1,1,2,2,3,3,4,4,4-nonafluoro-N-methylbutane-1-sulfonamide

Toxicity to microorganisms

Administrative data

Endpoint:

activated sludge respiration inhibition testing

Type of information:

experimental study

Adequacy of study:

key study

Study period:

January 30, 2002

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2002

Report date:

2002

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test

Deviations:

no

GLP compliance:

no

Remarks:

Screening level assay. GLP compliance was not required at the time of the test.

Test material

Test material information

Constituent 1

Reference substance name:

1,1,2,2,3,3,4,4,4-nonafluoro-N-methylbutane-1-sulfonamide

EC Number:

614-396-3

Cas Number:

68298-12-4

Molecular formula:

C5H4F9NO2S

IUPAC Name:

1,1,2,2,3,3,4,4,4-nonafluoro-N-methylbutane-1-sulfonamide

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch number of test material: 3M. Lot #3
- Purity: 97.25%
- Physical state: Off white crystalline powder

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Ambient conditions

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Test substance directly weighed into the test vessel.
- Controls: Blank control and reference controls

Test organisms

Test organisms (species):

activated sludge

Details on inoculum:

- Name and location of sewage treatment plant where inoculum was collected: Activated sludge collected on January 28th, 2002 (two days prior to test) from Denton Wastewater Treatment Facility, Denton Maryland.
- Total Suspended Solids: 3633 mg/L
- pH for sludge: 7.8

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

3 h

Test conditions

Test temperature:

20-21°C

Nominal and measured concentrations:

Nominal: Blank control, 10, 100, 1000 mgL; Reference control: 3, 15, 50 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Exposure was in 500mL erlenmeyer flasks and then solution was tansferred to 300 mL Biochemical Oxygen Demand bottles
- Aeration: 3 hours
- No. of vessels per concentration (replicates): The 10, 100, and 1000 mg/L solutions were tested with 1 replicate.
- No. of vessels per control (replicates): two for blank control
- Nutrients provided for bacteria: synthetic sewage per OECD 209 (peptone 16g, meat extract 11.0 g, urea 3.0 g, NaCl 0.7 g, CaCl2.2H2O 0.4 g, MgSO4.7H2O 0.2 g, K2HPO4 2.8 g (dissolved in 1 L of water).
- Test setup: The test substance was added directly to the test system vessels by direct weight addition. Sludge was aerated until measurement.

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

OTHER TEST CONDITIONS:
Details on termination of incubation: After a 3 hour exposure, test solutions were transferred to a 300 mL BOD for measurement.

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Respiration inhibition. Dissolved oxygen (DO) concentrations were measured using a YSI Model 50B Dissolved Oxygen Meter. Readings were recorded every 10 seconds for 10 minutes until the DO dropped below 1.0 mg/L.

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 10x
- Range finding study : No

Reference substance (positive control):

yes

Remarks:

3, 5-dichlorophenoL

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

3 h

Dose descriptor:

EC50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks on result:

other:

Remarks:

No inhibition observed at highest concentration tested.

Effect concentrations 2

Key result

Duration:

3 h

Dose descriptor:

NOEC

Effect conc.:

1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks on result:

other:

Remarks:

No inhibition observed at highest concentration tested.

Details on results:

- Coefficient of variation of oxygen uptake rate in control replicates: 13%
-Inhibition for 1000 mg/L concentration = -41.5%

Results with reference substance (positive control):

The EC50 for 3,5-dichlorophenol reference group was 28.3 mg/L
- Results with reference substance valid? Yes, within the 5-30 mg/L range considered acceptable for the test.

Any other information on results incl. tables

Table 1. Respiration Rate and Percent Inhibition

Treatment	Respiration Rate (mg O2/L/hour)	Percent inhibition
Control (1)	52.7	NA
Control (2)	46.1	NA
Reference Control (3 mg/L)	50.9	-3.0
Reference Control (15 mg/L)	42.4	14.2
Reference Control (50 mg/L)	8.5	82.8
MeFBSA (10 mg/L)	87.4	-76.9
MeFBSA (100 mg/L)	66.9	-35.4
MeFBSA (1000 mg/L)	66.9	-41.5

*Reference control was 3,5-dichlorophenol

Applicant's summary and conclusion

Validity criteria fulfilled:

not specified

Remarks:

Control oxygen uptake rate >20 mg O2/gram sludge/hour (No information); coeff. of variation <15% for control replicates (13%); ref substance EC50 in range 5-30 mg/L (28.3 mg/L).

Conclusions:

3 hour EC50>1000 mg/L in activated sludge for respiration inhibition (OECD 209)
3 hour NOEC=1000 mg/L in activated sludge for respiration inhibition (OECD 209)

Executive summary:

The toxicity of MeFBSA to activated sludge was assessed according to the OECD 209 guideline in a screening assay conducted at 10, 100, and 1000 mg/L. The validity criteria were partially met based on acceptable variation among control replicates and a typical level of inhibition with the positive control. The 3-hour EC50 (respiration) of MeFBSA to activated sludge is >1000 mg/L, as no inhibition was observed. The study followed an international standard method and but is not GLP compliant and lacks key details including biomass loading rate. However, the study included a positive control indicating normal susceptibility of sludge. The study is deemed reliable with restrictions and can be utilized to calculate a PNEC for STP.