Registration Dossier

Environmental fate & pathways

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:
2015-06-09 to 2015-07-31
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2015
Report Date:
2015

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test)
Deviations:
no
Qualifier:
according to
Guideline:
EU Method C.4-C (Determination of the "Ready" Biodegradability - Carbon Dioxide Evolution Test)
Deviations:
no
Qualifier:
according to
Guideline:
ISO DIS 9439 (Ultimate Aerobic Biodegradability - Method by Analysis of Released Carbon Dioxide)
Deviations:
no
Qualifier:
according to
Guideline:
other: ISO International Standard 10634 "Water Quality - Guidance for the preparation and treatment of poorly water-soluble organic compounds for the subsequent evaluation of their biodegradability in an aqueous medium"
Deviations:
no
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: particulate/powder
Remarks:
migrated information: powder
Details on test material:
- Name of test material (as cited in study report): JNJ-150098-AAC (T001310)
- Physical state: white powder
- Analytical purity: base titration = 97.4 % - acid titration = 98.7%
- Lot/batch No.: I14KB4913
- Expiration date of the lot/batch: 2020-11-23
- Storage condition of test material: at room temperature
- solubility in water: 320 g/L
Specific details on test material used for the study:
Batch I14KB4913
Purity/Composition 97.4%
Test item storage conditions At room temperature
Stable under storage conditions until 23 November 2020 (retest date)

Study design

Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge, domestic, non-adapted
Details on inoculum:
- Source: municipal sewage treatment plant receiving predominantly domestic sewage, 'Waterschap Aa en Maas', 's-Hertogenbosch, The Netherlands.
- Preparation of inoculum for exposure: sludge was kept under continuous aeration until further treatment. Before use, the sludge was allowed to settle (34 minutes) and the supernatant liquid was used as inoculum.
- Concentration of sludge: The concentration of suspended solids was determined to be 4.3 g/L in the concentrated sludge.

Duration of test (contact time):
28 d
Initial test substance concentration
Initial conc.:
27.5 mg/L
Based on:
test mat.
Parameter followed for biodegradation estimation
Parameter followed for biodegradation estimation:
CO2 evolution
Details on study design:
TEST CONDITIONS
- Composition of medium: test water prepared according to test guidelines, analytical grade salts were dissolved in tap-water purified by reverse osmosis (Milli-RO) and subsequently passed over activated carbon. A stock solution of 1 g/L in Milli-RO water was used. Aliquots of 55 mL of the stock solution were added to the test substance bottles and to the toxicity control. The test solutions were continuously stirred during the test.
- Additional substrate: no
- Test temperature: 22-24°C
- pH: 7.47-7.7, measured prior to testing in each test flask before addition of inoculum, and again in each test flask at the end of the incubation period
- pH adjusted: no
- Aeration of dilution water: The test solutions were continuously stirred and aerated during the test.
- Continuous darkness: yes

TEST SYSTEM
- Test flasks: 2 L glass brown coloured bottles
- Number of culture flasks/concentration: 2
- Method used to create aerobic conditions: A mixture of oxygen (~20%) and nitrogen (~80%) was passed through a bottle, containing 0,5 - 1 L 0,0125 M Ba(OH)2 solution to trap CO2. The synthetic air was sparged through the scrubbing solutions at a rate of ~1-2 bubbles per second ( ~30-100 mL/min).
- Details of trap for CO2 and volatile organics if used: 3 CO2-absorbers (bottles filled with 100 mL 0,0125 M Ba(OH)2) were connected in series to the exit air line of each bottle. The CO2 produced in each test bottle reacted with the barium hydroxide in the gas scrubbing bottle and precipitated out as barium carbonate. The amount of CO2 produced was determined by titrating the remaining ba(OH)2 with 0,05 M standardized HCl.

CONTROL AND BLANK SYSTEM
- Inoculum blank: yes, two replicates with only inoculum
- Toxicity control: yes, one replicate with test item, reference substance, and inoculum
- Procedure control: yes, 1 replicate with reference item and inoculum
Reference substance
Reference substance:
acetic acid, sodium salt

Results and discussion

% Degradation
Parameter:
% degradation (CO2 evolution)
Value:
ca. 5
Sampling time:
28 d
Details on results:
No significant biodegradation of the test item occurred within 28 days of incubation (4% and 6%, based on ThCO2 ). The toxicity controls indicated that the test item did not have an inhibitory effect on the microbial activity.

BOD5 / COD results

Results with reference substance:
The positive control item was biodegraded by at least 60% (72%) within 14 days, confirming suitability of the activated sludge.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Interpretation of results:
not readily biodegradable
Conclusions:
A 28-d ready biodegradability test (OECD 301B, modified sturm test) using unadapted activated sludge from a predominantly domestic waste water treatment plant indicated that JNJ-150098-AAC (T001310) was not readily biodegradable under the conditions of the test (initial concentration 27.5 mg/L corresponding to 12 mg TOC/L). The results of the test can be considered reliable without restriction.