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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro gene mutation study in mammalian cells
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
2010
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Cross-reference
Reason / purpose for cross-reference:
read-across source
Reference
Endpoint:
genetic toxicity in vitro, other
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
other information
Justification for type of information:
Justification is provided in the separate statement.
Reason / purpose for cross-reference:
assessment report
Reason / purpose for cross-reference:
assessment report
Reason / purpose for cross-reference:
assessment report
Reason / purpose for cross-reference:
assessment report
Reason / purpose for cross-reference:
assessment report
Conclusions:
The in-vitro genotoxicity of the registration substance sodium N-lauroyl glutamate is derived based on the read-across to Sodium N-cocoyl glutamate and Sodium N-cocoyl glycinate. No significant in-vitro genotoxicity can be reliably derived.
Executive summary:

The in-vitro genotoxicity of the registration substance, sodium N-lauroyl glutamate, is derived based on the read-across to sodium N-cocoyl glutamate and sodium N-cocoyl glycinate.

The registration substance and the read-across sources are amides of fatty acids and amino acids and can be characterized as "N-fatty acyl amino acids", of which endogeous occurence and metabolism are known. Based on the comparable chemical structure, comparable phys-chem data and expected comparable metabolism, these compound are likely exhibit comparable toxicity profiles.

 

The genotoxicity of sodium N-cocoyl glutamte was investigated in Ames test (OECD 471). No mutagenic activity was found.

The genotoxicity of sodium N-cocoyl glycinate was investigated in Ames test (OECD 471) and in mouse lymphoma assay (OECD 476). The results obtained in these studies are indicative of low mutagenic potential. Further, two chromosome aberrations studies are available reporting positive response. However, these studies were re-evaluated according to the currently accepted Guideline OECD 473 (adopted in 2016) by the registrant and the data are evaluated as indicative of no significant clastogenicity.

 

Likewise, the registration substance, sodium N-lauroyl glutamate is considered as of no significant genotoxic activity.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2010
Report date:
2010

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to guideline
Guideline:
OECD Guideline 476 (In Vitro Mammalian Cell Gene Mutation Test)
Deviations:
no
Qualifier:
according to guideline
Guideline:
EU Method B.17 (Mutagenicity - In Vitro Mammalian Cell Gene Mutation Test)
Deviations:
no
Principles of method if other than guideline:
first experiment: 4 hours treatment with and without metabolic activation
second experiment: 24 hours treatment without metabolic activation, 4 hours treatment with metabolic activation
GLP compliance:
yes (incl. QA statement)
Type of assay:
mammalian cell gene mutation assay

Test material

Constituent 1
Reference substance name:
Sodium cocoyl glycinate (SCG) [INCI]
IUPAC Name:
Sodium cocoyl glycinate (SCG) [INCI]
Details on test material:
Stability of Test Item: Stable under storage conditions
Stability of Test Item Dilution: Unknown in PEG 300; excluded from the statement of compliance.
Storage Conditions: At room temperature (range of 20 ± 5 °C, provided by Harlan Laboratories Ltd.), light protected.
Safety Precautions: Routine hygienic procedures were used to ensure the health and safety of the personnel.
Description: Colorless solid

