2-Propyl-4-methyl-6-(1-methylbenzimidazol-2-yl)benzimidazole

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

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1997

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

440-240-7

EC Name:

-

Cas Number:

1282554-35-1

Molecular formula:

C19 H20 N4

IUPAC Name:

2-Propyl-4-methyl-6-(1-methylbenzimidazol-2-yl)benzimidazole

Results and discussion

Effect concentrations

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

>= 10 - <= 12 mg/L

Basis for effect:

mobility

Applicant's summary and conclusion

Conclusions:

Acute Toxicity Study in Daphnia maqna with BIBR 227lBIMBIM .The study procedures described in this report were based on the EEC directive 92/69, Part C.2. Acute toxicity for Daphnia and the OECDguideline No. 202: "Daphnia sp., Acute Immobilisation Test", Adopted April 4, 1984.BIBR 227lBIMBIM is a solid which was hardly soluble in water. The water solubility of BIBR 227lBIMBIM was determined to be 6.0 X 10-2 mg/L at 17.5+ 0.5"C (NOTOX Project 199597). After a range-finding test, a limit test was performed with daphnids exposed to a filtrate (ca. 5 pm) of a supersaturated solution of 100 mg/L prepared without any additive. The test consisted of two vessels per group containing 10 daphnids per vessel. Analysis showed that the exposure concentration was 12 mg/L in a sample taken from the filtrate at the start of the test and 10 mg/L in a sample taken at the end of the test. BIBR 2271BIMBIM induced no effects in Daphnia magna exposed to a homogenous and stable dispersion of 10-12 mg/L, which exceeded the maximum solubility of BIBR 227lBIMBIM. Hence, the EC50 was greater than 10 mg/L and, owing to the low solubility of the test substance, concentrations acutely toxic to crustaceans are not expected to occur in the aquatic environment after any kind of spill or discharge.