Ricinoleyl monomaleate triglyceride

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

Negative response in an AMES test and a Chromosome Aberration Test in Cultured Human Peripheral Blood Lymphocytes.

Link to relevant study records

Reference

Endpoint:

in vitro cytogenicity / chromosome aberration study in mammalian cells

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

experimental study

Adequacy of study:

key study

Study period:

17 August to 2 November 1999

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study according to international guidelines.

Qualifier:

according to guideline

Guideline:

OECD Guideline 473 (In Vitro Mammalian Chromosome Aberration Test)

GLP compliance:

yes

Type of assay:

in vitro mammalian chromosome aberration test

Species / strain / cell type:

lymphocytes: human

Details on mammalian cell type (if applicable):

Blood collected from healthy male non-smokers. Blood was stored refrigerated and pooled prior to use. Whole blood cultures were established in sterile disposable centrifuge tubes by placing 0.4 ml heparinised blood into 9.0 mL Heps-buffered RPMI medium containing 20% (v/v) foetal calf serum and 50 µg/mL Gentamycin. Phytohaemagglutinin (PHA, reagent grade) was included at a concentraion of approximately 10 µg/mL of culture to stimulate the lymphocytes to divide. Blood cultures wee incubated for approx. 48 hours at 37 dC and rocked continuously.

Additional strain / cell type characteristics:

not applicable

Metabolic activation:

with and without

Metabolic activation system:

Araclor induced rat S-9

Test concentrations with justification for top dose:

Experiment 1: 4.844, 6.921, 9.887, 14.12, 20.18, 28.82, 41.18, 58.82, 84.04, 120.1, 171.5, 245, 350, 500 µg/mL
Experiment 2: 37.54, 50.06, 66.74, 88.99, 118.7, 158.2, 210.9, 281.3, 375, 500 µg/mL

Vehicle / solvent:

Dimethylsulfoxide (DMSO)

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

True negative controls:

no

Positive controls:

yes

Positive control substance:

4-nitroquinoline-N-oxide

cyclophosphamide

Details on test system and experimental conditions:

Exposure:
Experiment 1 (with or without metabolic activation): 3 h exposure + 17 h
Experiment 2 : with metabolic activation: 3 h exposure + 17 h recovery, without metabolic activation: 20 h exposure + 0 h recovery.
Harvesting:
Approx. 2 h prior to harvest addition of colchicine to arrest dividing cells in metaphase. Then centrifugation at 300 g for 10 minutes. Removal of supernatant end resuspending in 4 mL hypotonic (0.075 M) KCl and incubated for 15 min to allow cell swelling. Then fixing of cells using ice-cold methanol/glacial acetic acid (3:1 v/v). Subsequently, centrifugation of fixative + cells, and repeating this procedure until the cell pellets were clean.
Preparation of metaphase spreads:
Lymphocytes were kept for at least 12 h in fixative before preparation of slides. Chromosome spreading was enhanced by adding 45% (v/v) aqueous acetic acid and additonally by flaming the slides if necessary.After drying the slides they were stained in 4% (v/v) filtered Giemsa stain in pH 6.8 buffer. Then the slides were rinsed, dried and mounted with coverslips.
Cytogenetic analysis:
Slides were examined "blind" for mitotic index (MI) or percentage of cells in mitosis based on at least 1000 cells counted per dose. Labels did not include the treatment details like dosage. Only cells with 44-46 chromosomes were analysed for structural aberrations. Cells with deviating numbers were observed separately. Classification of structural aberrations was based on the scheme described by ISCN.
Treatment of data:
After completion of the microscopic analysis, data were decoded and the aberrant cells in each culture were categorised as follows:
1. cells with structural aberrations including gaps;
2. cells with structural aberrations excluding gaps;
3. polyploid, endoreduplicated or hyperdiploid cells.
The totals for cat. 2 in the negative control were compared with the current laboratory negative control ranges for acceptability reasons.

Evaluation criteria:

A test article is considered as positive if:
1. the proportions of cells with structural aberrations at one or more concentration exceeds the normal range in both replicates, and
2. a statistical significant increase in the proportion of cells with structural aberrations (excl. gaps) occurs at these doses.

Statistics:

Statistical analysis by Fisher's exact test. The proportions of aberrant cells in each replicate were also used to establish acceptable heterogenecity between replicates by means of a binomial disperion test. Probability values of p ≤ 0.05 were to be accepted as significant.

Species / strain:

lymphocytes: human

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

(> 500 µg/ml)

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Species / strain:

lymphocytes: human

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

(> 500 µg/ml)

Remarks on result:

other: other: Experiment 1

Remarks:

Migrated from field 'Test system'.

Conclusions:

Interpretation of results (migrated information):
negative with metabolic activation
negative without metabolic activation

Ceraphyl RMT did not induce chromosome structural aberrations in cultured human peripheral blood lymphocytes when tested up to its solubility limit in culture medium in either the absence or presence of S-9.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Additional information

Additional information from genetic toxicity in vitro:

Justification for selection of genetic toxicity endpoint
Chromosome Aberrations in Cultured Human Peripheral Blood Lymphocytes.

Justification for classification or non-classification

The substance induce no significant response in an in-vitro gene mutation study in bacteria or in human cells.