Acetamide, N-(2-amino-4,5,6,7-tetrahydro-6-benzothiazolyl)-, hydrobromide (1:1)

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

June 2004 to August 2004

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2004

Report date:

2004

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

yes

Remarks:

deviations stated as uncritical

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

N-(2-Methyl-4,5,6,7-tetrahydro-benzothiazol-6-yl)-acetamide hydrobromide

EC Number:

600-588-4

Cas Number:

104617-50-7

Molecular formula:

C9 H13 O N3 S x HBr

IUPAC Name:

N-(2-Methyl-4,5,6,7-tetrahydro-benzothiazol-6-yl)-acetamide hydrobromide

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source: not mentioned
- Purity: 96.8 % (HPLC-MS)


STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: dark at room temperature

Sampling and analysis

Analytical monitoring:

no

Details on sampling:

Sample storage conditions before analysis: The test item was stored in a closed glass vessel dry at room temperature.

Test solutions

Vehicle:

not specified

Details on test solutions:

Main study:
- A stock solution containing 100 mg/L test item in dilution water was prepared.
Date: June 30th -July 2nd 2004
Treatment : 100 mg/L
Duration: 48 hours
Observation time : 24 and 48 hours
Temperature : 20 ± 2 °C
Vessels: glass beakers, nominal volume 50 ml, tall shape
Feeding : none
Lighting : none
Replicates : four vessels, each containing 20 ml test solution and 5 Daphnia
Control: four vessels, each containing 20 ml dilution water and 5 Daphnia

Reference study:
- A stock solution containing 250 mg K2Cr201 /I in deionized water was diluted with dilution water to give a series of concentrations between 0.625 and 3.0 mg/L.
Date: June 23 rd - 24th 2004
Concentrations : 3.0 I 2.5 I 2.0 I 1.5 / 1.25 / 1.0 / 0.625 mg/L
Duration : 24 hours
Observation time : 24 hours
Temperature : 20 ± 2 °C
Vessels: glass beakers, nominal volume 50 ml, tall shape
Feeding : none
Lighting :none
Replicates : four vessels, each containing 20 ml test solution and 5 Daphnia
Control: four vessels, each containing 20 ml dilution water and 5 Daphnia

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

Species : Daphnia magna
Variety : STRAUS
Strain : Berlin
Sex : female
Age : between O and 24 hours
Origin : Umweltbundesamt Berlin
Arrival of Strain : July 10th 2003

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Remarks on exposure duration:

Animals were put into the respective test solution.
The test vessels were left to stand for 48 hours

Post exposure observation period:

24 and 48 hours

Test conditions

Test temperature:

Tempera­ture range was 22.0 - 23.0 °C

pH:

The pH values in the test media and the control ranged from 7.2 to 8.2.

Dissolved oxygen:

The concentra­tion of dissolved oxygen stayed above 8.2 mg/L or 91 % throughout the test.

Nominal and measured concentrations:

The measured concentration after 48 hours was 102.0 % and 102.9 % of the nominal concentration and the start concentration, respectively. Therefore, the determination of the biological results was based on the nominal concentration.

Details on test conditions:

Daphnia magna is bred in the LAUS GmbH throughout the year. The animals are kept for the use in toxicity tests. They multiply by parthenogenesis, thus being genetically identical. The holding is performed similar to the method described in EN ISO 6341, fol­lowing SOP 115 002 01

Vessels : glass beakers, nominal volume 2 I
Medium : M4-Medium (recipe of ELENDT)
Food: cold water fish food Tetra Aminin®, finely ground, suspended in M4-Medium and boiled for three seconds green algae (Desmodesmus subspicata)

Medium renewal : twice a week
Photo period : 16/8 hours, using neon tubes
Temperature: 20 ± 2 °C

Potassium dichromate K2Cr201 (GAS No. 7778-50-9) was used as reference item.

Drinking water with an enrichment of certain minerals (as de­manded in the guidelines) is used in the test.

After preparation, the dilution water is aerated, and the pH is adjusted to 7.8 ± 0.2. The resulting hardness is 2.50 mmol/L alkaline-earth metal cations, corresponding to 250 mg CaCOs/L.

The beakers used are made of glass. They were cleaned by scrubbing with detergent, multiple rinsing with drinking water, rinsing with diluted hydrochloric acid and finally rins­ ing with deionized water. They were then dried at 105 °C.

Instruments and Devices:
thermometer glass LAUS No.: 20020912-07
scales MT AB 184 SA and Sartorius 1403
adjustable pipettes with one-way tips (for volumina 0.1 - 1 ml) LAUS No.: 16
glass measuring cylinders
glass measuring flasks
pH-meter 340i wtw
oxygen meter Oxical 538 wtw

Usage and, if applicable, calibration following the corresponding SOP in the current edi­tion.

Reference substance (positive control):

yes

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

24 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 2

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 3

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 4

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

Immobilities
- In the treatment and the control, none of the daphnia died or showed any signs of ab­normal behaviour throughout the test

The validity criteria were met. For the estimation of the EC50 of the reference item, the fit showed sufficient statistical correspondence of the data with the dose-response­ equation.
The analytical determinations of the test item showed very good correlation between nominal and measured concentrations and very good·recovery rates. Therefore, the test item SND 919 Precursor 1 (Thiazol) can be stated as stable under the test conditions.
Therefore, the determination of the results was based on the nominal concentrations.

Results with reference substance (positive control):

Validity:
- The 24h-EC50i of K2Cr2O1 should lie between 0.6 and 2.4 mg/L according to EN ISO 6341 and between 0.6 and 1.7 mg/L according to the OECD draft guideline 201.
The 24h-EC50i of K2Cr2O1 was determined as 1.5 mg/I. Immobilization in the controls may not exceed 1O %.
- Immobilization in the controls was O %.
- The concentration of dissolved oxygen at the end of the test must be at least 60% of the saturation value .
The lowest concentration of dissolved oxygen at the end of the test was 8.2 mg/I. 100% saturation equals 9.05 mg/I at 20 °C, giving 91 % oxygen saturation for the value measured.


The validity criteria were met. For the estimation of the EC50 of the reference item, the fit showed sufficient statistical correspondence of the data with the dose-response­ equation.
The analytical determinations of the test item showed very good correlation between nominal and measured concentrations and very good·recovery rates. Therefore, the test item SND 919 Precursor 1 (Thiazol) can be stated as stable under the test conditions.
Therefore, the determination of the results was based on the nominal concentrations.

Reported statistics and error estimates:

The estimation of the EC50 of the reference item was accomplished using the software Origin™. The calculated values for r (0.9736) resp. r2 (0.9479)
The data were evaluated using sigmoidal fit.

Equation: yskalaM =A+ B * xskala(X)

Biological results:
Parameter Value 95%-confidence interval
NOEL 24h 0.625 mg/L N.D
24h EC50i 1.5 mg/L 1.3 - 2.3 mg/L
24h EC100i 2.5 mg/L N.D

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The following test results could be determined for the test item SND 919 Precursor 1 (Thiazol) (species: Daphnia magna):
24h and 48h NOEC = 100 mg/L
24h and 48h EC50i > 100 mg/L