Benzimidazole

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

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Justification for type of information:

data from handbook.

Qualifier:

according to guideline

Guideline:

other: as mentioned below

Principles of method if other than guideline:

The toxicity to fish study has been performed to evaluate the acute effects of chemical Benzimidazole in 24-hrs.

GLP compliance:

not specified

Specific details on test material used for the study:

- IUPAC name: 1H-benzimidazole
- Name of test material (as cited in study report):Benzimidazole
- Molecular formula: C7H6N2
- Molecular weight: 118.1384 g/mol
- Substance type: Organic
- Physical state: Solid

Analytical monitoring:

not specified

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Chemical name of vehicle (organic solvent, emulsifier or dispersant):2-Propanone or Ethanol
- Concentration of vehicle in test medium (stock solution and final test solution(s) or suspension(s) including control(s)):5 PPT

Test organisms (species):

other: Salmo gairdnerii

Details on test organisms:

- LIFE STAGE:Fingerling
- Length at study initiation (length definition, mean, range and SD): <= 4 in

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

24 h

Test temperature:

12.77 deg.C

pH:

7.5 to 8.2

Dissolved oxygen:

8.6 to 13.7 ppm

Details on test conditions:

No data

Reference substance (positive control):

not specified

Key result

Duration:

24 h

Dose descriptor:

NOEC

Effect conc.:

5 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Validity criteria fulfilled:

not specified

Conclusions:

In short term fish toxicity study, no effects were observed for 1H-benzimidazole at dose concentration 5 mg/l on fish species Salmo gairdreii thus, the NOEC value is 5 mg/l for 24 hrs exposure period.

Executive summary:

Short term toxicity study on fish species Salmo gairdreii, Lepomis macrochirus and Petromyzon marinus was carried out for 24 hrs. Test was performed under static condition and fresh water medium (lake water) and pH maintained as 7.5 to 8.2, test temperature 12.77 deg.C and dissolved oxygen as 8.6 to 13.7 ppm. No effects were observed at dose concentration 5 mg/l on the test fish species Salmo gairdreii, Lepomis macrochirus and Petromyzon marinus thus the NOEC value for test chemical was consider to be 5 mg/l for 24 hrs exposure period.

Description of key information

Short term toxicity study on fish species Salmo gairdreii, Lepomis macrochirus and Petromyzon marinus was carried out for 24 hrs. Test was performed under static condition and fresh water medium (lake water) and pH maintained as 7.5 to 8.2, test temperature 12.77 deg.C and dissolved oxygen as 8.6 to 13.7 ppm. No effects were observed at dose concentration 5 mg/l on the test fish species Salmo gairdreii, Lepomis macrochirus and Petromyzon marinus thus the NOEC value for test chemical was consider to be 5 mg/l for 24 hrs exposure period.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

100 mg/L

Additional information

Based on the experimental data from various database for the target chemical study have been reviewed to determine the mode of action of Benzimidazole (CAS No. 51 -17 -2) on the mortality rate and behavior of fish. The studies are as mentioned below:

In the first key study from handbook or collection of data, short term toxicity study on fish species Salmo gairdreii, Lepomis macrochirus and Petromyzon marinus was carried out for 24 hrs. Test was performed under static condition and fresh water medium (lake water) and pH maintained as 7.5 to 8.2, test temperature 12.77 deg.C and dissolved oxygen as 8.6 to 13.7 ppm. No effects were observed at dose concentration 5 mg/l on the test fish species Salmo gairdreii, Lepomis macrochirus and Petromyzon marinus thus the NOEC value for test chemical was consider to be 5 mg/l for 24 hrs exposure period.

 

First study was supported by another experimental studies. Short term toxicity study on fish species Petromyzon marinus was carried out for 24 hrs. Test was performed under static condition and fresh water medium (lake water) and pH maintained as 7.5 to 8.2, test temperature 12.77 deg.C and dissolved oxygen as 8.6 to 13.7 ppm. No effects were observed at dose concentration 5 mg/l on the test fish species Salmo gairdreii, Lepomis macrochirus and Petromyzon marinus thus for test chemical, the NOEC value was consider to be 5 mg/l for 24 hrs exposure period.

 

Similarly another study was designed to access the toxic effects of the test compound on the Zebra fish (Danio rerio). Test was conducted in compliance with the OECD guideline 203. The test substance was soluble in water. Therefore, the test solution was prepared by dissolving 1 g of the test substance in 4 liters of potable water (passed through reverse osmosis system) with continuous stirring for achieving test concentrations of 100 mg/L, respectively. Test conducted at limit test concentration 100 mg/l and Zebra fishes were exposed to this concentration for 96 hours. Test animal was collected from Orange City Aquarium, Sitabuldi, Nagpur, MS (India). 8 fishes exposed to the test concentration. Aeration in test vessels was provided 1 day before the start of experiment. After the exposure of chemical (mortality, visible symptoms, pH, Temperature, dissolved oxygen content) were recorded after 24 hours, 48 hours, 72 hours and 96 hours of the start of the experiment. Based on nominal concentrations, experimental median lethal Concentrations [LC-50 (96 h)] for test chemical on Zebra fish (Danio rerio) was determined to be > 100 mg/L by observing the mortality. Thus based on LC50 it can be concluded that the chemical was nontoxic and can be consider to be not classified as per the CLP classification criteria.

 

Thus on the basis of overall studies chemicalBenzimidazole (CAS No. 51 -17 -2)was consider as nontoxic to fishes and not classified as per the CLP classification criteria.