k' versus log10 Koc of the reference standards was plotted using linear regression. Log10 Koc values were those quoted in Method 121 of the OECD Guidelines for Testing of Chemicals, 22 January 2001. Initially the capacity factor of the test item was calculated. The adsorption coefficient was then calculated with reference to the calibration curve. The retention time, capacity factor and log10 Koc values determined for the samples were identical. Injections 1&2: retention time= ≥35.939, Capacity factor (k’) = >11.214, Log10K’= >1.05 and Log10Koc=>5.63. The Overall log10 Koc= 5.63, overall adsorption coefficient= >4.27 x 105. The adsorption coefficient of Reaction Mass of 2-propenoic acid, 2-methyl-, 2 dodecylhexadecyl ester and 2-propenoic acid, 2methyl-, 2-tetradecyloctadecyl ester was determined to be greater than 4.27 x 10^5, log10 Koc >5.63.