Didecyldimethylammonium chloride

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

23 Apr, 1990 - 10 May, 1990

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1990

Report date:

1990

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.13/14 (Mutagenicity - Reverse Mutation Test Using Bacteria)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Didecyldimethylammonium chloride

EC Number:

230-525-2

EC Name:

Didecyldimethylammonium chloride

Cas Number:

7173-51-5

Molecular formula:

C22H48N Cl

IUPAC Name:

didecyldimethylammonium chloride

Details on test material:

Test substance: as prescribed by 1.2 as typical marketed susbtance (act: 50%, ipa: 20%, water: 30%)
Composition: ca. 50% Didecyldimethylammonium chloride (CASno.: 7173-51-5) and 20% isopropanol (CASno.: 67-63-0) in water.
Lot number: 93711

Method

Target gene:

rfa – causing partial loss liposaccharide barrier uvrB – mutation in excision repair system
gal – mutation in the galactose metabolism
chl – mutation in nitrate reductase
bio – defective biotin synthesis

Species / strain

Species / strain / cell type:

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

Metabolic activation:

with and without

Metabolic activation system:

S9 mix, routinely prepared from Aroclor 1254 induced (500 mg/kg i.p.) adult male Wistar or Sprague Dawley rats, which were obtained from Charles River Wiga, Sulzfeld, F.R.G.

Test concentrations with justification for top dose:

Dosages: 0, 0.03, 0.1, 0.33, 1.0 or 3.3 µg/plate (active ingredient) without metabolic activation and up to 10.0 ug/plate (active ingredient) in the presence of metabolic activation, based on a preliminary toxicity test in TA 100.

Controls

Controls 1

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Positive controls:

yes

Positive control substance:

sodium azide

Controls 2

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Positive controls:

yes

Positive control substance:

2-nitrofluorene

Controls 3

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene

Controls 4

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Positive controls:

yes

Positive control substance:

9-aminoacridine

Controls 5

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Positive controls:

yes

Positive control substance:

other: daunomycine

Controls 6

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Positive controls:

yes

Positive control substance:

methylmethanesulfonate

Details on test system and experimental conditions:

Type: Ames test
Study Type: Bacterial reverse mutation test
Organism/cell type: S. typhimurium: TA 1535, TA 1537, TA 98, TA 100.
Deficiencies / Proficiencies: rfa – causing partial loss liposaccharide barrier uvrB – mutation in excision repair system
gal – mutation in the galactose metabolism chl – mutation in nitrate reductase bio – defective biotin synthesis
Metabolic activation system: S9 mix, routinely prepared from Aroclor 1254 induced (500 mg/kg i.p.) adult male Wistar or Sprague Dawley rats, which were obtained from Charles River Wiga, Sulzfeld, F.R.G.
Positive control: Sodium azide, 2-nitrofluorene (2-NF), 2-aminoanthracene (2-AA), 9-aminoacridine (9-AC), daunomycine,Methylmethanesulfonate
(MMS)

Results and discussion

Test results

Test results 1

Key result

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

other: 33 µg/plate

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 2

Key result

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

other: 33 µg/plate

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 3

Key result

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

other: 33 µg/plate

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 4

Key result

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

other: 33 µg/plate

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Any other information on results incl. tables

In TA1537, in absence of S9-mix, a slight not dose related increase in number of revertants was observed. As it was
observed in the second experiment only, it was considered not relevant.

None of the other bacterial strains (TA1535, TA98 and TA100), as wel as TA1537 in the first experiment showed a
dose-related, two-fold, increase in the number of revertants in two independently repeated experiments. 
The negative and strain-specific positive control values fell within our laboratory background historical ranges.

Number of revertants in second experiment in TA 1537 without S9-mix:

ConcenTration    number     times 
µg/plate       revertants   control
_____________________________________
0               11 +/-  3     
0.03            17 +/-  3     1.5
0.1             12 +/-  9     1.1
0.33            17 +/-  4     1.5
1.0             27 +/-  3     2.5
3.3             12 +/-  4     1.1
pos control    537 +/-128    48.8

Applicant's summary and conclusion

Conclusions:

Based on the study results, the test substance was considered to be non-mutagenic.

Executive summary:

The test substance was examined for mutagenic activity in an Ames test using the histidine-requiringSalmonella typhimuriummutants TA 1535, TA 1537, TA 98 and TA 100, with and without a liver microsome fraction of Aroclor 1254-induced rats for metabolic activation (S-9 mix). The positive control substances employed were sodium azide, 2-nitrofluorene (2-NF), 2-aminoanthracene (2-AA), 9-aminoacridine (9-AC), daunomycine, methylmethanesulfonate (MMS). In TA1537, in the absence of S9, a slight not dose-related increase in the number of revertants was observed. As this was seen in the second experiment only, it was considered not relevant. None of the other bacterial strains showed a dose-related increase in the number of revertants in two independently repeated experiments. The negative and strain-specific positive control values fell within the laboratory background historical ranges. Based on the study results, the test substance was considered non-mutagenic (Scheres, 1990).