2-(6-methoxybenzofuran-2-yl)-1,3-dimethyl-5-(methylsulphonyl)1H-benzimidazolium acetate

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

other: Internal method "Method A-11, Acute Fish Toxicity"

Version / remarks:

Equivalent to OECD Guideline 203

Principles of method if other than guideline:

At testing laboratory, acute fish toxicity testing was performed according to published methods, which were adapted and standardized for the specific needs of the company, well before Test Guidelines for these methods were established by the OECD beginning 1981. The method is comparable to today’s standard testing procedure published by the OECD within Guideline for Testing of Chemicals 203.

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

Leuciscus idus

Details on test organisms:

TEST ORGANISM
- Common name: golden orfe.
- Age at study initiation: about 12 months.
- Length at study initiation: 3 - 4 cm
- Weight at study initiation: 1.5 - 2.5 g

ACCLIMATION
- Acclimation period: minimum 12 days at 10-13 °C
- Feeding frequency during acclimation: daily, with TETRA MIN, flocks, Dr. U.Baersch GmbH.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test temperature:

12 °C

pH:

8.1 - 8.3

Nominal and measured concentrations:

100, 200 and 1000 mg/l

Details on test conditions:

TEST SYSTEM
- Test vessel: full-glass basins, 17 liters basis (36x23x26 cm) tempered (cold-room).
- Material, size, headspace, fill volume: 15 liters.
- No. of organisms per cocnentration: 8 fish.
- No. of vessels per concentration: 1 replicate.
- No. of vessels per control: 1 replicate.

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: according to ISO guidelines.

OTHER TEST CONDITIONS
- pH: testing water were kept at a pH between 6 and 8.5. In case of deviations, pH needs to be adjusted with NaOH or HCl solution.
- Photoperiod: 12 h day/12 h night.

EFFECT PARAMETERS MEASURED
LC50, described as TL50.

TEST CONCENTRATIONS
- Test concentrations: 100 mg/l

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

1 000 mg/L

Nominal / measured:

not specified

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

LC0 (48h): 200 mg/l
LC100 (48h) > 1000 mg/l

Sublethal observations / clinical signs:

Cocnentration (mg/l)	Survival animals		pH
	24 hrs	48 hrs
100	8	8	8.1
200	8	8	8.3
1000	6	4	8.3

Conclusions:

LC50 (48h): 1000 mg/l

Executive summary:

The acute fish toxicity of the substance was assessed in a study conducted acccording to the internal method " Method A-11, Acute Fish toxicity", which is equivalent to OECD Guideline 203. Three groups, of 8 trouts each, were exposed to test concentrations of 100, 200 and 1000 mg/l for 48 hours.

4 out of 8 fish were found dead at the end of 48 hours observation period at the concentration of 1000 mg/l; while no mortality was observed with the concentration of 100 and 200 mg/l. Hence, the LC50 (described as TL50) was determined to be 1000 mg/l.

Conclusion

LC50 (48h): 1000 mg/l

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

other: Internal method "Method A-11, Acute Fish Toxicity"

Version / remarks:

Equivalent to OECD Guideline 203

Principles of method if other than guideline:

At testing laboratory, acute fish toxicity testing was performed according to published methods, which were adapted and standardized for the specific needs of the company, well before Test Guidelines for these methods were established by the OECD beginning 1981. The method is comparable to today’s standard testing procedure published by the OECD within Guideline for Testing of Chemicals 203.

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

yes

Remarks:

acetone

Details on test solutions:

Acetone at 0.6 %

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: rainbow trout.
- Supplier: P. Hohler, 4314 Zeiningen.
- Age at study initiation: about 4-6 months.
- Length at study initiation: 4 - 8 cm
- Weight at study initiation: 3 - 6 g

ACCLIMATION
- Acclimation period: minimum 12 days at 10-13 °C
- Feeding frequency during acclimation: daily, with TETRA MIN, flocks, Dr. U.Baersch GmbH.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test temperature:

12 °C

pH:

7.3 - 7.5

Nominal and measured concentrations:

100, 200 and 1000 mg/l

Details on test conditions:

TEST SYSTEM
- Test vessel: full-glass basins, 17 liters basis (36x23x26 cm) tempered (cold-room).
- Material, size, headspace, fill volume: 15 liters for trout.
- No. of organisms per cocnentration: 8 fish.
- No. of vessels per concentration: 1 replicate.
- No. of vessels per control: 1 replicate.

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: according to ISO guidelines.

OTHER TEST CONDITIONS
- pH: testing water were kept at a pH between 6 and 8.5. In case of deviations, pH needs to be adjusted with NaOH or HCl solution.
- Photoperiod: 12 h day/12 h night.

EFFECT PARAMETERS MEASURED
LC50, described as TL50.

TEST CONCENTRATIONS
- Test concentrations: 100 mg/l

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

not specified

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

No mortality was observed throughout the duration of the observation period.

Sublethal observations / clinical signs:

Cocnentration (mg/l)	Survival animals		pH
	24 hrs	48 hrs
100	8	8	7.4
200	8	8	7.3
1000	8	8	7.5

Conclusions:

LC50 (48h) > 1000 mg/l

Executive summary:

The acute fish toxicity of the substance was assessed in a study conducted acccording to the internal method " Method A-11, Acute Fish toxicity", which is equivalent to OECD Guideline 203. Three groups, of 8 trouts each, were exposed to test concentrations of 100, 200 and 1000 mg/l for 48 hours. No mortality was observed throughout the duration of the observation period. Hence, the LC50 (described as TL50) was determined to be higher than 1000 mg/l.

Conclusion

LC50 (48h) > 1000 mg/l

Description of key information

Not harmful/toxic to fish for short-term exposure (LC50 (48h) > 100 mg/l of test item)

Additional information

Several studies, conducted on batches characterized by different purity degrees of Fluorescent Brightener 363, investigating short-term toxicity potential in different species of fish (including rainbow trout, zebrafish and goldorfe) are available.

Almost all the experiments here reported were performed according to published methods, which were adapted and standardized for the specific needs of the sponsor company, well before Test Guidelines for these methods were established by the OECD beginning 1981; the method is comparable to current standard testing procedure published by the OECD within Guideline for Testing of Chemicals 203.

In the two studies conducted on test batches at highest purity degree among all the experiments, three groups, of 8 trouts each, were exposed to the concentrations of 100, 200 and 1000 mg/l over a period of 48 hours. In one experiment no mortality was observed throughout the duration of the observation period; in the other one, 4 out of 8 fish were found dead at the end of 48 hours observation period at the concentration of 1000 mg/l; while no mortality was observed with the concentration of 100 and 200 mg/l.

Except in two cases in which LC50 at 24 and 48 hours was identified to be 2080 and 520 mg/l, respectively, in all the other experiments the LC50 at 48 hours was identified to be higher than 1000 mg/l.

Thus, taken into consideration the batch characteristics and the most of the results, the LC50 value, re-calculated taken into consideration the purity degree and the substance content, resulted to be higher than 150 mg/l and possibly around 300 mg/l. Only in one case the LC50 recalculated resulted to be lower than 100 mg/l (i.e. ca 80 mg/l); however, since the most of the values are consistent, the LC50 at 48 hours can be reasonably concluded stated to be higher than 100 mg/l of Fluorescent Brightener 363.

Although in none of the experiments available the actual tested concentrations were measured, the substance is expected to be stable over the entire study period due to their physicochemical properties and nature of the substance. Fluorescent Brightener 363 is very water soluble and is completely dissociated in water; it neither readily degraded/transformed, nor photo/water/etc reactive.