(benzothiazol-2-ylthio)acetic acid

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:

2001-01-08 to 2001-01-12

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2001

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

(benzothiazol-2-ylthio)acetic acid

EC Number:

228-565-0

EC Name:

(benzothiazol-2-ylthio)acetic acid

Cas Number:

6295-57-4

Molecular formula:

C9H7NO2S2

IUPAC Name:

2-(1,3-benzothiazol-2-ylsulfanyl)acetic acid

Constituent 2

Reference substance name:

Water

EC Number:

231-791-2

EC Name:

Water

Cas Number:

7732-18-5

Molecular formula:

H2O

IUPAC Name:

water

Test material form:

other: Light paste

Details on test material:

Chemical name: 2-Benzothiazolylthio acetic acid (50%)
CAS RN 6295-57-4
Appearance: Light paste

Sampling and analysis

Analytical monitoring:

yes

Test solutions

Vehicle:

no

Test organisms

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST SYSTEM
Brachydanio rerio (Zebra fish)
Gnathostoma, Pisces, Osteichthyes, Teleostei, Clupeiformes,Cyprinidae

Reason for the selection of the test system
According to the guideline Brachydanio rerio is suitable for this kind of study.

Origin
AQUARIUM AM AEGI, Breite Straße 14, D- 30159 Hannover
All fish used in the test originated from the same delivery of the supplier.

Holding
Holding was performed at the test facility at 23 ± 2°C and diffuse light (0.1-10 µmol/m2s, natural photoperiod). The water was changed at least once per week. The dissolved oxygen concentration was more than 80 % of the air saturation value. Only Zebra fish with at least 12 days of acclimatisation and mortality < 5 % within the last 7 days before the study starts were used in the test. No disease treatments were administered throughout holding.

Feeding
Food was provided 3 times per week. The amount of food was 4% of the fish body weight per feeding day. The test fish were not fed 24 h before the test was started.

Food
Trouvit 40 I 2; MILKIVIT, D-86666 Burgheim

Average body length at the test start: 2.57 cm Average body weight at the test start: 0.2 g

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Test conditions

Hardness:

40-180 mg CaCO3/L

Test temperature:

23 ± 2°C

pH:

6-8

Nominal and measured concentrations:

6.25- 12.5- 25- 50 - 100 mg/L (nominal concentrations)
3.125 - 6.25 - 12.5 - 50 mg/L (active)

Details on test conditions:

TEST METHOD
A static test was performed with one application at the test initiation.

WATER
Tap water of local origin was used for holding. The water was filtered on activated charcoal and aerated for at least 24 h to remove chlorine.
Nominal water parameters:
Total hardness: 40 - 180 mg CaC03/L
pH-value: 6.0 - 8.0
The water is analysed once a year ace. to German tap water regulations.

Dispersion Treatment
The test medium was mixed with a laboratory blender (20000rpm, 1 min).

Test vessel
15 L Glass-aquaria loosely covered by glass tops were used.

Test volume
The test volume was 10 L per vessel.

Aeration
Gentle aeration was provided.

Number of test fish
7 Zebra fish were used per test concentration and control.

Loading, length of fish
Fish density in the tanks was less than 1 g fish per liter test solution.

Replicates
One replicate per test concentration and control.

Introduction of fish
Fish were added to test chambers within 30 min after addition of the test item to the dilution water. Fish were introduced randomly to individual replicates.

Feeding of test fish
The fish were not fed during the test.

Water temperature
23 ± 2 °C

Dissolved oxygenconcentration
Not less than 60 % of air saturation value.

Light intensity
0.1- 10 µmol/m2· s

Photoperiod
A natural photoperiod occured during the test.

Reference substance (positive control):

no

Remarks:

No reference item is recommended for this test according to the guideline.

