Chlorine dioxide-Dossier: Sodium Chlorite Short-term toxicity to fish.010

http://www.qsartoolbox.org/de/web/guest/registration-dossier/-/registered-dossier/15450/6/2/2/?documentUUID=cae9e5e6-0490-4829-bb8d-8fa5dfa1fdc0

Chlorine dioxide-Dossier: Sodium Chlorite

Short-term toxicity to fish.010

Administrative data

Purpose flag:

key study

Study result type:

read-across from supporting substance (structural analogue or surrogate)

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

The test substance could not be monitored in test solutions due to background interferences. However, the method allowed accurate determination of the stock solution concentrations in deionised water. As a flow-through system was used, the nominals are considered acceptable estimates of the actual concentration.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1991

Materials and methods

Test guideline

Qualifier:

according to

Guideline:

EPA OPP 72-1 (Fish Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes (incl. certificate)

Test materials

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

no

Test material identityopen allclose all

Test material identity 1

Identifier:

CAS number

Identity:

7758-19-2

Test material identity 2

Identifier:

EC number

Identity:

231-836-6

Test material identity 3

Identifier:

IUPAC name

Identity:

sodium chlorite

Details on test material:

Lot/Batch number: 09-M, PAL M-033, used for screening toxicity test; 75-A/PAL A-300, used for the definitive test
Purity: 80%
Further relevant properties: white powder

Analytical monitoring:

yes

Details on sampling:

Sampling: Dissolved oxygen, pH, salinity, and temperature were measured daily in each test chamber that contained live animals. Test temperature in one test vessel was recorded continuously during the test.

Monitoring of TS concentration: No, test substance was not monitored throughout the test as background interference prevented it.

Vehicle:

no data

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Initial 300 000 mg/l of stock solution was prepared by combining 750 g of test substance and adjusting the volume to 2 L with deionized water in a glass class A volumetric flask. The stock solution was mixed and transferred to the diluter.Appropriate amounts of the stock solution was mixed and transferred to the diluter (1.5 ml of test substance was combined with 3000 ml of water during each diluter cycle).
- Eluate: unfiltered seawater from Atlantic ocean at Envriosystems in Hampton, New Hampshire. salinity of 11-17 ppt.

Test organisms

Test organisms (species):

Cyprinodon variegatus

Details on test organisms:

TEST ORGANISM
- Common name: Sheephead minnows
- Strain: no data
- Source: Aquatic Research Organisms Division or Resources Analysts, Inc., Hampton, New Hampshire
- Age at study initiation (mean and range, SD): no data
- Length at study initiation (length definition, mean, range and SD): no data
- Weight at study initiation (mean and range, SD): no data
- Method of breeding: no data
- Feeding during test: Yes
- Food type: commercial fish food (EnviroSystems lot number TM02)
- Amount: no data
- Frequency: once or twice daily

ACCLIMATION
- Acclimation period: yes
- Acclimation conditions (same as test or not): 100% dilution water under flow trought conditions.
- Type and amount of food: no data
- Feeding frequency: no data
- Health during acclimation (any mortality observed): Fish were free of apparent sickness, injuries, and abnormalities at the beginning of the test.

Study design

Test type:

flow-through

Water media type:

saltwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

no data

Test conditions

Test temperature:

22.7 - 23 °C

pH:

7.6 - 8.2

Dissolved oxygen:

7.0 - 7.8 mg/L

Salinity:

17 ppt

Nominal and measured concentrations:

Nominal concentrations of the active ingredient were 0 mg/L (control), 22.5, 37.5, 60, 90 and 150 mg sodium chlorite/L. Test concentrations were adjusted for the purity of the test substance.
(These doses are equivalent to 0, 17, 28, 45, 67 and 112 mg chlorite/L)

Details on test conditions:

TEST SYSTEM
- Test vessel: glass class A. Aquaria of 19.6 L , that contained 15 L of test solution.
- Material, size, headspace, fill volume: 15 L of test solution
- Aeration: not required
- Type of flow-through (e.g. peristaltic or proportional diluter):
- Renewal rate of test solution (frequency/flow rate):
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2
- No. of vessels per vehicle control (replicates): not applicable
- Biomass loading rate: no data

