N,N-dimethyldodecanamide

Toxicity to soil microorganisms

Administrative data

Endpoint:

toxicity to soil microorganisms

Type of information:

experimental study

Adequacy of study:

disregarded due to major methodological deficiencies

Study period:

December 1979

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

other: Study neither conducted according to internationally accepted guideline nor to GLP

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1979

Report date:

1979

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: Method described by Wright et al., 1979b

Deviations:

no

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

N,N-dimethyldodecanamide

EC Number:

221-117-5

EC Name:

N,N-dimethyldodecanamide

Cas Number:

3007-53-2

Molecular formula:

C14H29NO

IUPAC Name:

N,N-dimethyldodecanamide

Details on test material:

- Name of the test substance: N,N-dimethyldodecanamide
- Analytical purity: 95 % (10 % emulsifiable concentrates in 85:5 ethanol)
- Composition of test material, percentage of components: 10 % emulsifiable concentrates in 85:5 ethanol

Sampling and analysis

Analytical monitoring:

no

Details on sampling:

No concentrations were measured.

Test substrate

Vehicle:

yes

Details on preparation and application of test substrate:

- APPLICATION OF TEST SUBSTANCE
- Application of the test substance: Three “tea bags” each containing 20 to 25 adults or nymphal mites were dipped in the solutions for 30 seconds each, then hung on a drying rack.

Test organisms

Test organisms (inoculum):

other: Psoroptes spp

Study design

Total exposure duration:

24 h

Test conditions

Test temperature:

No data

Details on test conditions:

TEST SYSTEM
- Test solutions: Testing serial dilutions of a 0.1% solution to obtain 100 % mortality of the microorganisms.
- Test container: Tea-bags
- Test organisms: Psoroptes cunilis and Psoropte Ovilis.
- Source of the test organisms: Psoroptes cuniculis came from the ears of infested laboratory –maintained rabbits and Psoroptes ovilis came from the backs of infeted cattle.
- No. of replicates per concentration: 3
- Number of the organisms per vessels: 20- 25
- Test performance: Three „tea-bag“ each conbtaining 20 to 25 adult or nymphal mites, were dipped in the solutions for 30 seconds each, then hung on drying rack, The bags were cut open 24 hours postdipping. Mites were rated dead or alive with the aid of a dissecting microscope. (Wright and Riner, 1979b)

EFFECT PARAMETERS MEASURED : Mortality of the microorganisms after 24 hours

VEHICLE CONTROL PERFORMED: no

RANGE-FINDING STUDY
- Test concentrations: 0.001 % and 0.005 %

Nominal and measured concentrations:

- Nominal concentrations: 0.001 % and 0.005 %
- Measured concentration: No concentrations were measured.

Reference substance (positive control):

yes

Remarks:

Toxaphene

Results and discussion

Effect concentrations

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 0.001 - < 0.005 other: %

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: mortality

Remarks on result:

other: 95 % CL not determined

Details on results:

The EC50 of the test substance was determined to be in a range between 0.001 and 0.005 %.

Results with reference substance (positive control):

The EC100 of the reference substance was determined to be 0.001 %.

Reported statistics and error estimates:

Percent mortality was corrected for mortality of the control by Abbott´s formula.

Applicant's summary and conclusion

Validity criteria fulfilled:

not applicable

Conclusions:

The toxic effects of the test substance on Psoroptes spp. (P. ovis and P.cuniculi) after an exposure of 24 hours was determined according to the method described by Wright et al., 1979b. The EC50 of the test substance was determined to be in a arrange between 0.001% and 0.005 %.

Executive summary:

The objective of this study according to method described by Wright et al., 1979b was to determine the toxic effects of the test substance on the Psoroptes spp. (P. ovis and P.cuniculi) after short-term exposure of 24 hours, compared with the blank control. The test was performed in nominal concentrations of 0 (control), 0.001 % and 0.005 % without correction of the purity. No concentrations were measured. A reference substance Toxaphene was used as positive control. The EC50 value of for the reference substance Toxaphene was determined to be greater than 0.001 % and the EC50 of the test substance was determined to be in a arrange between 0.001% and 0.005 %.