Method

Target gene:
Thymidine Kinase Locus
Species / strain
Species / strain / cell type:
mouse lymphoma L5178Y cells
Details on mammalian cell type (if applicable):
- Type and identity of media: RPMI
- Periodically checked for Mycoplasma contamination: yes
- Periodically checked for karyotype stability: yes
- Periodically "cleansed" against high spontaneous background: yes
Additional strain / cell type characteristics:
other: Clone 3.7.2C
Metabolic activation:
with and without
Metabolic activation system:
Phenobarbital/Beta-Naphtoflavone induced Rat liver S9
Test concentrations with justification for top dose:
Experiment I:
without S9 mix: 5.9; 11.8; 23.5; 47.0; 94.0; 141.0 µg/mL
with S9 mix: 11.8; 23.5; 47.0; 94.0; 188.0; 282.0 µg/mL
Experiment II:
without S9 mix: 11.8; 23.5; 47.0; 94.0; 188.0; 282.0 µg/mL
with S9 mix: 8.8; 17.5; 35.0; 70.0; 105.0; 140.0 µg/mL
Following the expression phase of 48 hours the cultures at the maximum concentration of both main experiments were not continued due to exceedingly strong toxic effects.
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: deionised water
- Justification for choice of solvent/vehicle: solubility properties
Controlsopen allclose all
Untreated negative controls:
no
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
methylmethanesulfonate
Remarks:
without metabolic activation
Untreated negative controls:
no
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
cyclophosphamide
Remarks:
with metabolic activation
Details on test system and experimental conditions:
METHOD OF APPLICATION: in medium

DURATION
- Exposure duration: 4 hours with and without metabolic activation in experiment 1, 24 hours without metaoblic activation in experiment and 4 hours with metabolic activation in experiment 2
- Expression time (cells in growth medium): 48 hours
- Selection time (if incubation with a selection agent): 10 to 15 days

SELECTION AGENT (mutation assays): RPMI 1640 medium by addition of 5 µg/mL TFT

NUMBER OF REPLICATIONS: 2

NUMBER OF CELLS EVALUATED: >1,5 x 10 exp. 6 cells

DETERMINATION OF CYTOTOXICITY
- Method: relative total growth


Evaluation criteria:
A test item is classified as mutagenic if the induced mutation frequency reproducibly exceeds a threshold of 126 colonies per 10 exp. 6 cells above the
corresponding solvent control or negative control, respectively.
A relevant increase of the mutation frequency should be dose-dependent.
A mutagenic response is considered to be reproducible if it occurs in both parallel cultures.
However, in the evaluation of the test results the historical variability of the mutation rates in negative
and/or vehicle con¬trols and the mutation rates of all negative and/or vehicle controls of this study are taken into consideration.
Results of test groups are generally rejected if the relative total growth, and the cloning efficiency 1 is less than 10 % of the vehicle control
unless the exception criteria specified by the IWGT recommendations are fulfilled.
Whenever a test item is considered mutagenic according to the above mentioned criteria, the ratio of small versus large colonies is used
to differentiate point mutations from clastogenic effects. If the increase of the mutation frequency is accompanied by a reproducible and
dose dependent shift in the ratio of small versus large colonies clastogenic effects are indicated.
Statistics:
Linear regression analysis (least squares) using SYSTAT(R) 11 (SYSTAT Software, Inc., 501, Canal Boulevard, Suite C, Richmond, CA 94804, USA)

Results and discussion

Test results
Species / strain:
mouse lymphoma L5178Y cells
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
cytotoxicity
Vehicle controls validity:
valid
Untreated negative controls validity:
not examined
Positive controls validity:
valid
Additional information on results:
TEST-SPECIFIC CONFOUNDING FACTORS
- Effects of pH: Not effected
- Effects of osmolality: Not increased
- Evaporation from medium: Not examined
- Water solubility: Up to 25 %
- Precipitation: pre-experiment: at 750, 1500, 3000 µg/mL; main experiments: no precipitation occurred
- Other confounding effects: None


RANGE-FINDING/SCREENING STUDIES:
The highest concentration used in the pre-test was chosen with regard to the molecular weight of the test item. Test item concentrations between 23.4 and 3000 µg/mL were used to evaluate toxicity in the presence (4 h treatment) and absence (4 h and 24 h treatment) of metabolic activation.
Strong toxic effects occurred at 187.5 µg/mL and above with and without metabolic activation following 4 and 24 hours of treatment.
The test medium was checked for precipitation at the end of each treatment period (4 or 24 hours) before the test item was removed. Precipitation was observed by the unaided eye at 750 µg/mL and above with and without metabolic activation at both treatment intervals.
The dose range of the main experiments was set according to the data generated in the pre-experiment. The experimental part of the second
experiment with metabolic activation was terminated due to exceedingly severe cytotoxicity and repeated at lower concentrations. In both main
experiments the individual concentrations were generally spaced by a factor of 2.0 in the lower range. A narrower spacing was used at the highest concentrations to cover the cytotoxic range more closely.
To overcome problems with possible deviations in toxicity the main experiments were started with more than four concentrations.


