Sodium 2-methyl-2-[(1-oxoallyl)amino]propanesulphonate

Toxicity to microorganisms

Administrative data

Endpoint:

activated sludge respiration inhibition testing

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1996

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Well documented report of a guideline study conducted to GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1996

Report date:

1996

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test

Deviations:

yes

Remarks:

Stability and solubility of the test and reference substances were not studied.

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

2-Acrylamido-2-methylpropanesulfonic acid, ammonium salt

IUPAC Name:

2-Acrylamido-2-methylpropanesulfonic acid, ammonium salt

Constituent 2

Reference substance name:

Ammonium 2-methyl-2-[(1-oxo-2-propenyl)amino]-1-propanesulfonate

EC Number:

421-680-9

EC Name:

Ammonium 2-methyl-2-[(1-oxo-2-propenyl)amino]-1-propanesulfonate

IUPAC Name:

421-680-9

Constituent 3

Reference substance name:

58374-69-9

EC Number:

611-646-3

Cas Number:

58374-69-9

IUPAC Name:

58374-69-9

Details on test material:

- Name of test material (as cited in study report): OS 114454
- Substance type: organic
- Physical state: liquid
- Analytical purity: not specified
- Impurities (identity and concentrations): not specified
- Composition of test material, percentage of components: 100%
- Purity test date: not specified
- Lot/batch No.: not specified
- Expiration date of the lot/batch: not specified
- Stability under test conditions: stable
- Storage condition of test material: not specified

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Details on test solutions:

The test concentrations for the test substance were 1, 10, 100, 1,000 and 10,000 ppm (mg/l). The test substance was water-soluble. No organic solvents were used to facilitate the dispersion of the test substance. The test mixtures were well agitated by air flow at all times, and for test flasks with 1,000 and 10,000 ppm concentrations, magnetic stirring was employed to ensure dispersion of the test substance.

Test organisms

Test organisms (species):

activated sludge of a predominantly domestic sewage

Details on inoculum:

The inoculum used was the return sludge collected from a local waste-water treatment plant (Mentor, Ohio). On return to the laboratory the sludge was centrifuged and the supernatant decanted. The sludge was then washed in water three times by re-suspension and centrifugation. A small amount of the washed sludge was dried and weighed. From this result the amount of wet sludge was calculated to be suspended in water in order to obtain an activated sludge with a mixed liquor suspended solids level of 4 g/l (±10%). This level gave a concentration of 1.6 g/l in the test medium. The prepared sludge was maintained by continuous aeration and by addition of 30-50 ml synthetic sewage feed per litre of suspended sludge at the end of every working day.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

3 h

Post exposure observation period:

10 minutes

Test conditions

Hardness:

No specified

Test temperature:

Ambient (not monitored)

pH:

Not specified

Dissolved oxygen:

Not specified

Salinity:

Not specified

Nominal and measured concentrations:

Nominal concentrations: 1, 10, 100, 1,000 and 10,000 ppm (mg/l) of test substance

Details on test conditions:

TEST SYSTEM
- Test vessel: Erlenmeyer flasks
- Type (delete if not applicable): closed
- Size, fill volume: 1 litre flasks filled to 500 ml
- Aeration: continuous oil-free air, 0.5-1.0 litre/minute
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: 200 ml

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Distilled water

OTHER TEST CONDITIONS
- Adjustment of pH: no

EFFECT PARAMETERS MEASURED: respiration rate (mg O2/l.hr)

TEST CONCENTRATIONS
- Spacing factor for test concentrations: x10
- Range finding study: no

Reference substance (positive control):

yes

Remarks:

3,5 dichlorophenol

Results and discussion

Effect concentrations

Duration:

3 h

Dose descriptor:

EC0

Effect conc.:

10 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Results with reference substance (positive control):

- Results with reference substance valid? Yes
- Relevant effect levels: EC50/3 hours was in the accepted range of 5 to 30 mg/l

Any other information on results incl. tables

Activated Sludge, Respiration Inhibition Effect of OS 114454

	Concentration(ppm)	Log Concentration (ppm)	Respiration Rate (mg 02/l.hr)	Inhibition(%)
Control 1	-	-	42.1	-
Control 2	-	-	40.7	-
Test A-1	4	0.60	40.0	3
Test A-10	12	1.08	40.7	2
Test A-100	110	2.04	40.0	3
Test A-1000	1,022	3.01	44.4	-7
Test A-10000	10,000	4.00	41.4	0
Ref 10	10	1.00	25.5	38
Ref 20	20	1.30	9.8	76
Ref 40	40	1.60	5.5	87

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The test substance, up to the concentration of 10,000 ppm, did not show significant toxicity toward the microbial population. The EC50 was estimated to be >10,000 ppm and the NOEC estimated to be at 10,000 ppm.