1,1,2,2,3,3,4,4,4-nonafluorobutane-1-sulphonic acid

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

22 Jan - 1 Feb 2001

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2001

Report date:

2001

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Freshwater Alga and Cyanobacteria, Growth Inhibition Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EPA OPPTS 850.5400 (Algal Toxicity, Tiers I and II) (January 2012)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Potassium 1,1,2,2,3,3,4,4,4-nonafluorobutane-1-sulphonate

EC Number:

249-616-3

EC Name:

Potassium 1,1,2,2,3,3,4,4,4-nonafluorobutane-1-sulphonate

Cas Number:

29420-49-3

Molecular formula:

C4HF9O3S.K

IUPAC Name:

potassium 1,1,2,2,3,3,4,4,4-nonafluorobutane-1-sulfonate

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: L-7038 Lot 2
- Expiration date of the lot/batch: 17 Jan 2002
- Purity: 97.3%

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: ambient conditions
- Stability under test conditions: stable

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: All concentrations monitored
- Sampling method: Three replicate test chambers were maintained for each treatment and control group. One additional replicate was also maintained for analytical sampling at 72 hours. Test solutions from the same concentration were pooled before sampling at 96 hours. The bulk test solution stocks fwere sampled at the initial time point. A sample was taken from all test concentrations and the control at test initiation, at approximately 72 hours, and at test termination.
- Sample storage conditions before analysis: samples stored in plastic vials and analyzed as soon as possible without storage
- Abiotic samples: To verify maintenance of the test substance concentration, two replicates were set up at the highest substance concentration but without algae. Measured test concentrations were determined at test initiation, at approximately 72 hours, and at test termination.
To verify maintenance of test substance concentration, a test vessel was set up at the highest substance concentration but without algae. Samples for analysis were taken at times zero, 24h and 72h.

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: A 2-L primary stock solution was prepared in algal medium at a concentration of 10000 mg a.i./L. The primary stock solution was inverted at least 20 times to aid in the solubilization of the test substance. After mixing, the primary stock solution was proportionally diluted with algal medium to prepare 500 mL of the five other test concentrations (313, 625, 1250, 2500, 5000 mg a.i./L). All dilutions were inverted to mix.
- Controls: Test medium without test substance or other additives
- Evidence of undissolved material (e.g. precipitate, surface film, etc.): none, test solutions were clear and colorless at start of test

Test organisms

Test organisms (species):

Raphidocelis subcapitata (previous names: Pseudokirchneriella subcapitata, Selenastrum capricornutum)

Details on test organisms:

TEST ORGANISM
- Common name: Selenastrum capricornutum
- Source (laboratory, culture collection): Internal stock at Wildlife International, Ltd. Inoculum originally obtained from University of Toronto, Canada.
- Age of inoculum: not reported
- Method of cultivation: Algal cells used in this test were obtained from Wildlife International, LtdCultures that had been actively growing in culture medium for at least two weeks prior to test initiation.

ACCLIMATION
- Acclimation period: none
- Culturing media and conditions: The algal cells were cultured and tested in freshwater algal medium. The pH of the medium was adjusted to 7.5 ± 0.1 using 10% HCl; the medium was sterilized by filtration (0.22 µm) prior to use.

MgCl2·6H2O, 12.16 mg/L
CaCl2·2H2O, 4.41 mg/L
H3BO3, 0.1855 mg/L
MnCl2·4H2O, 0.4154 mg/L
ZnCl2, 3.27 mg/L
FeCl3·6H2O, 0.1598 mg/L
CoCl2·6H2O, 1.428 mg/L
Na2MoO4·2H2O, 7.26 mg/L
CuCl2·2H2O, 0.012 mg/L
Na2EDTA·2H2O, 0.300 mg/L
NaNO3, 25.50 mg/L
MgSO4·7H2O, 14.70 mg/L
K2HPO4, 1.044 mg/L
NaHCO3, 15.0 mg/L

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

The 9478 mg a.i./L treatment group was maximally inhibited at the end of the 96-hour exposure period. Aliquots of the test solution were diluted with algal medium and cultured for six days. Based on the growth observed in the recovery phase, the effect on algal growth was found to be algistatic.

Test conditions

Test temperature:

23.8 - 24.7 °C

pH:

0 hours: 6.9 - 7.1
96 hours: 7.5 - 8.7

Nominal and measured concentrations:

Nominal: 0 (negative control), 313, 625, 1250, 2500, 5000, and 10000 mg/L
Measured: < LOQ, 285, 563, 1077, 2216, 4561, and 9478 mg/L (see Table 1)

Details on test conditions:

TEST SYSTEM
- Test vessel: 250 mL polycarbonate Erlenmeyer flasks plugged with foam stoppers and 100 mL of test or control algal medium
- Type: closed
- Agitation: Yes, the test chambers were shaken continuously at 100 rpm
- Initial cells density: 1.0E+04 cells/mL
- Control end cells density: 3.56E+06 cells/mL
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 3

GROWTH MEDIUM
- Standard medium used: yes (ASTM Standard Guide 1218-90E)

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: purified well water (reverse osmosis)

OTHER TEST CONDITIONS
- Photoperiod: Continuous cool-white fluorescent lighting (4300 ± 430 lux) measured using SPER Scientific Model 840006 light meter

EFFECT PARAMETERS MEASURED:
- Determination of cell concentrations: cell counts were conducted using a hemacytometer and microscope at 24 hour intervals

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

5 661 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

growth rate

Remarks on result:

other: 95% CI: 5230-6067 mg a.i./L

Effect concentrations 2

Key result

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

734 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

growth rate

Remarks on result:

other: 95% CI: 0-2207 mg a.i./L

Effect concentrations 3

Duration:

96 h

Dose descriptor:

EC50

Effect conc.:

