Registration Dossier

Administrative data

Endpoint:
in vitro gene mutation study in bacteria
Remarks:
Type of genotoxicity: gene mutation
Type of information:
experimental study
Adequacy of study:
key study
Study period:
July 1994-November 1994
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1994
Report Date:
1995

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
GLP compliance:
yes
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent

Method

Target gene:
no applicable
Species / strain
Species / strain:
other: strains: TA 1535, TA 1537, TA 98, TA 100, TA 102
Metabolic activation:
with and without
Metabolic activation system:
S9 mix from aroclor 1254-induced rat liver (5%)
Test concentrations with justification for top dose:
Toxicity study (24h): 0.075-0.1-0.1-0.25-0.5-1-5
Toxicity study (48h): 0.5-1-5-10-20/0.05-0.075-0.1-0.25-0.5
Genotoxicity study (48h): 0.05-0.075-0.1-0.25-0.5
Controlsopen allclose all
Negative controls:
no
Solvent controls:
no
True negative controls:
no
Positive controls:
yes
Positive control substance:
2-nitrofluorene
sodium azide
mitomycin C
Positive control substance:
other: 9-aminoacridine, with metabolic activation : 2-aminoanthracene and Danthron
Details on test system and conditions:
IUCLID4 Type: Salmonella typhimurium reverse mutation assay

Results and discussion

Test results
Key result
Species / strain:
other: TA1535,TA1537, TA98,TA100, TA 102
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity:
yes
Vehicle controls valid:
yes
Positive controls valid:
yes
Remarks on result:
other:
Remarks:
Migrated from field 'Test system'.
Additional information on results:
see tables attached

Any other information on results incl. tables


Toxicity
After 24-pour and 48-hour treatments:
Highly toxic effect on TA 98 and TA 100 without S-9 mix from
0.5% upwards.

Genotoxicity study
No genotoxic effect whatever the concentration tested with
and without S9 mix, on the five tester strains.

Positive controls induced a marked increase in the revertant
colonies/plate for all strains.

Applicant's summary and conclusion

Conclusions:

Ethylmethylamine was not genotoxic in the Ames test.
Executive summary:

The genotoxic potential of ethylmethylamine was assessed by the Ames test on five Salmonella

typhimurium tester strains: TA1535, TA1537, TA98, TAIOO and TA102, both in the absence and

presence of metabolic activation.

Ethylmethylamine, a liquid volatile compound, was tested as a gas at concentrations (v/v)

ranging from 0.05 to 20%.

In the preliminary toxicity assay performed on TA98 and TAIOO with and without metabolic

activation, ethylmethylamine induced a marked toxic effect from 0.5% upwards after a 48-hour

treatment. In a second toxicity study performed on TA98 and TAlOO without S-9 mix at

concentrations of 0.075, 0.1, 0.25, 0.5, l and 5% with a 24-hour treatment, and at 0.05, 0.075,

0.1, 0.25 and 0_.5% with a 48-hour treatment, ethylmethylamine induced a marked toxic effect

from 0.5% upwards whatever the treatment duration.

Consequently, the 48-hour treatment was retained for the two genotoxicity studies and the

concentrations selected were 0.05, 0.075, 0.1, 0.25 and 0.5%.

A slight toxic effect was observ.ed on His+ revertant colonies, at the concentration of 0.5%,

depending on the tester strain.

Whether in the presence or in the absence of metabolic activation, no increase was observed in

the number of His+ revertant colonies/plate at any of the concentrations tested, on the five

Salmonella typhimurium tester strains during the two geno.toxicity studies.

In conclusion, ethylmethylamine was not genotoxic in the Ames test, with and without metabolic

activation, when tested as a gas.