methyl {4,6-diamino-2-[5-fluoro-1-(2-fluorobenzyl)-1H-pyrazolo[3,4-b]pyridin-3-yl]pyrimidin-5-yl}carbamate compd with dimethylsulfoxide

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:

25.07.2019 - 16.10.2019

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Report date:

2019

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

methyl {4,6-diamino-2-[5-fluoro-1-(2-fluorobenzyl)-1H-pyrazolo[3,4-b]pyridin-3-yl]pyrimidin-5-yl}carbamate compd with dimethylsulfoxide

EC Number:

818-416-3

Cas Number:

1438425-69-4

Molecular formula:

C19H16F2N8O2*2C2H6OS

IUPAC Name:

methyl {4,6-diamino-2-[5-fluoro-1-(2-fluorobenzyl)-1H-pyrazolo[3,4-b]pyridin-3-yl]pyrimidin-5-yl}carbamate compd with dimethylsulfoxide

Test material form:

solid

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

The aerobic activated sludge used for this study was deposited for 15 min, washed by centrifugation and the supernatant liquid phase was decanted. The solid material was re-suspended in test water and centrifuged again. This procedure was done three times. An aliquot of the final sludge suspension was weighed, dried and the ratio of wet sludge to its dry weight was determined. Based on this ratio, calculated aliquots of washed sludge suspension, corresponding to 3.5 g dry material per litre were mixed with test water (see 6.5) and aerated overnight. This suspension was used for the experiment.

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

100 mg/L

Based on:

ThOD

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

Type and Size:
Manometric Test System with test flasks containing a volume of approximately 500 mL.
Apparatus: BSB/BOD-Sensor-System
Principle: The test flasks prepared according paragraph 6.6 were incubated at 22°C * 1°C. The pressure decrease in the reaction vessels was measured over complete experimental phase of 28 days using the BSB/BOD-Sensor-System. The test flasks were closed gas-tight by a measuring head. Potassium hydroxide solution (45%) was used for trapping the produced carbon dioxide. The amount of O2 consumed by the activated sludge was calculated from the decrease of pressure in the reaction vessel.
Identification: Each test unit was uniquely identified with the study number, treatment and replicate number.

Surrounding Type: Climatised chamber
Temperature: 22°C ± 1°C
Light Conditions: Darkness
pH-Value of Test Solutions:
7.6 (measured at the start of the test)
7.5 to 8.1 (measured at the end of the test)

Recording:
Test conditions (temperature) were recorded continuously with suitable instruments, documented in the raw data and reported in the final report. (Short-term deviations (< 2 hours) from the recommended temperature range do normally not result in major disturbances of the test performance and were not reported.)
Reconstituted Test Water: Analytical grade salts were added to ultrapure water to prepare the following stock solutions:
a) 8.5 g KH2PO4, 21.75 g K2HPO4, 33.4 g Na2HPO4 x 2 H2O, 0.5 g NH4Cl filled up with ultrapure water to 1000 mL volume; The pH-value was 7.4.
b) 11.25 g MgSO4 x 7 H2O filled up with ultrapure water to 500 mL volume
c) 18.2 g CaCl2 x 2 H2O filled up with ultrapure water to 500 mL volume
d) 0.125 g FeCl3 x 6 H2O filled up with ultrapure water to 500 mL volume
In order to avoid precipitation of iron hydroxide in the stock solution d), one drop of concentrated HCl per litre was added before storage.
50 mL of stock solution a) and 5 mL of the stock solutions b) to d) were combined and filled up to a final volume of 5000 mL with ultrapure water.
The pH was adjusted to pH 7.6 with 1M HCL.

Reference substance

Reference substance:

benzoic acid, sodium salt

Results and discussion

% Degradation

Key result

Parameter:

% degradation (CO2 evolution)

Value:

0

Sampling time:

28 d

Remarks on result:

not determinable

Remarks:

Biodegradation could not be determined because of lacking information concerning the theoretical oxygen demand.

Details on results:

The mean biodegradation BAY 1021189 roh could not be determined. Since the theoretical oxygen demand of the test item was not determined, the biodegradation was assessed based on the readings of the pressure sensor.
Based on these readings, BAY 1021189 roh is expected to be not readily biodegradable.

BOD5 / COD results

Results with reference substance:

The reference item sodium benzoate was sufficiently degraded to 79% after 14 days and to 94% after 28 days of incubation, thus confirming the suitability of the aerobic activated sludge inoculum used.

Applicant's summary and conclusion

Validity criteria fulfilled:

no

Remarks:

Could not be determined because the ThOD was not determined based on sponsor request

Interpretation of results:

other: Expected to be not readily biodegradable

Conclusions:

Percentage Biodegradation:
The mean biodegradation of BAY 1021189 roh could not be determined. Since the theoretical oxygen demand of the test item was not determined based on Sponsor request, biodegradation was estimated based on the readings of the pressure sensor.
Based on these readings, BAY 1021189 roh is considered to be not readily biodegradable.

Executive summary:

Summary

Title:     BAY 1021189 roh: Ready Biodegradability in a Manometric Respirometry Test

               

Guidelines:       This study was designed to comply with the following methods:

               Commission Regulation 440/2008/EC, Method C.4-D of May 30, 2008: Manometric Respirometry Test (EEC Publication No. L 142/496, May 2008)

               OECD Guideline for Testing of Chemicals No. 301 F: "Ready Biodegradability: Manometric Respirometry Test", adopted July 17, 1992

Material and Methods:               

Test Item:          BAY 1021189 roh; Batch No.: FEY 7882-177-6

Test Species:    Aerobic activated sludge (microorganisms from a domestic waste¬water treatment plant) was supplied by the sewage treatment plant of Rossdorf, Germany.

Test Design:      The test item BAY 1021189 roh was investigated for its ready biodegradability in a manometric respirometry test over a period of 28 days. Due to Sponsor request the theoretical oxygen demand of the test item was not determined and therefore the biodegradation properties of the test item could not be assessed. As a reference item sodium benzoate was tested simultaneously under the same conditions as the test item, and functioned as a procedure control.

Endpoints:         Pressure measurements based on the metabolisation of the test item by the aerobic activated sludge microorganisms after 28 days of incubation.

Test Item Loading Rate (initial concentration in medium C0):    102.0 mg/L. The theoretical oxygen demand of the test item was not determined due to Sponsor’s request.

Reference Item:             Sodium Benzoate

Reference Item Loading Rate: 102.5 mg/L corresponding to an oxygen demand of about 170.7 mg/L (ThODNH4)

Test Conditions:             22°C ± 1°C, darkness

Results:

Biodegradation of BAY 1021189 roh:     The mean biodegradation BAY 1021189 roh could not be determined. Since the theoretical oxygen demand of the test item was not determined, the biodegradation was assessed based on the readings of the pressure sensor.

Based on these readings, BAY 1021189 roh is expected to be not readily biodegradable.

Biodegradation of Sodium Benzoate:   

The reference item sodium benzoate was sufficiently degraded to 79% after 14 days and to 94% after 28 days of incubation, thus confirming the suitability of the aerobic activated sludge inoculum used.

Biodegradation of the Toxicity Control:               

According to the test guidelines, the test item can be assumed to be not inhibitory to the aerobic activated sludge microorganisms because degradation was >25% within 14 days. Based on customer request the theoretical oxygen demand was not determined. Therefore the biodegradation of the toxicity control could not be determined. Still, the measured pressure values of the toxicity control indicate that the biodegradation was higher than 25% within 14 days