Semicarbazide hydrochloride

Hydrolysis

Link to relevant study record(s)

Reference

Endpoint:

hydrolysis

Type of information:

experimental study

Adequacy of study:

key study

Study period:

26 November 2017 - 24 August 2018

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)

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: 55507861
- Expiration date of the lot/batch: 28 April 2019

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Room temperature (15 to 25°C), dark

Analytical monitoring:

yes

Details on sampling:

The samples, of nominal concentration 1 g/L, were incubated at 50°C in the dark until sampling was required (immediately, and then after 2.4, 70 (pH 4 and pH 7 only) and
120 hours).

At each sampling time, two samples were removed from the bath and an aliquot (100 μL) of each was diluted to volume (20 mL) with methanol. A portion (1 mL) of the resultant solution was then diluted to 10 mL with methanol for analysis by liquid chromatography-mass spectrometry (LC-MS).

Sample pH and incubation temperature were monitored over the period of the test.

Buffers:

Buffer solutions were prepared as follows:
pH 4: 0.2M aqueous potassium dihydrogen orthophosphate (220 mL) was mixed with
0.07M aqueous disodium hydrogen orthophosphate dodecahydrate (500 mL) and purified water (1280 mL). The pH was adjusted to 4.0 ± 0.05 with orthophosphoric acid.

pH 7:0.2M aqueous potassium dihydrogen orthophosphate (500 mL) was mixed with
1M sodium hydroxide (60 mL) and purified water (1440 mL). The pH was adjusted to
7.0 ± 0.05 with 1M hydrochloric acid or 1M sodium hydroxide, as required.

pH 9: 0.2M aqueous tris(hydroxymethyl)aminomethane (100 mL) was mixed with
0.2M hydrochloric acid (10 mL) and purified water (290 mL). The pH was adjusted to
9.0 ± 0.05 with 1M hydrochloric acid.

Details on test conditions:

Tests were carried out using reagent grade chemicals, purified sterile water and sterilised glassware.

Duration:

5 d

pH:

4

Temp.:

50 °C

Initial conc. measured:

>= 1 254 - <= 1 311 mg/L

Duration:

5 d

pH:

7

Temp.:

50 °C

Initial conc. measured:

>= 1 135 - <= 1 200

Duration:

5 d

pH:

9

Temp.:

50 °C

Initial conc. measured:

>= 1 069 - <= 1 100

Number of replicates:

2

Positive controls:

no

Negative controls:

no

Preliminary study:

The preliminary study showed that at each of pH 4, 7 and 9 and 50 ± 0.5ºC, less than 10% hydrolysis had occurred after 120 hours (5 days), equivalent to a half-life of greater than
1 year under environmental conditions (25°C). No further testing was considered necessary.

Transformation products:

no

% Recovery:

> 90

pH:

4

Temp.:

50 °C

Duration:

5 d

% Recovery:

> 90

pH:

7

Temp.:

50 °C

Duration:

5 d

% Recovery:

> 90

pH:

9

Temp.:

50 °C

Duration:

5 d

Remarks on result:

hydrolytically stable based on preliminary test

Details on results:

The preliminary study showed that at each of pH 4, 7 and 9 and 50  0.5ºC, less than 10% hydrolysis had occurred after 120 hours (5 days), equivalent to a half-life of greater than
1 year under environmental conditions (25°C). No further testing was considered necessary.

Validity criteria fulfilled:

yes

Conclusions:

Semicarbazide Hydrochloride was determined to be hydrolytically stable under acidic, neutral and basic conditions.

Description of key information

Semicarbazide Hydrochloridewas determined to be hydrolytically stable under acidic, neutral and basic conditions.

Key value for chemical safety assessment

Half-life for hydrolysis:

1 yr

at the temperature of:

25 °C

Additional information

The half-life of greater than 1 year under environmental conditions (25°C). Value of 1 year is used for the risk assessment.