Any other information on results incl. tables

Summary Table
      relative mutant   relative mutant  
  conc. µg S9 total colonies/   total colonies/  
  per mL mix growth 106cells threshold growth 106cells threshold
Column 1 2 3 4 5 6 7 8
Experiment I / 4 h treatment   culture I culture II
Solv. control with water - 100.0 100 226 100.0  71 197
Pos. control with MMS  19.5 -  40.3 292 226  28.4 330 197
Test item   5.9 - 116.4 109 226 100.2  79 197
Test item  11.8 - 102.1  88 226  90.2  81 197
Test item  23.5 - 114.9 101 226  90.3  71 197
Test item  47.0 -  94.7  89 226 104.3  60 197
Test item  94.0 -  22.4 111 226  14.9 123 197
Test item  141.0 - culture was not continued# culture was not continued#
       
Solv. control with water + 100.0  75 201 100.0 115 241
Pos. control with CPA   3.0 +  57.9 185 201  54.0 263 241
Pos. control with CPA   4.5  +   28.2 236 201  28.0 465 241
Test item  11.8  +   85.1  76 201  88.5 103 241
Test item  23.5  +   78.9  90 201  96.3  74 241
Test item  47.0  +   79.7  96 201 102.9  94 241
Test item  94.0  +   81.6  96 201  83.7  86 241
Test item  188.0  +   18.0 124 201  23.3 130 241
Test item  282.0  +  culture was not continued# culture was not continued#
Experiment II / 24 h treatment   culture I culture II
Solv. control with water - 100.0  67 193 100.0 129 255
Pos. control with MMS  13.0 -  20.4 649 193  25.9 697 255
Test item  11.8 -  59.5 117 193  61.8 169 255
Test item  23.5 -  66.8  84 193  74.8  94 255
Test item  47.0 -  64.5  77 193  52.2 128 255
Test item  94.0 -  43.7  69 193  39.1 140 255
Test item  188.0 -  1.6 195 193  1.6 171 255
Test item  282.0 - culture was not continued# culture was not continued#
Experiment II / 4 h treatment   culture I culture II
Solv. control with water + 100.0  70 196 100.0  98 224
Pos. control with CPA   3.0 +  44.6 218 196  26.4 408 224
Pos. control with CPA   4.5 +  22.0 272 196  16.4 378 224
Test item   8.8 +  47.1 163 196  82.9 125 224
Test item  17.5 +  74.4  87 196  77.8 133 224
Test item  35.0 +  48.6  86 196  92.9  95 224
Test item  70.0 +  50.5  99 196  98.6  78 224
Test item  105.0 +  47.4  67 196  81.7  80 224
Test item  140.0 + culture was not continued# culture was not continued#

threshold = number of mutant colonies per 106cells of each solvent control plus 126

#    culture not continued due to exceedingly strong toxic effects

 

Applicant's summary and conclusion

Conclusions:
The genotoxicity of sodium N-cocoyl glycinate was investigated according to the Guideline OECD 476 (MLA). No mutagenic acitivty was found.
Executive summary:

The genotoxicity of sodium N-cocoyl glycinate was investigated according to the Guideline OECD 476 (MLA). In two independent experiments, the mouse lymphoma L5178Y cell cultures were treated with the test item up to the concentrations associated with 20% cell growth reduction with and without metabolic activation. No mutagenic acitivity was found.