(R)-thiazolidine-4-carboxylic acid

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Report date:

2020

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

(R)-thiazolidine-4-carboxylic acid

EC Number:

252-106-3

EC Name:

(R)-thiazolidine-4-carboxylic acid

Cas Number:

34592-47-7

Molecular formula:

C4H7NO2S

IUPAC Name:

(R)-thiazolidine-4-carboxylic acid

Test material form:

solid: particulate/powder

Specific details on test material used for the study:

Batch no. 20190104
Expiry date January 01, 2021
Purity 99.3% w/w

Study design

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Duration of test (contact time):

28 d

Initial test substance concentration

Initial test substance concentration 1

Initial conc.:

90 mg/L

Based on:

ThOD

Initial test substance concentration 2

Initial conc.:

50 mg/L

Based on:

test mat.

Details on study design:

Since the test ite was not soluble in water, test flasks were prepared weighing proper amount of test item directly in mineral medium. The proper volume of stock solution was dosed in the test flasks to obtain the final conc. of 50.0 mg/l of test item.
Activated sludge was added to each flask /with the exception of the abiotic control) before incubation.

Reference substance

Reference substance:

benzoic acid, sodium salt

Results and discussion

% Degradation

% Degradation 1

Parameter:

% degradation (O2 consumption)

Value:

82.8

Sampling time:

10 d

% Degradation 2

Parameter:

% degradation (O2 consumption)

Value:

72.9

Sampling time:

28 d

Details on results:

All results are related to the nominal concentration, since the test conc. were not measured during the test.
The biodegradation was followed by measuring the oxygen uptake (mg/l) of the test item under defined conditions by the means of a manometric method and calculating from these values the BOD.
The ThOD NH3 value was calculated to be equal to 1.67 mg O2/mg for reference item, Sodium benzoate, while ThOD NH3 value was assessed to be 1.80 mg O2/mg for the test item.
These value were used to calculate per % biodegradation.

BOD5 / COD results

Results with reference substance:

The reference item exceed (99.4%) the biodegradation pass level of 60%.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

The test item was found to be ready and completely biodegradable since at the end of the 10-day window the biodegradation was 82.8% and at the end of the test and after nitrification correction, a maximum biodegradation of 72.9% was found (mean % values between two replicates).
No significant degradation was observed in the abiotic control.
No inhibitory effects on the microorganism activity at the tested concentration, as demonstrated by the biodegradation percentage in the toxicity control exceeding the 25% pass level within 14 days of exposure (47.9%)