Carbamic acid, N,N'-methylenebis(4,1-cyclohexanediyl)bis-, C,C'-dibutyl ester

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:

2003-12-09- to 2003-12-11

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2004

Report date:

2004

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

4,4'-Methylenebis(N-butoxycarbonylcyclohexanamine)

EC Number:

619-422-7

Cas Number:

99305-42-7

Molecular formula:

C23 H42 N2 O4

IUPAC Name:

4,4'-Methylenebis(N-butoxycarbonylcyclohexanamine)

Details on test material:

- Test substance:: 4,4'-Methylenebis(N-butoxycarbonylcyclohexanamine) of Degussa AG
- Batch 4/032, purity approximately 95 % determined 04-Nov-2003
- White solid

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

MONITORING OF TEST SUBSTANCE CONCENTRATION: Analysis of samples at start and end of study

Test solutions

Vehicle:

no

Details on test solutions:

STOCK AND TEST SOLUTION AND THEIR PREPARATION
- Dispersion: Weighing of test substance, mixing with water,  homogenization with Ultra-Turax, stirring for approx. 24 hours  (magnetic), filtration 
(0.45 µm pore size)
- Vehicle, solvent: None

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISMS
- Strain: Daphnia magna, clone 5
- Source/supplier: Aventis Pharma Deutschland GmbH, ProTox (inhouse)
- Breeding method: 100 ml beakers with 70 ml test water (Elendt, M4), one  daphnid per culture vessel, maximum age used for breeding 42 days,  
monitoring of repdoduction rate and state of health daily except weekends
- Age: < 24 hours
- Feeding: Three times a week with Desmodesmus subspicatus at a level of  0.2 mg carbon / day for each animal
- Feeding during test: No

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Test conditions

Test temperature:

- 21.0 - 21.3 °C

pH:

7.8-8.1

Dissolved oxygen:

8.7-9.1 mg/L

Nominal and measured concentrations:

0 mg/l, 100 mg/l (nominal)

Details on test conditions:

DILUTION WATER
- Source: Prepared from demineralized water according to Elendt (M4) at  least 24 hours before use and aerated until saturation
- Hardness: 2.5 mmol Ca2+ + Mg2+ / l
- Ca/Mg ratio: 80.1 / 12.2 [mg/l]
- Na/K ratio: 19.8 / 3.2 [mg/l]

TEST SYSTEM
- Renewal of test solution: No
- Exposure vessel type: 250 ml beakers filled with 200 ml test solution
- Number of replicates, individuals per replicate: 2 replicates with 10  individuals each l
- Adjustment of pH: No
- Photoperiod: 16 hours/day (fluorescent tubes)

TEST PARAMETER: Immobility

SAMPLING: Inspections after 24 and 48 hours with stimulation of passive  daphnids and removal of immobile animals

Reference substance (positive control):

not specified

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

48 h

Dose descriptor:

EC0

Effect conc.:

>= 0.024 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 2

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 0.024 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Effect data (Immobilisation): No immobility was observed in both test and 
control groups.
- EC50 (Daphnia magna, 48 h) > 100 mg/l (nominal) and 0.024 mg/l (analytical)

Results with reference substance (positive control):

- no data available

Any other information on results incl. tables

Analytical results: 
- Nominal/measured concentrations: Measured concentrations were always in 

a range 20-27 µg/L (mean 24 µg/l), corresponding to 0.020-0.027% (mean 0.024%) 

of nominal, i.e. the solubility was far below the nominal concentration.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

No toxic effects on Daphnia magna could be observed up to the solubility limit of the test substance. Thus the EC50 is >0.024 mg/L

Executive summary:

The acute effects of H12MDU on Daphnia magna were evaluated in a static 48h-limit test according to EU method C.2 and OECD TGD 202. H12MDU was tested at a nominal concentration of 100 mg/L. The analytical monitoring demonstrated that the test substance was soluble up to a concentration of 0.024 mg/L (mean value). Thus the EC50 was determined as >0.024 mg/L.

The study was assessed as "reliable without restrictions".