Guanidinium thiocyanate

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

Study period:

2000-04-10 to 2000-04-29

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Version / remarks:

17 July, 1992

Deviations:

no

GLP compliance:

no

Remarks:

The study described in this report was conducted in accordance with SN EN 45001.

Specific details on test material used for the study:

Batch 1210.9225

Analytical monitoring:

no

Remarks:

Active ingredient (a.i.) content, nominal 100 %

Vehicle:

no

Details on test solutions:

A stock solution of 1600 mg/I in tap water was prepared. From this stock solution the final nominal test concentrations were prepared by dilution with tap water.

Test organisms (species):

Poecilia reticulata

Details on test organisms:

TEST ORGANISM
- Common name: Guppy
- Strain: Poecilia reticulata
- Source: no data
- Age at study initiation (mean and range, SD): no data
- Length at study initiation (length definition, mean, range and SD): 1 -3 cm
- Weight at study initiation (mean and range, SD): no data

ACCLIMATION
- no information

FEEDING DURING TEST
- Food type: Sera micropan, Sera vipan
- Frequency: last fed 24 h before the start

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

total: 17.7 - 31.9 °F

Test temperature:

21 ± 1 °C

pH:

8.3 - 8.7

Dissolved oxygen:

7.0 - 8.0 mg/l

Salinity:

Chloride max. 12.0 mg/l; sulfate max 21.0 mg/L

Conductivity:

510 - 858 µS/cm

Nominal and measured concentrations:

0, 25, 50, 100, 200 and 400 mg/l (nominal)

Details on test conditions:

TEST SYSTEM
- Test vessel: glass aquaria, 1L
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Tap water from Schlieren, aerated

OTHER TEST CONDITIONS
- Photoperiod: 14h, supplied by overhead white fluorescent tubes

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
Mortality, at 24, 48, 72 and 96h

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2

- Range finding study:
Prior to the definitive test a range finding test with concentrations of 1, 10 and 100 mg/I and 3 fish per test vessel was conducted.
2 of 3 fish died at 100 mg/I after 24 h of exposure.
No mortality was observed at 10 and 1 mg/I and in the control after 96 h of exposure.
Based on these data nominal concentrations of 25, 50, 100, 200 and 400 mg/I were chosen for the definitive test

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

ca. 89.1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

In the definitive test all fish died at the nominal concentrations of 400 and 200 mg/I after 24 and 72 h of exposure, respectively.
After 96 h of exposure a total of 1, 1 and 4 of 7 fish were dead at the nominal concentrations of 25, 50 and 100 mg/I, respectively.
No mortality was observed in the control after 96 h of exposure.
Other toxic effects than mortality, e.g. loss of coordination, hypoactivity and swimming on the back, were observed at 200, 100 and 50 mg/I, respectively.

The no-observed-effect concentration (NOEC) was 25 mg/I since the one fish that died is considered not to represent a significant effect as defined by the validity criteria of the test.
100 % mortality (LC100) was observed at the nominal concentration of 200 mg/I after 72 h of exposure.

Reported statistics and error estimates:

The LCso value at 96 h of exposure was calculated from the percentage response (number of dead fish) and the logarithms of the corresponding nominal a.i. concentrations with Microsoft Excel

Sublethal observations / clinical signs:

Incidence of mortality observed

Nominal Concentration mg/l	Number of dead fish observed at different points in time after start of exposure
	2 h	24 h	48 h	72 h	96 h
control 0	0	0	0	0	0
25	0	0	0	1	0
50	0	0	0	0	1
100	0	0	0	3	1
200	0	2	2	3	-*
400	0	7	-*	-*	-*

*All fish died, no further observations

 

 

Nominal concentration (mg/l)	Number of affected fish ^a)	Time of score (h)	body-length (mm)	body-weight (mg)	symptom ^b)
400	7/0	24	21 20 22 20 26 27 19	84 47 85 71 115 128 52	dead, at bottom
200	2/5	24	19 29	37 180	dead, at bottom
200	1/5	24	-	-	loss of orientation
200	2/3	48	22 22	82 95	dead, at bottom
100	1/7	48	-	-	loss of orientation
200	3/0	72	17 24 20	52 132 101	dead, at bottom
100	3/4	72	20 22 16	87 102 37	dead, at bottom
50	2/7	72	-	-	hypoactivity
25	1/6	72	16	41	dead, at bottom
100	1/3	96	22	75	dead, at bottom
50	1/6	96	18	45	dead, at bottom

a)     Number of affected fish number of fish.

b)    e.g. hyper-/hypoactivity, immobility, swimming at the bottom/surface, darkened pigmentation/ discoloring

Validity criteria fulfilled:

yes

Remarks:

All data were in accordance with the criteria of validity described in the referred guidelines for this test.

Conclusions:

Based on these data the nominal lethal concentration (LC5o) of Guanidine thiocyanate to Poecilia reticulata was calculated to be 89.1 mg/l.

Executive summary:

In a 96-h acute toxicity study, guppies (Poecilia reticulate) were exposed to Guanidine thiocyanate at nominal concentrations of 0, 25, 50, 100, 200 and 400 mg/l (nominal) under static conditions.  The 96-h LC50 was 89.1 mg/l nominal. 

No chemical analyses of the test concentrations were conducted, the active ingredient (a.i.) content of the test material is 100 %.

The no-observed-effect concentration (NOEC) was 25 mg/l since the one fish that died is considered not to represent a significant effect as defined by the validity criteria of the test. Sublethal effects like loss of coordination, hypoactivity and swimming on the back, were observed at 200, 100 and 50 mg/l, respectively. 

This toxicity study is classified as acceptable and satisfies the guideline requirement for acute fish toxicity study.

Results Synopsis

Test organism: Guppy (Poecilia reticulate, 1-3 cm) 

Test Type: static 

LC50:  89.1 mg/l nominal

NOEL:  25 mg/l nominal

Endpoint(s) Effected: mortiality

Description of key information

The acute toxicity of Guanidine thiocyanate was tested in a 96-h toxicity test in Poecilia reticulate (Guppy). The 96-h-LC50 was 89.1 mg/l nominal (100 % a.i)

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

LC50

Effect concentration:

89.1 mg/L

Additional information

In a 96-h acute toxicity study, guppies (Poecilia reticulate) were exposed to Guanidine thiocyanate at nominal concentrations of 0, 25, 50, 100, 200 and 400 mg/l (nominal) under static conditions.  The 96-h LC50 was 89.1 mg/l nominal. 

No chemical analyses of the test concentrations were conducted, the active ingredient (a.i.) content of the test material is 100 %.

The no-observed-effect concentration (NOEC) was 25 mg/l since the one fish that died is considered not to represent a significant effect as defined by the validity criteria of the test. Sublethal effects like loss of coordination, hypoactivity and swimming on the back, were observed at 200, 100 and 50 mg/l, respectively. 

This toxicity study is classified as acceptable and satisfies the guideline requirement for acute fish toxicity study.