3-acetylthiazolidine-4-carboxylic acid

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2021

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test)

Deviations:

not specified

Qualifier:

according to guideline

Guideline:

EU Method C.4-C (Determination of the "Ready" Biodegradability - Carbon Dioxide Evolution Test)

Deviations:

not specified

GLP compliance:

yes (incl. QA statement)

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, adapted

Remarks:

Activated sludge from a biologic sewage treatment plant was used as inoculum. The cho-sen plant treats mostly domestic sewage.

Details on inoculum:

Inoculum concentration: 25.0 mg/L
Temperature 19.7 – 21.7 °C without direct lighting
Duration 28 days

Duration of test (contact time):

28 d

Initial conc.:

20 mg/L

Based on:

IC (inorganic carbon)

Remarks:

The test was performed with a nominal start concentration of 20 mg organic carbon/L of the test item.

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

This study was performed in order to evaluate aerobic elimination and degradation potential of 3-acetylthiazolidine-4-carboxylic acid in a test for ready biodegradability, using a test item concentration of nominally 20 mg organic carbon/L 3-acetylthiazolidine-4-carboxylic acid.
The test item in a mineral medium was inoculated and incubated under aerobic conditions in the dark. The amount of organic carbon in the test solution due to the inoculum was kept as low as possible compared with the amount of organic carbon due to the test item. Allow-ance was made for the endogenous activity of the inoculum by running parallel blanks with inoculum but without test item. A positive control was run in parallel to check the operation of the procedures. Degradation was followed by determining the carbon dioxide produced. Measurements were taken at sufficiently frequent intervals to allow the identification of the beginning and end of biodegradation.
The test lasted for 28 days.

Key result

Parameter:

% degradation (CO2 evolution)

Value:

79

Sampling time:

28 d

Remarks on result:

readily biodegradable based on QSAR/QSPR prediction

Details on results:

• The test item 3-acetylthiazolidine-4-carboxylic acid is considered as “readily biode-gradable“.
• The degree of biodegradation reached 79 % after 28 days.
• The 10-day-window began on day 9, at its end, 77 % degradation were reached, sur-passing the pass level of 60 % given in the OECD guideline.
• Abiotic degradation was not observed.

1       Results and Validity

1.1      Results for the Test Item 3-acetylthiazolidine-4-carboxylic acid

• The test item 3-acetylthiazolidine-4-carboxylic acid is considered as “readily biodegradable“.


• The degree of biodegradation reached 79 % after 28 days.


• The 10-day-window began on day 9, at its end, 77 % degradation were reached, surpassing the pass level of 60 % given in the OECD guideline.


• Abiotic degradation was not observed.

1.2      Validity

All validity parameters and values are presented in the following table:

Table 9.2‑a    Validity

Parameter	Criterion	Found	Assessment
IC content of test item solution in medium	< 5% of TC	0 %	valid
CO2 emitted by the controls	< 70 mg/L	20.4 mg/L	valid
Difference within replicates	< 20%	10.4 %	valid
Degradation of positive control ≥ 60%	≤ 14 days	12 days	valid
Degradation in the toxicity flask on day 14	> 25%	60.8 %	non - toxic

 

 

 

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

the test item 3-acetylthiazolidine-4-carboxylic acid can be considered as “readily biode-gradable“

Executive summary:

The test item 3-acetylthiazolidine-4-carboxylic acid was tested using a concentration of nominally 20 mg organic carbon/L 3-acetylthiazolidine-4-carboxylic acid in test medium fol-lowing OECD 301B and EU-Method C.4-C.

Aniline was chosen as positive control.
Activated sludge was used as inoculum (concentration in the test 25.0 mg dry matter/L). The test was left running for 28 days.
All validity criteria were met. Degradation of the positive control surpassed the pass level of 60 % after 12 days.

The following data were determined for the test item 3-acetylthiazolidine-4-carboxylic acid:
10-day-window: day 9 – 19
degradation at the end of 10-day-window 77 %
degradation at the end of the test 79 %
pass level following guideline: 60 % at the end of 10-day-window for pure substances
respective 60 % at the end of the test for mixtures

Therefore, when applying the 10-day-window, 3-acetylthiazolidine-4-carboxylic acid is
readily biodegradable following OECD 301B and EU C.4-C respectively.

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Type of water:

freshwater