Sodium chlorite

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

The test substance could not be monitored in the test solutions due to background interference. 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.

Qualifier:

according to guideline

Guideline:

EPA OPP 72-1 (Fish Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

Sampling:Dissolved oxygen, pH, salinity, and temperature were measured daily in each test chamber that contained live animals. The test temperature in one test vessel was recorded continuously during the test.
Monitoring of TS concentration:No, the test substance was not monitored throughout the test as background interference prevented it.

Vehicle:

not specified

Test organisms (species):

Cyprinodon variegatus

Test type:

flow-through

Water media type:

saltwater

Limit test:

no

Total exposure duration:

96 h

Test temperature:

22.7 - 23 °C

pH:

7.6 - 8.2

Dissolved oxygen:

7.0 - 7.8 mg/L

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)

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

60 other: mg sodium chlorite/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

105 other: mg sodium chlorite/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95 % confidence interval of 90 to 150 mg/L

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

78 other: mg clorite/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

60 other: mg sodium chlorite/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

45 other: mg chlorite/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

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).

Sublethal observations / clinical signs:

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

Validity criteria fulfilled:

yes

Remarks:

(mortality in control was 0%; constant conditions were maintained; the dissolved oxygen concentration was within the acceptable range; the concentrations were maintained using a flow-through system).

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:

The aim of this study was to investigate the short-term toxicity to fish produced by the test material.

The test procedure used was the EPA OPP 72-1 (Fish Acute Toxicity Test).

The result was as follows:

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).

Description of key information

Key study. The test procedure used was the EPA OPP 72-1 (Fish Acute Toxicity Test).

The result was as follows:

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).

Key value for chemical safety assessment

Marine water fish

Marine water fish

Effect concentration:

105 mg/L