Fatty acids, C12-18 and C18-unsatd., 2-sulfoethyl esters, sodium salts

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2007-07-18 to 2008-03-03

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Study conducted according to GLP and OECD (202) (Guidelines for Testing of Chemicals. Section 2. Guideline 202 "Daphnia sp. Acute Immobilisation Test" (2004)). The analytical chemistry supporting this study was performed to GLP and confirms the identity of the test item but, the separate chemistry report has not been audited at the current time (04 November 2010).

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2008

Report date:

2008

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Reference

Name:

Unnamed

Type:

Constituent

Details on test material:

Name of test material as cited in test report: Sodium Cocoyl Isethionate Common name SLI (76) Stripped.

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
Not applicable

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Nominal Concentrations: 0, 18, 32, 56, 100, 180 mg/L
- Sampling method: Test item concetrations (Nominal 18, 32, 56, 100 and 180 mg/L) were determined at 0, 24 and 48 hrs. The stock solution and test media were removed and renewed after 24 hours and concentrations determined using LC/MS.
- Sample storage conditions before analysis: No data provided.

Test solutions

Details on test solutions:

A nominal 1800 mg/L stock solution was prepared by adding 1800 mg of SLI (76) stripped to 1000 mL of purified water. The solution was heated to approximately 40-50 degrees C whilst stirring continuously until test item dissolved. Test media were prepared by diluting the warm 1800 mg/L stock solution with Elendt M7 medium to obtain nominal test concentrations of 0, 18, 32, 56, 100 and 180 mg/L. The test solutions were left to stand for 1 hour after preparation to allow for settling of the test item precipitate. The resulting supernatant was decanted and used as the final test media.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Age at study initiation (mean and range, SD):<24 hrs old
- Daphnia were not fed duing the test


ACCLIMATION
- Acclimation period: <24 h
- Acclimation conditions (same as test or not): no data
- Type and amount of food: no food
- Feeding frequency: not applicable
- Health during acclimation (any mortality observed): no data

Study design

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Remarks on exposure duration:

h

Post exposure observation period:

None

Test conditions

Hardness:

Measured in 0 and 180 mg/L nominal test solutions at 0, 24 and 48 hrs. Mean = 276 (SD = 10) mg/L as CaCO3

Test temperature:

The temperature was measured in five random test vessels at 0, 24 and 48 hrs. Mean = 20.0 (SD = 0.6) degrees C

pH:

The pH was measured in all test concentrations at 0, 24 and 48 hrs. Mean = 7.6 (SD = 0.2)

Dissolved oxygen:

The dissolved oxygen concetration was measured in all test concentrations at 0, 24 and 48 hrs. Mean = 8.0 (SD = 1.2) mg/L

Salinity:

No data

Nominal and measured concentrations:

Nominal: 0, 18, 32, 56, 100 and 180 mg/L
Measured concentrations reported as time weighted averages for both total and dissolved:
Total measured concentrations: 15.7, 29.1, 49.8, 101.6 and 169.2 mg/L
Dissolved measured concentrations: 10.8, 19.6, 34.6, 50.1 and 80.6 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 120 mL crytallising dish

- Renewal rate of test solution (frequency/flow rate): every 24 hours
- No. of organisms per vessel: five
- No. of vessels per concentration (replicates): four replicates per concentration
- No. of vessels per control (replicates): four
- No. of vessels per vehicle control (replicates): not applicable
- Biomass loading rate: no data

TEST MEDIUM / WATER PARAMETERS
Elendt M7 media. No details provided.

OTHER TEST CONDITIONS
Normal laboratory light intensity with photoperiod of 16 h light and 8 h dark.


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
Immobility in the Daphnia is due mainly to indirect effects. At 48 hours the Daphnia exposed to 56 mg/L (nominal) SLI(76) stripped were fully mobile however there was evidence of the precipitate adhering to the carapace and antennae. Similarly at 100 mg/L (nominal), the majority of the Daphnia were coated in precipitate around the head, carapace and antennae although they were still considered mobile. At 180 mg/L (nominal), individuals were severely hindered by test precipitate and were considered immobile according to the criteria set by OECD i.e. unable to swim after 15 seconds agitation. It should be noted however that no mortality was observed.

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 101.6 mg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

act. ingr.

Basis for effect:

mobility

Remarks on result:

other: 95% Confidence Interval

Effect concentrations 2

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 50 mg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

dissolved

Basis for effect:

mobility

Remarks on result:

other: 95% confidence interval

Details on results:

None of the concetrations caused 100% immobility.

Immobility in the Daphnia is due mainly to indirect effects. At 48 hours the Daphnia exposed to 56 mg/L (nominal) SLI(76) stripped were fully mobile however there was evidence of the precipitate adhering to the carapace and antennae. Similarly at 100 mg/L (nominal), the majority of the Daphnia were coated in precipitate around the head, carapace and antennae although they were still considered mobile. At 180 mg/L (nominal), individuals were severely hindered by test precipitate and were considered immobile according to the criteria set by OECD i.e. unable to swim after 15 seconds agitation. It should be noted however that no mortality was observed and it is believed that without the precipitation no effects would have been observed.

Results with reference substance (positive control):

Not applicable

Reported statistics and error estimates:

95% confidence intervals

Any other information on results incl. tables

TABLE 1. SUMMARY OF SLI (76) STRIPPED CONCENTRATIONS during 48 hour Daphnia magna study

Nominal concentration (mg/L)	Measured concentration (mg/L)								Mean measured concentration (mg/L)*
	0 hours		24 hrs (old)		24 hrs (new)		48 hrs
	Total	Dissolved	Total	Dissolved	Total	Dissolved	Total	Dissolved	Total	Dissolved
18	17.7	10.1	17.4	15.4	18.7	10.3	10.0	7.9	15.7	10.8
32	30.3	15.4	31.4	27.6	31.6	17.3	23.5	19.4	29.1	19.6
56	53.4	39.4	50.1	37.4	54.3	41.0	42.1	22.4	49.8	34.6
100	102.8	54.4	93.9	40.7	103.8	67.8	106.1	40.4	101.6	50.1
180	169.6	100.6	155.9	61.1	168.6	116.9	183.2	54.8	169.2	80.6

* calculated as time weighted means

Table 2. 24 & 48 hour immobility data

Nominal	% immobility
Conc (mg/L)	at 24 hrs	at 48 hrs
0.0	0	0
18	0	0
32	0	0
56	0	0
100	0	0
180	10	60

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The 48-hour EC50 of SLI(76) stripped to juvenile (<24 h old) Daphnia magna based on total mean measured concentrations was > 101.6 (95 % confidence intervals). The 48-hour EC50 based on dissolved mean measured concentrations was >50.0 (95 % confidence intervals).

Executive summary:

The 48-hour EC50 of SLI(76) stripped to juvenile (<24 h old) Daphnia magna, under semi-static conditions, based on total mean measured concentrations was > 101.6 (95 % confidence intervals). The 48-hour EC50 based on dissolved mean measured concentrations was >50.0 (95 % confidence intervals). Test concentrations were determined throughout the study by LC/MS. The study was conducted according to GLP and OECD (202) testing guideline.