Urea, reaction products with formaldehyde and glyoxal

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:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP gideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Details on test material:

- Name of test material (as cited in study report): Fixapret CP konz., PBG = 10073662, after Concentration
- Analytical purity: 93.4 %
- Lot/batch No.: 000335MCA0

Method

Species / strain

Species / strain 1

Species / strain / cell type:

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

Species / strain 2

Species / strain / cell type:

E. coli WP2 uvr A

Metabolic activation:

with and without

Metabolic activation system:

S9-Mix prepared from sprague Dawlay rat livers after Aroclor 1254 activation.

Test concentrations with justification for top dose:

0; 22; 110; 550; 2750; 5500 µg/plate (Standard plate test with and without S9 mix)
0; 343.8; 687.5; 1375; 2750; 5500 µg/plate (Preincubation test)

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: water
- Justification for choice of solvent/vehicle: good solubility

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Positive control substance:

other: see details

Details on test system and experimental conditions:

Standard plate test
Test tubes containing 2 ml portions of saft agar kept in a water bath at 45°C, and the remaining companents are added in the following order:
0.1 ml test solution or vehicle
0.1 ml bacterial suspension
0.5 ml S-9 mix (in tests with metabolic activatian) or
0.5 ml phosphate buffer (in tests without metabalic activatian)
After mixing, the samples are poured onto Vogel-Bonner agar plates. After incubation at 37°C for 48 -72 hours in the dark, the bacterial calonies (his+ revertants) are counted.


Preincubation test
0.1 ml test solution or vehicle, 0.1 ml bacterial Suspension and 0.5 ml S-9 mix are incubated at 37°C for the duration of 20 minutes. Subsequently, 2 ml of soft agar is added and, after mixing, the samples are poured onto the agar plates within approx.30 seconds.


Both Tests
In each experiment 3 Test plates per dose per control used. After incubation at 37°C for 48 -72 hours in the dark, the bacterial colonies (his+ revertants) are counted.

Posivite Control:
with S-9 mix: 2.5 µg 2-aminoanthracene (2-AA)(dissolved in DMSO) for the strains TA 100, TA 98, TA 1537and TA 1535
60 µg 2-aminoanthracene (2-AA)(dissolvecl in DMSO) for the strain E. coli WP2 uvrA
without S-9 mix: 5 µg N-methyl-N'-nitro-N-nitroso-guanidine (MNNG) (dissolved in DMSO) for the strains TA 100 and TA 1535
10 µg 4-nitro-o-phenylendiamine (NOPD) (dissolved in DMSO) for the strain TA 98
100 µg 9-aminoacridine (AAC) chloride monohydrate (dissolved in DMSO) for the strain TA 1537
10 µg N-ethyl-N'-nitro-N-nitroso-guanidin (ENNG) (dissolved in DMSO) for the strain E. coli WP2 uvrA

The Titer was determined and in regularly measurements the strain characteristics were checked. Sterility control performed.

Results and discussion

Test results

Test results 1

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

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 2

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

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

SOLUBITITY:

No precipitation on the test item was found.

TOXICITY:

A weak bacteriotoxic effect was occasionally observed depending on the strain and test conditions at 5500 µg/plate.

MUTAGENICITY

A relevant increase in the number of his+ or trp+ revertants was not observed in the standard plate test or in the preincubation test either without S9 mix or after the addition of a metabolizing system.