potassium (oxido-NNO-azoxy)cyclohexane; cyclohexylhydroxydiazene 1-oxide, potassium salt; [K-HDO]

Short-term toxicity to fish

Administrative data

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Start of experiment: Apr. 28, 1980

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1980

Report date:

1980

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: DIN 38 412; test procedure with water organisms (group L) general notes on the design, performance and evaluation of biological test procedures (L1) and determination of the effect of constituents of water on fishes - fish test (L15).

Version / remarks:

Draft, January 1979.

Deviations:

not specified

Principles of method if other than guideline:

German standard methods for the examination of water, waste water and sludge; bio-assays (group L); determination of the effect of substances in water on fish, fish-test (L15)

GLP compliance:

no

Remarks:

Test performed prior to the implementation of GLP

Test material

Test material information

Constituent 1

Reference substance name:

Cyclohexylhydroxydiazene 1-oxide, potassium salt

EC Number:

613-953-8

Cas Number:

66603-10-9

Molecular formula:

C6H11KN2O2

IUPAC Name:

Cyclohexylhydroxydiazene 1-oxide, potassium salt

Test material form:

liquid

Details on test material:

Xyligen 30F is a 30% aqueous solution of K-HDO.

Specific details on test material used for the study:

N-cyclohexyldiazeniumdioxy potassium
30% technical active substance, 70% water
Purity: technical
Solubility in water: readily soluble
Lot/Batch Nr.: Test substance Nr.: 79/571

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Test organisms

Test organisms (species):

Leuciscus idus

Details on test organisms:

TEST ORGANISM
- Common name: golden orfe
- Strain: Leuciscus idus L.
- Source: P. Eggers, Hohenwestedt, Germany
- Length at study initiation: Body length: 6.4 cm
- Weight at study initiation: Body weight: 1.9 g

ACCLIMATION
- Acclimation period: 3 days
- Type and amount of food during acclimation: "Holstenstolz A complete trout feed" type 34 Wilhelm Stroeh Jun. KG, Hobbersdorf-Luebeck, FRG; ad libitum
- Health during acclimation (any mortality observed): No mortality observed

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

No

Test conditions

Hardness:

See table below

Test temperature:

20°C ± 1°C

pH:

8 ± 0.1

Dissolved oxygen:

> 8 mg/L

Salinity:

The following concentrations of salts were added to the completely demineralized water:
344 mg/L CaSO4 • 2H2O
124 mg/L MgSO4 • 7H2O
70 mg/L NaHCO3
3 mg/l KCL

Nominal and measured concentrations:

No measurement of the test substance. However, KHDO is hydrolytically stable at pH 7 and 9. Furthermore, in all other aquatic tests the nominal concentrations were confirmed within analytical measurements.

Details on test conditions:

TEST SYSTEM
- Test vessel: 10 litres test water in glass aquaria (30 cm x 22 cm x 24 cm) (for 10 fish)
- Aeration: Continuous aeration with oil-free air
- Renewal rate of test solution (frequency/flow rate): No renewal of test solution
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 10
- No. of vessels per control (replicates): 10

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Test water: prepared from completely demineralized water; pre-purification over an active charcoal filter, demineralization over an "Aquadem" type 42 DF cartridge for complete demineralization supplied by Wassertechnische Anlagen (WTA), Cologne, FRG
The following concentrations of salts were added:
344 mg/L CaSO4 • 2H2O
124 mg/L MgSO4 • 7H2O
70 mg/L NaHCO3
3 mg/l KCL
- Culture medium different from test medium: yes

OTHER TEST CONDITIONS
- Adjustment of pH: no details given in the study report
- Photoperiod: no details given in the study report
- Light intensity: no details given in the study report

EFFECT PARAMETERS MEASURED (with observation intervals if applicable):
Determination of the mortality after: 4h, 24h, 48h, 72h, 96 h
Determination or calculation of the median Lethal concentration (LC50), the LC5 and the LC95 by probit analysis after: 4h, 24h, 48h, 96 h
Signs after 4h and 48h

TEST CONCENTRATIONS
- Test concentrations: 46.4, 68.1, 100, 147, 215, 316, 464, 681 mg/L

Reference substance (positive control):

yes

Remarks:

Chloroacetamide

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

4 h

Dose descriptor:

LC50

Effect conc.:

> 680 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other:

Remarks:

tumbling

Effect concentrations 2

Key result

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

ca. 680 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other:

Remarks:

tumbling

Effect concentrations 3

Key result

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

340 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other:

Remarks:

tumbling

Effect concentrations 4

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

171 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other:

Remarks:

tumbling

Effect concentrations 5

Key result

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Details on results:

- Behavioural abnormalities: tumbling
- Mortality of control: Chloroacetamide positive control: LC50 about 27 mg/L (at 48 h); this result corresponds to normal sensitivity.

Results with reference substance (positive control):

Chloroacetamide positive control: LC50 about 27 mg/L (at 48 h)
This result corresponds to normal sensitivity.
Results are valid.

Reported statistics and error estimates:

See table below

Any other information on results incl. tables

Sublethal observations / clinical signs:

Mortality data:

	Number
Test-Substance Concentration (nominal) [mg/L]	24 h	48 h	72 h	96 h
0	0	0	0	0
46.4	0	0	0	0
68.1	0	0	0	0
100	0	0	0	0
147	0	2	2	2
215	0	1	5	9
316	0	3	9	10
464	3	10	10	10
681	2	10	10	10
Temperature [°C]				20
pH				7.7-7.9
Oxygen [mg/l]				7.8-8.3

Results of probit analysis:

		95 % confidence limits
	Concentration	lower	upper
LC50	171.0	147.5	198.6
LC5	128.0	80.6	148.2
LC95	228.5	197.3	364.2

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Golden orfe test: LC50 (96h): 171 mg/L

Executive summary:

The acute toxicity test performed with 30 % K-HDO technical on Leuciscus idus L. (Golden orfe) produced the following results:

LC 50 after:

4 h	greater than	680 mg/l (10 % level of significance)
24 h	about	680 mg/l
48 h	about	340 mg/l (figure from intrapolation)
96 h	equal to	171 mg/l (slope factor = 1.19)

No effect level: 100mg/l
Highest concentration tested without mortality: 100 mg/l