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Seawater collected at Hampton, New Hampshire
- Total organic carbon: no data
- Particulate matter: no data
- Metals: no data
- Pesticides: no data
- Chlorine: no data
- Alkalinity: no data
- Ca/mg ratio: no data
- Conductivity: no data
- Culture medium different from test medium: no data
- Intervals of water quality measurement: no data

OTHER TEST CONDITIONS
- Adjustment of pH: no data
- Photoperiod: 16:8
- Light intensity: 12 µEs/m²

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : no data

TEST CONCENTRATIONS
- Spacing factor for test concentrations: no data
- Justification for using less concentrations than requested by guideline: no data
- Range finding study no data
- Test concentrations: no data
- 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

Effect concentrations 2

Effect concentrations 3

Effect concentrations 4

Effect concentrations 5

Details on results:

At a nominal concentration of 150 mg/L some fish were lethargic at 48 h. Exposure of Sheepshead minnows to the test substance resulted in a 96 h LC50 of 105 mg/L sodium chlorite with a 95 % confidence interval of 90 to 150 mg/L (equivalent to 78 mg chlorite/L). The 96 h NOEC was 60 mg/L sodium chlorite (equivalent to 45 mg chlorite/L).

Any other information on results incl. tables:

Table A7_4_1_1(2)-5:        Mortality data

Test-Substance Concentration (nominal) [mg sodium chlorite/L]	Mortality
	Number     24 h          48 h          72 h          96 h				Percentage     24 h         48 h          72 h           96 h
0 (control)	0	0	0	0	0	0	0	0
	0	0	0	0	0	0	0	0
22.5	0	0	0	0	0	0	0	0
	0	0	0	0	0	0	0	0
32.7	0	0	0	1	0	0	0	5
	0	0	0	0	0	0	0	0
60	0	0	0	1	0	0	0	5
	0	0	0	0	0	0	0	0
90	0	0	1	2	0	0	5	10
	0	1	1	2	0	5	5	10
150	0	9	10	10	0	90	100	100
	0	8	10	10	0	80	100	100

Table A7_4_1_1(2)-6:        Sub-lethal effect data

Test-Substance Concentration (nominal) [mg sodium chlorite/L]	Lethargy
	Number     24 h          48 h          72 h          96 h				Percentage     24 h         48 h          72 h           96 h
0 (control)	0	0	0	0	0	0	0	0
	0	0	0	0	0	0	0	0
22.5	0	0	0	0	0	0	0	0
	0	0	0	0	0	0	0	0
32.7	0	0	0	0	0	0	0	0
	0	0	0	0	0	0	0	0
60	0	0	0	0	0	0	0	0
	0	0	0	0	0	0	0	0
90	0	0	0	0	0	0	0	0
	0	0	0	0	0	0	0	0
150	0	1	-	-	0	5	-	-
	0	2	-	-	0	10	-	-

Table A7_4_1_1(2)-7:        Effect data

	96 h [mg/l]1	95 % c. l. [mg/l]
LC0	60	Not specified
LC50	105 (n)	90 to 150
LC100	Not specified	Not specified

1 indicate effect data are based on nominal (n) concentrations

Applicant's summary and conclusion

Conclusions:

96 h LC50 = 105 mg/L sodium chlorite with a 95 % confidence interval of 90 to 150 mg/L (equivalent to 78 mg chlorite/L).

Executive summary:

Acute toxicity test of sodium chlorite on sheepshead minnows was performed following EPA OPP 72-1 Guideline. The test was performed under flow-through conditions with 5 concentrations of test substance and a dilution water control at 22°C. All animals were in good condition at the beginning of the study. Exposure of fish to sodium chlorite resulted in an EC50 (96h) = 105 mg/l of sodium chlorite, and a NOEC (96h) = 60 mg/l.