2,5-di-tert-butylhydroquinone

Hydrolysis

Link to relevant study record(s)

Reference

Endpoint:

hydrolysis

Type of information:

experimental study

Adequacy of study:

key study

Study period:

05 October 2019 - 22 January 2020

Reliability:

1 (reliable without restriction)

Qualifier:

according to guideline

Guideline:

OECD Guideline 111 (Hydrolysis as a Function of pH)

GLP compliance:

yes

Specific details on test material used for the study:

Test Item Name : YAPOX 2245
Chemical Name (IUPAC) : 2, 5-Di-tertiary butyl hydroquinone
EC Number : 201-841-8
CAS Number : 88-58-4
Physical Appearance : White crystalline powder
Batch No. : 20015011219
Purity (As per CoA) : 99.37%
Date of Manufacture : June 2019
Date of Retest : May 2021
Storage Condition : Ambient (21°C to 29°C)
Batch Produced by
(Name and Address) : Yasho Industries Limited
Plot No. 2514/2515, Phase IV, G.I.D.C.,
Vapi-396195, Gujarat, India.
Test Item Code by Test Facility : D819-002

Radiolabelling:

no

Analytical monitoring:

yes

Details on sampling:

A duplicate sample of each buffers pH was taken immediately after the addition of the test item on day 0 and after day 5 of incubation
The samples were prepared in duplicate for each pH 4.0, 7.0, and 9.0 buffer solutions on Day 0.
After completion of the day 5 incubation period, the sample solutions were collected and allowed to reach room temperature. The samples were prepared in duplicate for each buffers pH 4.0, 7.0, and 9.0 buffer solutions. The samples were diluted same as day 0 analysis.

Buffers:

Buffer Solution of pH 4.0: An aliquot of 410 mL of 0.2 M acetic acid solution and 90 mL of 0.2 M anhydrous sodium acetate solution were transferred into a 2000 mL volumetric flask and the volume was made up to the mark using Milli-Q water. The pH of the resulting buffer solution measured was found to be 4.1. The pH was adjusted to 4.00 by using 1.0 mL of 0.1% acetic acid solution. The final pH of the resulting buffer solution measured was found to be 4.00 and sonicated for about 5 minutes.

Buffer Solution of pH 7.0: An aliquot of 195 mL of 0.2 M monobasic sodium phosphate solution and 305 mL of 0.2 M dibasic sodium phosphate solution was transferred into a 2000 mL volumetric flask and the volume was made up to the mark using Milli-Q water. The pH of the resulting buffer solution measured was found to be 6.96. The pH was adjusted to 7.00 by using 0.6 mL of 0.1 N sodium hydroxide solution. The final pH of the resulting buffer solution measured was found to be 7.00 and sonicated for about 5 minutes.

Buffer Solution of pH 9.0: An aliquot of 1000 mL of 0.1 M boric acid solution was transferred into a 2000 mL volumetric flask and the volume was made up to the mark using Milli-Q water. The pH of the resulting solution measured was found to be 8.93. The pH was adjusted to 9.00 by using 50% w/v NaOH solution. The final pH of the resulting buffer solution measured was found to be 9.00 and sonicated for about 5 minutes.

Details on test conditions:

A preliminary test was performed at 50°C in sterile buffers of pH 4.0, 7.0 and 9.0. Test samples were analyzed for active ingredient concentration on day 0 and day 5 of post-treatment at each pH buffer solution.

Preparation of Stock Solution of Test Item
Date Particulars Weight(mg) Diluent Final Volume (mL) Conc. (mg/L) Sample ID
06/11/2019 YAPOX 2245 Sample 100.57 Acetonitrile 50 1998.73 Sample Stock

Preparation of Test Systems
Bulk homogenous solutions of test item were prepared by diluting 1.5 mL of sample stock solution to 200 mL of volumetric flask glassware using respective buffer solutions of pH 4.0, 7.0 and 9.0 respectively. The amount of co-solvent in the buffer solution was less than 1% of the final volume. The concentration of the test item in each aqueous phase did not exceed the lesser of 0.01 M in the buffer solution containing co-solvent.
The bulk solution was then be dispensed to individual pre-labeled amber colored volumetric flasks.
The test solutions were prepared aseptically under biosafety cabinet chamber as mentioned below.
Particulars Quantity Taken (mL) Diluent Final Volume (mL) Sample ID
Sample Stock 1.5 pH 4.0 Buffer 200 Sample Stock buffer pH 4.0 R1
Sample Stock 1.5 pH 4.0 Buffer 200 Sample Stock buffer pH 4.0 R2
Sample Stock 1.5 pH 7.0 Buffer 200 Sample Stock buffer pH 7.0 R1
Sample Stock 1.5 pH 7.0 Buffer 200 Sample Stock buffer pH 7.0 R2
Sample Stock 1.5 pH 9.0 Buffer 200 Sample Stock buffer pH 9.0 R1
Sample Stock 1.5 pH 9.0 Buffer 200 Sample Stock buffer pH 9.0 R2
Acetonitrile 1.5 pH 4.0 Buffer 200 Control Stock buffer pH 4.0
Acetonitrile 1.5 pH 7.0 Buffer 200 Control Stock buffer pH 7.0
Acetonitrile 1.5 pH 9.0 Buffer 200 Control Stock buffer pH 9.0