5 733 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

growth rate

Remarks on result:

other: 95% CI: 5659-5817 mg a.i./L

Effect concentrations 4

Duration:

96 h

Dose descriptor:

EC10

Effect conc.:

1 674 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

growth rate

Remarks on result:

other: 95% CI: 1482-1839 mg a.i./L

Details on results:

- Exponential growth in the control: yes
- Observation of abnormalities: After 96 hours of exposure, there were no signs of aggregation, flocculation, or adherence of the algae to the test flasks in the control or treatment groups. However, algal cells in the 2216, 4561, and 6478 mg a.i./L treatment groups appeared enlarged when compared to the negative control.
- Other: The 9478 mg a.i./L treatment group was maximally inhibited at the end of the 96-hour exposure period. Aliquots of the test solution were diluted with algal medium and cultured for six days. Based on the growth observed in the recovery phase, the effect on algal growth was found to be algistatic.

Reported statistics and error estimates:

After 72 hours of exposure, Dunnett’s test showed that growth rate was significantly reduced in all treatment groups (p = 0.05). After 96 hours of exposure, Dunnett’s test showed that growth rate was significantly reduced in the 2216, 4561, and 9478 mg a.i./L treatment groups (p = 0.05).

Any other information on results incl. tables

Table 2. Cell Densities over 96-Hour Exposure Period

		Cell Densities (cells/mL)
Mean Measured Concentration (mg a.i./L)	Replicate	24 hours	48 hours	72 hours	96 hours
Negative Control	A	21000	168000	1200000	3735000
	B	25000	184000	1045000	3420000
	C	47000	185000	800000	3525000
285	A	29000	157000	625000	4005000
	B	26000	152000	730000	3930000
	C	36000	178000	710000	3825000
563	A	25000	136000	645000	3120000
	B	30000	126000	625000	3195000
	C	26000	154000	750000	3480000
1077	A	24000	133000	720000	3750000
	B	17000	106000	465000	3180000
	C	21000	118000	530000	3150000
2216	A	19000	88000	430000	2025000
	B	14000	97000	330000	1845000
	C	19000	101000	395000	1920000
4561	A	12000	51000	171000	850000
	B	17000	80000	188000	870000
	C	17000	56000	167000	860000
9478	A	17000	13000	16000	19000
	B	4000	15000	16000	15000
	C	15000	20000	12000	12000

Table 3. Mean Growth Rates and Percent Inhibition at 24-hour Time Intervals

		Growth Rate
Mean Measured Concentration (mg a.i./L)	Replicate	0-24 hours	24-48 hours	48-72 hours	72-96 hours	0-72 hours	0-96 hours
Negative Control	A	0.0309	0.0866	0.0819	0.0473	0.0665	0.0617
	B	0.0382	0.0832	0.0724	0.0494	0.0646	0.0608
	C	0.0645	0.0571	0.0610	0.0618	0.0609	0.0611
285	A	0.0444	0.0704	0.0576	0.0774	0.0574	0.0624
	B	0.0398	0.0736	0.0654	0.0701	0.0596	0.0622
	C	0.0534	0.0666	0.0576	0.0702	0.0592	0.0619
563	A	0.0382	0.0706	0.0649	0.0657	0.0579	0.0598
	B	0.0458	0.0598	0.0667	0.0680	0.0574	0.0601
	C	0.0398	0.0741	0.0660	0.0639	0.0600	0.0610
1077	A	0.0365	0.0713	0.0704	0.0688	0.0594	0.0617
	B	0.0221	0.0763	0.0616	0.0801	0.0533	0.0600
	C	0.0309	0.0719	0.0626	0.0743	0.0551	0.0599
2216	A	0.0267	0.0639	0.0661	0.0646	0.0522	0.0553
	B	0.0140	0.0807	0.0510	0.0717	0.0486	0.0544
	C	0.0267	0.0696	0.0568	0.0659	0.0511	0.0548
4561	A	0.0076	0.0603	0.0504	0.0668	0.0394	0.0463
	B	0.0221	0.0645	0.0356	0.0638	0.0407	0.0465
	C	0.0221	0.0497	0.0455	0.0683	0.0391	0.0464
9478	A	0.0221	-0.0112	0.0087	0.0072	0.0065	0.0067
	B	0.000	0.0551	0.0027	-0.0027	0.0065	0.0042
	C	0.0169	0.0120	-0.0213	0.0000	0.0025	0.0019

The mean CV for section specific growth rates in the control was 29%, and the CV of average specific growth rates during the whole test period in control was 4.4%

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

Control cell density increased by an average factor of >16 within 2 days, the mean CV for section specific growth rates in the control was < 35% (29%), and the CV of average specific growth rates during the whole test period in control was < 7% (4.4%).

Conclusions:

The 72-hour EC50 (growth rate) of PFBSK+ to Pseudokirchneriella subcapitata was 5661 mg a.i./L. The corresponding 72-hour EC10 (growth rate) was 734 mg a.i./L. Test conducted per OECD 201.

Executive summary:

The toxicity of PFBSK+ to the green algae, Pseudokirchneriella subcapitata, was assessed according to the OECD 201 method. An exponential growth was observed during the entire period of exposure in the control vessel and the validity criteria were met.

The 72-hour ErC50 of PFBSK+ to Pseudokirchneriella subcapitata for growth rate was 5661 mg a.i./L (5230-6067 mg a.i./L). The corresponding 72-hour ErC10 was 734 mg/L (95% CI: 0-2207 mg/L). Based on the growth observed in the recovery phase, the effect on algal growth was found to be algistatic.

The study was performed in accordance with internationally-accepted test guidelines under GLP. The study is deemed reliable without restriction and suitable for use in Risk Assessment, Classification & Labeling, and PBT Analysis.