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

12.5 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Effect concentrations 2

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

6.25 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Effect concentrations 3

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

29 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Effect concentrations 4

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

14.5 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Effect concentrations 5

Duration:

96 h

Dose descriptor:

LC100

Effect conc.:

50 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Effect concentrations 6

Duration:

96 h

Dose descriptor:

LC100

Effect conc.:

25 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Details on results:

CONTROL
7 fish in dilution water (without test item) were tested under the same test conditions as the test replicates.

COURSE OF THE STUDY
Based on the results of a preliminary range finding test, the study was performed with 5 concentration levels ranged from 6.25 to 100 mg/L in a geometrical series with a dilution factor of 2.
One control with water (without test item) was tested under the same conditions as the test group.
7 fish were tested per test item concentration and control. The test fish were not fed during the test.
After 2, 24, 48, 72 and 96 h mortality and behaviour of the test fish was observed.

Results with reference substance (positive control):

No reference item is recommended for this test according to the guideline.

Any other information on results incl. tables

Sublethal observations / clinical signs:

Observations in the Test Vessels

			Test duration [h]
Concentration (nominal) [mg/L]	Concentration (active) [mg/L]	Effect	2	24	48	72	96
100	50	(E)	7/7	-	-	-	-
50	25	(E)	-	6/7	1/1	-	-
		(2.5)	-	1/7	-	-	-
		(2.4)	7/7	-	-	-	-
25	12.5	(E)	-	-	-	-	1/7
		(1)	7/7	7/7	7/7	7/7	6/7
12.5	6.25	(1)	7/7	7/7	7/7	7/7	7/7
6.25	3.125	(1)	7/7	7/7	7/7	7/7	7/7
Control	Control	(1)	7/7	7/7	7/7	7/7	7/7

The number in brackets correspond to the following observation:

(1) = Normal behaviour

(2.4) = Slow escape reflex

(2.5) = No escape reflex

(E) = Exitus lethalis

Cumulative Mortality in [%] in the Test Vessels

		Test duration [h]
Concentration (nominal) [mg/L]	Concentration (active) [mg/L]	2	24	48	72	96
100	50	100	100	100	100	100
50	25	0	86	100	100	100
25	12.5	0	0	0	0	14
12.5	6.25	0	0	0	0	0
6.25	3.125	0	0	0	0	0
Control	Control	0	0	0	0	0

LC values

Test duration [h]	LC50 (active) [mg/L]
2	35.5
24	21.5
48	17.5
72	17.5
96	14.5

LC100 = 25 mg/L (a.i.)

LC0 = 6.25 mg/L (a.i.)

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

In this study the test substance was found to be toxic to Zebra fish after 96 h at nominal concentrations of 25 mg/L and greater. The nominal LC50 (96 h) was 29 (26- 33) mg/L, the NOEC after 96 h was 12.5 mg/L.

Based on active ingredient the test substance was found to be toxic to Zebra fish after 96 h at concentrations of 12.5 mg/L and greater. The LC50 (96 h) was 14.5 mg/L, the NOEC after 96 h was 6.25 mg/L.

Executive summary:

The toxicity of the registration substance to fish (Zebra fish) was determined according to the principles of OECD 203 (adopted July 17, 1992) and EEC Directive 92/69/EEC Method C.1 (December, 1992) at Dr.U.Noack-Laboratorien in 31157 Sarstedt, Germany from 2001-01-08 to 2001-01-12.

The study was conducted under static conditions with nominal concentrations of 6.25- 12.5-25-50- 100 mg/L corresponding to 3.125 – 6.25 – 12.5 – 25 – 50 mg/L. Duration of the test was 96 h. 7 test organisms were exposed to all test concentrations and control. Environmental conditions were determined to be within the acceptable limits. The test item showed sedimentation at test initiation. From 24 h up to test end the test item was clearly dissolved.

All effect concentrations are based on nominal concentrations of the test item. DOC-analysis was carried out at test start from the control and test levels 25 - 50 - 100 mg/L.

The LC50 (96 h) was 14.5 mg/L, the NOEC after 96 h was 6.25 mg/L.