2-ethoxy-5-(4-methyl-1-piperazinylsulfonyl)benzoic acid

Toxicity to microorganisms

Administrative data

Endpoint:

activated sludge respiration inhibition testing

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Conducted on 19 November 1996

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: done under GLP and OECD method

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1997

Report date:

1997

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: EC Directive 88/302 'Biodegradation-Activated Sludge Respiration Inhibition test' and OECD guideline No.209'

Principles of method if other than guideline:

The study was conducted in accordance with OECD Guideline for Testing of Chemicals No. 209 and EEC Methods for the Determination of Ecotoxicity, EEC Directive 67/548 Annex VIII Part C (87/302/EEC), Activated Sludge, Respiratiqn Inhibition Test
Cultures of activated sewage sludge were incubated with synthetic sewage under vigorous aeration and in the presence of the test substance. Aeration was interrupted after 3 hours and the rates of respiration measured electrochemically for each culture. Percentage inhibition of respiration was calculated for each culture after a 3 hour contact period by comparing oxygen depletion rates for the test substance with those for the negative control culture

GLP compliance:

yes

Test material

Test material information

Constituent 1

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

Intended use: Pharmaceutical intermediate
Appearance: White powder
Storage conditions: In darkness at room temperature
Expiry: Not supplied
Purity: >97 %
Date received: 2 October 1996

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
REFERENCE SUBSTANCE

Identity

3,5-Dichlorophenol (C6H3Cl2.0H)
Aldrich Chemical Co Ltd, Batch no. 41205, Purity 97%.

The reference substance was dissolved in dilution water with the aid of ultrasonic disruption

Sampling and analysis

Analytical monitoring:

no

Details on sampling:

check if analytical sampling done to verify concnetration

Test solutions

Vehicle:

no

Details on test solutions:

Test substance concentrations: 100mg/l in duplicate of test substance was dissolved directly in test water without the aid of auxiliary solvents or dispersing agents, with the aid of ultrasonic disruption

Reference substance: 3.2, 10 and 32 mg/l.
At time "O", 16 ml of synthetic sewage was made up to 300 ml with water in a 1 litre glass beaker. 200 ml of inoculum was added and the mixture aerated at approximately 0.5 - 1 litre per minute with compressed air via a narrow bore glass tube. This preparation was designated Control R1 Thereafter, at 15-minute intervals, further cultures were prepared following the same procedure but with the addition of appropriate amounts of test or reference substance to the vessels prior to adjusting the volume and adding the inoculum.

Test organisms

Test organisms (species):

sewage, domestic

Details on inoculum:

Type: A mixed population of activated sewage sludge micro-organisms.
Source: The aeration stage of the Anglian Water (Godmanchester) sewage treatment plant treating predominantly domestic sewage.
Preparation: A sample of activated sewage sludge was collected from the sewage treatment plant on 18 November 1996. The sample was maintained at 20°C with continuous aeration and used within 24 hours of collection. The pH was 7.9 and the suspended solids level of the sample was 7.2 g/l. Consequently, it was necessary to dilute the inoculum by a factor of two to obtain a suspended solid content of 3.6 g/l, to be within the 2 - 4 g/l range specified in the guidelines.




DILUTION WATER

Type


Laboratory tap water, dechlorinated by passage through activated carbon and softened by reverse osmosis (hardness approximately 120 - 180 mg/I as CaC03 , pH 7.5 ± 0.5).

Study design

Test type:

other: activated sewage sludge were incubated with synthetic sewage under vigorous aeration and in the presence of the test substance

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

3 h

Post exposure observation period:

As each culture reached 3 hours contact time its pH was recorded and the rate of respiration measured. A 280 ml darkened glass BOD bottle was completely filled with the culture and sealed by the Yellow Springs Dissolved Oxygen Meter (Model No. 57) dissolved oxygen probe whilst being stirred by a magnetic stirrer. The dissolved oxygen level was recorded for approximately 10 minutes (between approximately 6.5 and 2.5 mg02/l). Separate measuring bottles were used for control, test and reference cultures to eliminate the possibility of cross-contamination

Test conditions

Hardness:

No data

Test temperature:

21 °C

pH:

no data in report but was recorded

Dissolved oxygen:

dissolved oxygen level was recorded for approximately 10 minutes (between approximately 6.5 and 2.5 mg02/l).

Salinity:

No Data

Nominal and measured concentrations:

UK-143,108:

3,5-dichlorophenol:
EC50 (3 hours):> 100 mg/I.
EC50 (3 hours):13 mg/l

Details on test conditions:

TEST SYSTEM: series
- Test vessel: 1 liter glass beaker
- Aeration: yes
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2

test has test substance+synthetic sewage + inoculumn
controls has synthetic sewage + inoculumn only

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Laboratory tap water, dechlorinated by passage through activated carbon and softened by reverse osmosis (hardness approximately 120 - 180 mg/I as CaC03 , pH 7.5 ± 0.5).
TEST CONCENTRATIONS
- Test concentrations: Test substance: 100 mg/l in duplicate. Reference substance: 3.2, 10 and 32 mg/l.

Reference substance (positive control):

yes

Remarks:

3.5 dichlorophenyl

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

3 h

Dose descriptor:

EC50

Effect conc.:

> 0 - < 100 mg/L

Remarks on result:

other: UK-143,108

Effect concentrations 2

Duration:

3 h

Dose descriptor:

EC50

Effect conc.:

13 mg/L

Remarks on result:

other: 3,5-dichlorophenol

Details on results:

Variation in respiration rates of Controls 1 and 2: ± 2 % .

Results with reference substance (positive control):

3,5-dichlorophenol:EC50 (3 hours): 13 mg/I

Reported statistics and error estimates:

No Data

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

The validation criteria for (i) Control culture respiration and (ii) respiration inhibition by the reference substance, were fulfilled during this study

Conclusions:

The EC50 (respiration inhibition) value for UK-143, 108 with activated sewage sludge has been determined as > 100 mg/I for the 3 hour contact time.