Ethyl chloroformate

Genetic toxicity: in vitro

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

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: GLp Guideline study in accordance with OECD TG 471. However only 4 strains testedoever

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1988

Report date:

1988

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

4 strains only

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Ethyl chloroformate

EC Number:

208-778-5

EC Name:

Ethyl chloroformate

Cas Number:

541-41-3

Molecular formula:

C3H5ClO2

IUPAC Name:

ethyl chlorocarbonate

Details on test material:

- Name of test material (as cited in study report): c hloroformic acid ethyl ester
- Analytical purity: 98.0%.
- Physical state: liquid

Method

Target gene:

Salmonella Typhimurium: (his-)

Species / strain

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Additional strain / cell type characteristics:

not applicable

Metabolic activation:

with and without

Metabolic activation system:

S-9 mix including Aroclor induced male Sprague-Dawley rat liver 9000 g supernatant

Test concentrations with justification for top dose:

0.0005 - 5.0 microliters/plate (TA1535);
0.0005 - 0.4 microliters/plate (TA98, TA100, TA1537)

Vehicle / solvent:

- Vehicle(s)/solvent used:ethanol
- Justification for choice of solvent/vehicle: soulability,

Controls

Controls 1

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

Remarks:

ethanol

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene (2-AA)

Remarks:

with metabolic activation TA 1535, TA 1537, TA 98 and TA 100

Controls 2

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

Remarks:

ethanol

Positive controls:

yes

Positive control substance:

other: N- methyl - N '- nitro - N - nitroso - guanidine ( MNNG)

Remarks:

TA 1535; TA 100 without metabolic activation

Controls 3

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

Remarks:

Ethanol

Positive controls:

yes

Positive control substance:

9-aminoacridine

Remarks:

TA 1537 without metabolic activation

Controls 4

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

Remarks:

Ethanol

Positive controls:

yes

Positive control substance:

other: 4-nitro-o-phenylendiamine

Remarks:

TA 98 without metabolic activation

Details on test system and experimental conditions:

METHOD OF APPLICATION: preincubation
DURATION
- Preincubation period: 20 min
- Exposure duration: 48 hours
- Expression time (cells in growth medium): 48 hours

SELECTION AGENT (mutation assays): histidine

NUMBER OF REPLICATIONS: 3

DETERMINATION OF CYTOTOXICITY
- Method: relative total growth

Evaluation criteria:

A substance was considered mutagenic if it caused a doubling in the spontaneous mutation rate, and the effect was dose-dependent and repro-
ducible.

Statistics:

no data

Results and discussion

Test results

Species / strain:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

> = 0.015 microliters/plate (without S-9 mix); > = 0.2 microliters/plate (with S-9 mix)

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

There was no mutagenic effect of test material in the presence or absence of S-9. The test material was completely soluble in ethanol.

In the absence of S-9, the average numbers of mutants in controls in strains TA98, TA100, TA1535 (all experiments), and TA1537 were 23, 149, 16-18, and 10, respectively. The average numbers of mutants in treated strains TA98, TA100, TA1535 and TA1537 ranged from 23-27, 154-164, 0-18, and 3-9, respectively.

In the presence of S-9, the average numbers of mutants in controls in strains TA98, TA100, TA1535 (all experiments) and TA1537 were 33, 134, 17-25, and 10, respectively. The average numbers of mutants in treated strains TA98, TA100, TA1535, and TA1537 with S-9 ranged from 29-36, 134-137, 0-23, and 6-11, respectively.

The positive control material DIMCA caused a dose-dependent increase in mutants in strain TA1535 in the absence or presence of S-9.  With strain TA100, a weakly positive effect of DIMCA was found, with a maximum increase in the number of mutants at 0.5 microliters/plate of a factor of 2.3 (without S-9 mix) or 2.0 (with S-9 mix).  All other positive controls induced at least a 4-fold increase in mutants.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

Ethylchloroformiate was neagtive in an OECD TG 471 preincubation study.