Short-term toxicity to aquatic invertebrates.008

Short-term toxicity to aquatic invertebrates.008

Administrative data

Purpose flag:

key study

Study result type:

experimental result

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1996

Materials and methods

Test guideline

Qualifier:

according to

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

GLP compliance:

yes

Remarks:

no GLP certificate was joined

Test materials

Identity of test material same as for substance defined in section 1 (if not read-across):

yes

Test material identityopen allclose all

Test material identity 1

Identifier:

CAS number

Identity:

10049-04-4

Test material identity 2

Identifier:

EC number

Identity:

233-162-8

Details on test material:

- Name of test material (as cited in study report): Chlorine dioxide
- Molecular formula (if other than submission substance): no data
- Molecular weight (if other than submission substance): no data
- Smiles notation (if other than submission substance): no data
- InChl (if other than submission substance): no data
- Structural formula attached as image file (if other than submission substance): no data
- Substance type: Yellow liquid
- Physical state: liquid
- Analytical purity: no data
- Impurities (identity and concentrations): no data
- Composition of test material, percentage of components: 2 g/L of chlorine dioxide (nominal) 
- Isomers composition: no data
- Purity test date: no data
- Lot/batch No.: prepared on 1995-03-09
- Expiration date of the lot/batch: no data
- Stability under test conditions: 6 months from the preparation date
- Storage condition of test material: in the dark at +4°C

Details on properties of test surrogate or analogue material:

no data

Analytical monitoring:

yes

Details on sampling:

Dissolved oxygen, pH, temperature and test substnace concentration were measured at 0 and 48 h.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: The test solutions of chlorine dioxide were prepared by dissolving volumes of test article stock solution directly to the study beakers in order to obtain the requested concentrations taking into account the strength of the stock solution that was checked weekly by RBM.
- Eluate: The dilution water used was the one suggested by ISO 6341-1982
- Differential loading: no data
- Controls: no data
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): not applicable
- Concentration of vehicle in test medium (stock solution and final test solution): not applicable
- Evidence of undissolved material (e.g. precipitate, surface film, etc): no data

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Strain: no data
- Source: laboratory breeding
- Age at study initiation (mean and range, SD): not more than 24 hours
- Weight at study initiation (mean and range, SD): no data
- Length at study initiation (length definition, mean, range and SD): no data
- Valve height at study initiation, for shell deposition study (mean and range, SD): no data
- Peripheral shell growth removed prior to test initiation: no data
- Method of breeding: with green algae (S. capricornutum)
- Feeding during test: NO

ACCLIMATION
- Acclimation period: no data
- Acclimation conditions (same as test or not):
- Type and amount of food:
- Feeding frequency: 3 times/wk
- Health during acclimation (any mortality observed):

Study design

Test type:

no data

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

no data

Test conditions

Hardness:

251 mg/L of CaCO3

Test temperature:

20 °C

pH:

7.1 - 7.5

Dissolved oxygen:

8.0 - 8.7 mg/L

Salinity:

not applicable

Nominal and measured concentrations:

Nominal concentrations: 0.018, 0.032, 0.056, 0.100,0.180 mg/L

Measured concentrations (at t = 0 h): 0, 0.04, 0.06, 0.09 and 0.11 mg/L
Measured concentrations (at t = 48 h): Not determined, 0.02, 0.04, 0.05 and 0.09 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: glass vials
- Type (delete if not applicable): open
- Material, size, headspace, fill volume: no data
- Aeration: no data
- Type of flow-through (e.g. peristaltic or proportional diluter): not applicable
- Renewal rate of test solution (frequency/flow rate): not applicable
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- No. of vessels per vehicle control (replicates):not applicable
- Biomass loading rate: no data

OTHER TEST CONDITIONS
- Adjustment of pH: no data
- Photoperiod: 16:8
- Light intensity: no data

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 1.778
- Justification for using less concentrations than requested by guideline: not applicable 
- Range finding study
- Test concentrations: 0.018, 0.032, 0.056, 0.1, and 0.18 mg/L of chlorine dioxide (nominal concentrations)
- Results used to determine the conditions for the definitive study: no data

Reference substance (positive control):

no

Results and discussion

Effect concentrationsopen allclose all

Effect concentrations 1

Duration:

24 h

Endpoint:

EC50

Effect conc.:

0.076 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

act. ingr.

Basis for effect:

mobility

Remarks (e.g. 95% CL):

95% confidence limits of 0.068 – 0.086 mg/L

Effect concentrations 2

Duration:

48 h

Endpoint:

EC50

Effect conc.:

0.063 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

act. ingr.

Basis for effect:

mobility

Remarks (e.g. 95% CL):

95% confidence limits of 0.048 – 0.084 mg/L

Details on results:

The study was performed taking into account the actual content of the stock solution of chlorine dioxide. The toxicity values can therefore be expressed both as referring to the 100% ClO2 and to the solution at the nominal concentration of 0.2%. The calculated EC50 values of 100% ClO2 at 24 h and 48 h were 0.076 and 0.063 mg/L respectively corresponding to 0.038 and 0.032 g/L of 0.2% solution being 1 g/L its density.

Results with reference substance:

Not applicable

Reported statistics and error estimates:

The 24 h EC50 was 0.076 mg/L with 95% confidence limits of 0.068 – 0.086 mg/L.
The 48 h EC50 was 0.063 mg/L with 95% confidence limits of 0.048 – 0.084 mg/L.

Any other information on results incl. tables:

Table A7_4_1_2(1)-5:        Immobilisation data

Initial measured Concentration (mg/L)	Treated Animals	Immobilized Daphnia			Oxygen (mg/l) 48 h	pH 48 h	Temperature (°C) 48 h
		24 h	48 h	Total %
0.0	20	0	0	0	8.2	7.3	20
0.02	20	0	4	20	8.7	7.3	20
0.04	20	1	6	30	8.5	7.5	20
0.06	20	5	9	45	8.1	7.4	20
0.09	20	9	11	55	8.2	7.3	20
0.11	20	20	20	100	NS	NS	NS

NS = Not stated

Table A7_4_1_2(1)-6:        Effect data

	EC501	95 % c.l.	EC01	EC1001
24 h [mg/l]	0.076 (n)	0.068 – 0.086
48 h [mg/l]	0.063 (n)	0.048 – 0.084	0.02	0.11

1 based on nominal (n) concentrations

Applicant's summary and conclusion

Conclusions:

The 48 h EC50 was 0.063 mg/L.

Executive summary:

Daphnia magna were exposed to chlorine dioxide for 48 hours in an acute immobilization test, under GLP and following C.2 EEC Guideline. No animals were immobilized in the control group. EC50(48h) = 0.063 mg/L of 100% ClO2, i.e. 0.032 g/L of 0.2% ClO2 solution being 1 g/L its density.

Validity criteria fulfilled:

no

Remarks:

No reference substance was tested