2-tert-butyl-1,4-dimethoxybenzene

Hydrolysis

Link to relevant study record(s)

Reference

Endpoint:

hydrolysis

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2019-04-25 to 2019-05-01

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 111 (Hydrolysis as a Function of pH)

Version / remarks:

OECD Guideline for the Testing of Chemicals – 111 Hydrolysis as a Function of pH

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Test Item Name: Vetimoss
Chemical Name: 2-tert-butyl-1,4-dimethoxybenzene
Batch/Lot Number: A180118C
CAS Number: 21112-37-8
Appearance: Clear, pale yellow liquid
Expiry Date: 06 June 2019
Purity: 98 %
Storage condition: Protected from humidity (tight closed container) and under inert gas

Radiolabelling:

no

Analytical monitoring:

yes

Details on sampling:

- Test vessels: 10 – 10 tubes with Test Media (at all pH levels) were spiked with the Spiking Stock Solution. 5 of them were processed immediately to determine the initial concentration of the test item and the other 5 tubes were incubated at 50°C for 5 days and, after the incubation period, all the tubes were processed and measured.
- Control: 4 – 4 control tubes were also prepared (Test Media without spiking) to check the potential interfering components from the buffer. 2 of them were processed immediately to determine the initial concentrations of the test item and the other 2 tubes were incubated at 50°C for 5 days and, after the incubation period, both control tubes were processed and measured.

Details on test conditions:

SOLUTIONS, MIXTURES
- Diluent: n-Heptane was used as Diluent.
- Extraction Solvent: n-Heptane was used as Extraction Solvent.
- Test Media: Aqueous buffers at pH 4, 7 and 9 were used as Test Media.
- Stock Solution of Test Item: Approx. 15 mg Test Item was weighed with 0.01 mg precision into 10 mL volumetric flask and filled up with Diluent. The solution was mixed well by hand. The concentration of the test item was approx. 1.5 mg/mL.
- Working Solution: The Stock Solution of Test Item was diluted to 0.1 mg/mL with Diluent.
- Stock Solution of Internal Standard: Approx. 15 mg Internal Standard was weighted with 0.01 mg precision into 5 mL volumetric flask and filled up with Diluent. The solution was mixed well by hand. The concentrations of the test item was approx. 3 mg/mL.
- Calibration Solutions: The Stock Solution of Test Item and the Working Solution were diluted to the 0.01 – 0.15 mg/L range and constant amount of Stock Solution of Internal Standard was added. Calibration solutions were injected in duplicate.
- Spiking Stock Solution: Approx. 50 mg Test Item was weighted with 0.01 mg precision into 5 mL volumetric flask and filled up with Tetrahydrofuran. The solution was mixed well by hand. The concentration of the test item was approx. 10 mg/mL.
- Preparation of Test Solutions: 50 mL Test Media was spiked with 50 µL Spiking Stock Solution and mixed well by hand.
- Analytical Sample Preparation: 50 mL aliquot of Test Solution was extracted with 1 mL Extraction Solvent (50x enhancement). 100 µL extract was mixed with 50 µL Stock Solution of Internal Standard and 850 µL Diluent.

- Temperature: The Test Solutions were kept between 50.1 – 50.4°C.

Duration:

5 d

pH:

4

Temp.:

50 °C

Initial conc. measured:

10.408 mg/L

Duration:

5 d

pH:

7

Temp.:

50 °C

Initial conc. measured:

10.744 mg/L

Duration:

5 d

pH:

9

Temp.:

50 °C

Initial conc. measured:

10.789 mg/L

Number of replicates:

10 – 10 tubes with Test Media (at all pH levels) were spiked with the Spiking Stock Solution.

Positive controls:

no

Negative controls:

yes

Remarks:

4 – 4 control tubes of test media without spiking

Preliminary study:

The Vetimoss test item is hydrolytcally stable in pH 4 – 9 range, with recoveries of 95.1-99.6% after 5 days at 50°C.

