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

Long-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2012-02-21 to 2012-03-14

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study according to OECD study 2011 (2004)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

Version / remarks:

(1998)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

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

IUPAC Name:

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

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

- Molecular formula (if other than submission substance): C19H20N4*1 H20- Molecular weight (if other than submission substance):322.4 - Storage condition of test material: in tighly closed container at ambient temperature

Sampling and analysis

Analytical monitoring:

yes

Test solutions

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)- Method: The test was performed using concentrations of 0.04, 0.08, 0.16,0.25.0.38, 0.56 mg/L (diluting factor 8, 16, 32, 50, 76, 112).- Controls: yes- Chemical name of vehicle (organic solvent, emulsifier or dispersant): acetone- Concentration of vehicle in test medium (stock solution and final test solution(s) including control(s)): 112 µL/L used in control groups

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM- Common name: Daphnia Magna- Strain/clone: breed of 62 D.M.- Source: Chinese Center of Desease Control and Prevention (Bejing, China) - Age of parental stock (mean and range, SD): aged less than 24 h at the start of the test, individuals of later than the first batch is used- Feeding during test: yes- Food type: Dry powder of Scenedsmus sp., - Amount:0.15 mg Carbon /day/Daphnia magna- Frequency: daily-Light: 16 hours light

Study design

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Test conditions

Hardness:

no data

Test temperature:

within a range: 19.4 - 21.0 °C

pH:

within the range of pH 7.25-7.49

Dissolved oxygen:

within a range of 7.89- 8.49 mg/L

Salinity:

not applicable

Nominal and measured concentrations:

Nominal: 0.04, 0.08, 0.16,0.25.0.38, 0.56 mg/L Average acutal conc.: 0.072; 0.116; 0.187; 0.270; 0.506; 0.631 mg/L

Details on test conditions:

TEST SYSTEM10 animals individually held at each test concentration and at least 10 animals individually held in the control series- Test vessel: 100mL- Aeration: no- Renewal rate of test solution (frequency/flow rate): every 48 h during the test and time of change was rcorded- No. of organisms per vessel: 1 Fo of less than 24 h- No. of vessels per concentration (replicates): 10- No. of vessels per vehicle control (replicates): 10- Biomass loading rate: 1 F0/100 mLTEST MEDIUM / WATER PARAMETERSM4 MediumOTHER TEST CONDITIONS- Adjustment of pH: no- Photoperiod: 16 hours light, 8 hours dark- Light intensity:of 1800 - 2300 LUXEFFECT PARAMETERS MEASURED (with observation intervals if applicable) : birth of F1 time and number; mortality of Fo; temperature of the dilution; dissovled oxygen and pH values; content of test substance in dilutonVEHICLE CONTROL PERFORMED: yesRANGE-FINDING STUDYnot data

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

21 d

Dose descriptor:

LOEC

Effect conc.:

0.08 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Effect concentrations 2

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

0.04 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Effect concentrations 3

Duration:

21 d

Dose descriptor:

other: MATC , max allowable toxicant concentration, China

Effect conc.:

0.057 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Reported statistics and error estimates:

Significance of difference in terms of biological effect corresponding to treatments (including controls) is compared by using data processing software DPS© following the route of “Experimental statistics - Completely randomized design - One-way ANOVA - Duncan Method”

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The NOEC and LOEC were found to be 0.04 mg/L and 0.08 mg/L, respectively, and the MATC was calculated to be 0.057 mg/L