Incubation of Test Systems
The prepared solutions of the test item (at buffers pH 4.0, 7.0, and 9.0) were maintained for 5 days at 50ºC.
The solutions were analyzed for the concentration of test item on day 0 and day 5 post-treatment. After completion of 5 Days incubation period, the sample solutions were collected and allowed to reach room temperature. The samples were diluted from each pH sample stock (buffers pH 4.0, 7.0, and 9.0) in the same way as the day 0 dilutions.

Duration:

0 d

pH:

4

Temp.:

50 °C

Duration:

0 d

pH:

7

Temp.:

50 °C

Duration:

0 d

pH:

9

Temp.:

50 °C

Duration:

5 d

pH:

4

Temp.:

50 °C

Duration:

5 d

pH:

7

Temp.:

50 °C

Duration:

5 d

pH:

9

Temp.:

50 °C

Number of replicates:

A duplicate sample of each buffers pH was taken immediately after the addition of the test item on day 0 and after day 5 of incubation.

Negative controls:

yes

Preliminary study:

The test samples in pH 4.0, 7.0, and 9.0 buffer solutions were subjected to hydrolysis at 50 ± 0.5°C. Duplicate samples were analyzed along with respective control samples for test item concentration on day 0 and day 5.
Hydrolysis at pH 4.0
The test item concentration in the sterile pH 4.0 buffer samples found that 14.86 and 13.66 mg/L on day 0 and day 5 of the samples treated with the test item, respectively.
The hydrolysis of the test item after 5 days of incubation in pH 4.0 buffer solution at
50 ± 0.5ºC was 8.08% (<10% acceptance criteria).
Hydrolysis at pH 7.0
The mean test item concentration in the sterile pH 7.0 buffer samples found that 14.78 and 13.53 mg/L on day 0 and day 5 of the samples treated with the test item, respectively.
The hydrolysis of the test item after day 5 of incubation in pH 7.0 buffer solution at
50 ± 0.5ºC was 8.46% (<10% acceptance criteria).
Hydrolysis at pH 9.0
The mean test item concentration in the sterile pH 9.0 buffer samples found that 14.83 and 13.73 mg/L on day 0 and day 5 of the samples treated with the test item, respectively.
The hydrolysis of the test item after 5 days of incubation in pH 9.0 buffer solution at
50 ± 0.5ºC was 7.42% (<10% acceptance criteria).

Transformation products:

not measured

Key result

pH:

4

Temp.:

50 °C

DT50:

> 1 yr

Type:

not specified

Remarks on result:

hydrolytically stable based on preliminary test

Key result

pH:

7

Temp.:

50 °C

DT50:

> 1 yr

Type:

not specified

Remarks on result:

hydrolytically stable based on preliminary test

Key result

pH:

9

Temp.:

50 °C

DT50:

> 1 yr

Type:

not specified

Remarks on result:

hydrolytically stable based on preliminary test

Details on results:

Specificity meets an acceptance criterion for YAPOX 2245 as the interference obtained in diluent was 7.300%, Mobile phase was 1.824, diluent fortified with buffer pH 4.0 was 3.931%, diluent fortified with buffer pH 7.0 was 4.456% and diluent fortified with buffer pH 9.0 was 3.313% which are < 30% of the LOQ level.

Limit of Detection (LOD) and Limit of Quantification (LOQ)
The LOD was determined at 0.05 mg/L concentration based on S/N ≈ 2/1 and LOQ was determined at 0.10 mg/L concentration based on S/N ≥ 10/1 for YAPOX 2245.

Linearity
Linearity meets the acceptance criterion for 2,5-Di-tert-butylhydroquinone reference standard as the correlation coefficient obtained was 1.0 which is >0.99.

Accuracy (% Recovery) and Precision (% RSD)
Accuracy for YAPOX 2245 pH 4.0 meets the acceptance criterion as the % recovery obtained was 92.35% for accuracy 1 (0.50 mg/L) and 96.82% for accuracy 2 (3.01 mg/L) which are within the range 70% to 110% of the nominal concentration.
Precision meets the acceptance criterion as the % RSD for YAPOX 2245 obtained was 1.839% for accuracy 1 (0.50 mg/L) and 1.521% for accuracy 2 (3.01 mg/L) which are < 20%.
Accuracy for YAPOX 2245 pH 7.0 meets the acceptance criterion as the % recovery obtained was 93.93% for accuracy 1 (0.50 mg/L) and 97.88% for accuracy 2 (3.01 mg/L) which are within the range 70% to 110% of the nominal concentration.
Precision meets the acceptance criterion as the % RSD for YAPOX 2245 obtained was 0.987% for accuracy 1 (0.50 mg/L) and 0.713% for accuracy 2 (3.01 mg/L) which are < 20%.
Accuracy for YAPOX 2245 pH 9.0 meets the acceptance criterion as the % recovery obtained was 93.82% for accuracy 1 (0.50 mg/L) and 97.81% for accuracy 2 (3.01 mg/L) which are within the range 70% to 110% of the nominal concentration.
Precision meets the acceptance criterion as the % RSD for YAPOX 2245 obtained was 0.789% for accuracy 1 (0.50 mg/L) and 0.461% for accuracy 2 (3.01 mg/L) which are < 20%.