Transformation products:

not measured

% Recovery:

99.3

pH:

4

Temp.:

50 °C

Duration:

5 d

% Recovery:

99.6

pH:

7

Temp.:

50 °C

Duration:

5 d

% Recovery:

95.1

pH:

9

Temp.:

50 °C

Duration:

5 d

pH:

4

Temp.:

50 °C

Type:

not specified

Remarks on result:

hydrolytically stable based on preliminary test

pH:

7

Temp.:

50 °C

Type:

not specified

Remarks on result:

hydrolytically stable based on preliminary test

pH:

9

Temp.:

50 °C

Type:

not specified

Remarks on result:

hydrolytically stable based on preliminary test

Details on results:

The Vetimoss is hydrolytically stable at 50°C.

Stability of the test item after 5 days

pH	cTestSol (mg/L)		Stability (%)
	Day-0	Day-5
4	10.408	10.332	99.3
7	10.744	10.704	99.6
9	10.789	10.263	95.1

Measured initial concentrations

Sample	cTheroretical (mg/L)	pH	cTestSol (mg/L)	cAverage (mg/L)	% of cTheor	RSD (%)
191-HYD-001	0	4	<LOQ	<LOQ	N/A	N/A
191-HYD-002	0	4	<LOQ
191-HYD-003	10.070	4	10.619	10.408	103.4	2.5
191-HYD-004	10.070	4	10.080
191-HYD-005	10.070	4	10.378
191-HYD-006	10.070	4	10.247
191-HYD-007	10.070	4	10.717
191-HYD-008	0	7	<LOQ	<LOQ	N/A	N/A
191-HYD-009	0	7	<LOQ
191-HYD-010	10.070	7	10.662	10.744	106.7	1.1
191-HYD-011	10.070	7	10.741
191-HYD-012	10.070	7	10.616
191-HYD-013	10.070	7	10.789
191-HYD-014	10.070	7	10.914
191-HYD-015	0	9	<LOQ	<LOQ	N/A	N/A
191-HYD-016	0	9	<LOQ
191-HYD-017	10.070	9	10.746	10.789	107.1	1.3
191-HYD-018	10.070	9	10.858
191-HYD-019	10.070	9	10.594
191-HYD-020	10.070	9	10.982
191-HYD-021	10.070	9	10.767

Measured concentrations after 5 days

Sample	cTheroretical (mg/L)	pH	cTestSol (mg/L)	cAverage (mg/L)	% of cTheor	RSD (%)
191-HYD-022	0	4	<LOQ	<LOQ	N/A	N/A
191-HYD-023	0	4	<LOQ
191-HYD-024	10.070	4	10.597	10.332	102.6	6.3
191-HYD-025	10.070	4	10.531
191-HYD-026	10.070	4	10.670
191-HYD-027	10.070	4	10.693
191-HYD-028	10.070	4	9.167
191-HYD-029	0	7	<LOQ	<LOQ	N/A	N/A
191-HYD-030	0	7	<LOQ
191-HYD-031	10.070	7	10.749	10.704	106.3	0.6
191-HYD-032	10.070	7	10.740
191-HYD-033	10.070	7	10.585
191-HYD-034	10.070	7	10.713
191-HYD-035	10.070	7	10.733
191-HYD-036	0	9	<LOQ	<LOQ	N/A	N/A
191-HYD-037	0	9	<LOQ
191-HYD-038	10.070	9	10.879	10.263	101.9	5.9
191-HYD-039	10.070	9	10.260
191-HYD-040	10.070	9	10.333
191-HYD-041	10.070	9	10.582
191-HYD-042	10.070	9	9.262

Validity criteria fulfilled:

yes

Conclusions:

Vetimoss is hydrolytically stable at 50°C.

Executive summary:

The potential for Vetimoss to hydrolyse at 3 different pHs was examined in a study undertaken in accordance with OECD 111. Vetimoss is hydrolytically stable at pH 4, 7 and 9 at 50°C.

Description of key information

The potential for Vetimoss to hydrolyse at 3 different pHs was examined in a study undertaken in accordance with OECD 111. Vetimoss is hydrolytically stable at pH 4, 7 and 9 at 50°C.