2-Pyridinecarbonitrile, 5-amino-3-(trifluoromethyl)-

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

26 Jan 2021 to 23 Feb 2021

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2021

Report date:

2021

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

July 1992

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: MEP, P.R. China, the Guideline for the Testing of Chemicals, Degradation and Accumulation No. 301F “Manometric Respirometry Test”

Version / remarks:

Second Edition (2013.9)

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

other: OECD Guidelines for the Testing of Chemicals, Revised Introduction to the OECD Guidelines for Testing of Chemicals, Section 3

Version / remarks:

March 2006

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

5-amino-3-(trifluoromethyl)pyridine-2-carbonitrile

EC Number:

815-137-9

Cas Number:

573762-62-6

Molecular formula:

C7H4F3N3

IUPAC Name:

5-amino-3-(trifluoromethyl)pyridine-2-carbonitrile

Details on test material:

- Appearence : Slightly yellowish brown fine powder
- CAS Number: 573762-62-6
- Molecular formula: C7H4F3N3
- Molecular weight: 187.12

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Analytical purity: 99.7%
- Batch n°: BI03K2005005
- Expiration date: 2021-06-02 (re-test date)
- Purity test date: 2020-06-15 (certificate of analysis release date)
STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition: at room temperature (15 - 25 °C)
- Stability under storage conditions: not indicated
- Stability under test conditions: not indicated
- Solubility or stability of the test item in the solvent/vehicle: not indicated
- Appearance: Almost white powder

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

- Source: domestic wastewater treatment plant, Shenyang North, P.R. China
- Collection: 1 days before the test exposure was started
- Pretreatment: no
- Concentration of sludge: the concentration of inoculum was not greater than 30 mg/L (as suspended solids (SS))

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

51.6 mg/L

Based on:

ThOD

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Composition of medium: test water prepared according to test guidelines.
* mineral stock solution A: 4.2523 g KH2PO4, 10.8757 g K2HPO4, 16.7010 g Na2HPO4.2H2O in 1 L Milli-Q water
* mineral stock solution B: 0.2507 g NH4Cl dissolved in 1 L Milli-Q water
* mineral stock solution C: 36.4 g CaCl2.2H2O dissolved in 1 L Milli-Q water
* mineral stock solution D: 22.5 g MgSO4.7H2O dissolved in 1 L Milli-Q water
* mineral stock solution E: 0.25 g FeCl3.6H2O, 0.56 K2-EDTA dissolved in 1 L Milli-Q water
* For 1 liter of mineral medium, 10 mL stock solution A was added to approximately 800 mL distilled water and the mixture stirred before adding, sequentially, 1 mL each of stock solutions B, C and D. After mixing, the mixture was made up to 1 liter with distilled water. In total 2 replicates of 10 L mineral medium were prepared. The pH of the mineral medium were 7.59 and 7.58, respectively.
- Suspended solids concentration: initially 30 mg dw/L
- Continuous darkness: yes
SAMPLING
- Sampling frequency: every day during 28 days
CONTROL AND BLANK SYSTEM
- Biotic control: yes, two replicates with inoculum
- Toxicity control: yes
- Procedure control: yes, 1 replicate with reference substance and inoculum

Reference substance

Reference substance:

benzoic acid, sodium salt

Remarks:

sodium benzoate

Results and discussion

Test performance:

The positive control item was biodegraded by at least 60% within 14 days, confirming suitability of the activated sludge.

% Degradation

Key result

Parameter:

% degradation (O2 consumption)

Value:

0

Remarks on result:

other: average of two replicates

Details on results:

The biodegradation of the reference substance (Sodium benzoate) attained 61.2% after day 4, 83.1% after 14 days and 94.3% after day 28.

Any other information on results incl. tables

In the Toxicity Control (TC) test mixture, more than 25% biodegradation occurred within 14 days (43.5%, based on ThOD). Therefore, the test item was considered not to inhibit microbial activity under test conditions.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Based on the results, the percentage biodegradation of T003630 within 28 days did not exceed the pass level of 60% biodegradation based on ThOD. The test item did not meet the criteria for “ready biodegradability” under the described test conditions.