Sterility
Sterility was checked at experimental start (day 0) and termination (day 5) for each of the test systems (a single sample from each pH buffer solution). There was no microbial growth of total bacterial count and total yeast and mould count were observed.

pH Measurements
The mean pH values of the test samples measured on day 0 were found to be 4.0, 7.0 and 9.0 and on day 5 they were found to be 4.0, 7.0 and 9.0.

Temperature Record
The temperature of the chamber was maintained at 50 ± 0.5ºC during the preliminary test, the observed oven temperature during the 5-day incubation period was recorded as 50.0°C.

Validity criteria fulfilled:

yes

Conclusions:

On the basis of preliminary test results, the test item was hydrolyzed <10% in pH 4.0, pH 7.0 and pH 9.0 buffer solutions kept at 50 ± 0.5ºC for 5 days. The test item was considered as hydrolytically stable (t1/2 >1 Year) at buffers pH 4.0, pH 7.0 and pH 9.0.

Executive summary:

The present study was conducted to determine the hydrolytic stability of YAPOX 2245 obtained from Yasho Industries Limited,according toOECD guideline for the testing of chemicals, No. 111, Hydrolysis as a function of pH, Adopted: 13 April 2004 and United States Environmental Protection Agency, Office of Prevention, Pesticides and Toxic substances (TS-7101), Product Properties Test Guidelines OPPTS 835.2130, “Hydrolysis as a function of pH and Temperature”, EPA712-C-98-059 January 1998. The preliminary test (Tier 1) for hydrolysis of YAPOX 2245 was conducted at 50 ± 0.5°C in the dark at each of pH 4.0, 7.0 and 9.0 buffer solutions for a period of 5 days.

Based on the preliminary test data generated in this study, YAPOX 2245 was found hydrolytically stable in pH 4.0, pH 7.0 and pH 9.0 buffer solutions at 50 ± 0.5°C. The results of the preliminary study are summarized below.

1.        Analysis of pH 4.0 buffer solution on Day 5 showed 8.08% hydrolysis.

2.        Analysis of pH 7.0 buffer solution on Day 5 showed 8.46% hydrolysis.

3.        Analysis of pH 9.0 buffer solution on Day 5 showed 7.42% hydrolysis.

Results obtained in preliminary test clearly indicate that the compound YAPOX 2245 was hydrolytically stable in pH 4.0, pH 7.0 and pH 9.0 buffer solutions over a period of 5 days at 50 ± 5°C.

Description of key information

The test item was considered as hydrolytically stable (t_1/2 > 1 Year) at buffers pH 4.0, pH 7.0 and pH 9.0.

Key value for chemical safety assessment

Half-life for hydrolysis:

1 yr

at the temperature of:

50 °C

Additional information

The present study was conducted to determine the hydrolytic stability of YAPOX 2245 obtained from Yasho Industries Limited,according toOECD guideline for the testing of chemicals, No. 111, Hydrolysis as a function of pH, Adopted: 13 April 2004 and United States Environmental Protection Agency, Office of Prevention, Pesticides and Toxic substances (TS-7101), Product Properties Test Guidelines OPPTS 835.2130, “Hydrolysis as a function of pH and Temperature”, EPA712-C-98-059 January 1998.The preliminary test (Tier 1) for hydrolysis of YAPOX 2245 was conducted at 50 ± 0.5°C in the dark at each of pH 4.0, 7.0 and 9.0 buffer solutions for a period of 5 days.

Based on the preliminary test data generated in this study, YAPOX 2245 was found hydrolytically stable in pH 4.0, pH 7.0 and pH 9.0 buffer solutions at 50 ± 0.5°C. The results of the preliminary study are summarized below.

1.        Analysis of pH 4.0 buffer solution on Day 5 showed 8.08% hydrolysis.

2.        Analysis of pH 7.0 buffer solution on Day 5 showed 8.46% hydrolysis.

3.        Analysis of pH 9.0 buffer solution on Day 5 showed 7.42% hydrolysis.

Results obtained in preliminary test clearly indicate that the compound YAPOX 2245 was hydrolytically stable in pH 4.0, pH 7.0 and pH 9.0 buffer solutions over a period of 5 days at 50 ± 5°C.