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Toxicological information

Genetic toxicity: in vitro

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Administrative data

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:
31 MAR 1989 to 01 OCT 1989
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: The study was performed following GLP and according to EU B.10 standardized method.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1989
Report Date:
1989

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
EU Method B.10 (Mutagenicity - In Vitro Mammalian Chromosome Aberration Test)
Deviations:
no
GLP compliance:
yes (incl. certificate)
Type of assay:
in vitro mammalian chromosome aberration test

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
Betaine monohydrate, >95% purity

Method

Species / strain
Species / strain / cell type:
lymphocytes: primary cells
Additional strain / cell type characteristics:
not applicable
Metabolic activation:
with and without
Metabolic activation system:
S-9
Vehicle / solvent:
Betaine was completely solved in culture medium: bicarbonate buffered RPMI 1640 medium containing 15% foetal bovine serum (both Gibco Europe Ltd.), 1% phytohaemagglutinin (PHA, Burroughs Wellcome) and 100 units/ml penicillin and streptomycin.
Controlsopen allclose all
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
True negative controls:
yes
Positive controls:
yes
Positive control substance:
cyclophosphamide
Remarks:
Migrated to IUCLID6: in the presence of S-9 metabolic activation
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
True negative controls:
yes
Positive controls:
yes
Positive control substance:
mitomycin C
Remarks:
Migrated to IUCLID6: in the absence of S-9 metabolic activation
Evaluation criteria:
Chromatid and chromosome gaps and breaks as well as fragments and re-arrangements were all recorded on raw data sheets with the stage coordinates (vernier readings) of every cell containing aberrations.
Statistics:
Chi squared -test

Results and discussion

Test results
Species / strain:
lymphocytes:
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
no 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

Rangefinder Mitotic Index (MI) and Relative Mitotic Index

Point

 

MI

Relative MI

Point

 

MI

Relative MI

Control

-S-9

855

100

Control

+S-9

13.45

100

1.6 µg/mL

-S-9

10.17

118.9

1.6 µg/mL

+S-9

11.11

82.6

8 µg/mL

-S-9

9.06

106.0

8 µg/mL

+S-9

8.45

62.8

40 µg/mL

-S-9

7.03

82.5

40 µg/mL

+S-9

7.24

53.8

200 µg/mL

-S-9

8.18

95.7

200 µg/mL

+S-9

7.14

53.1

1000 µg/mL

-S-9

10.51

112.9

1000 µg/mL

+S-9

4.90

36.4

2000 µg/mL

-S-9

9.96

116.5

2000 µg/mL

+S-9

5.97

44.4

4000 µg/mL

-S-9

11.13

130.5

4000 µg/mL

+S-9

3.95

29.4

7000 µg/mL

-S-9

13.17

154.0

7000 µg/mL

+S-9

5.74

42.7

10000 µg/mL

-S-9

14.07

164.6

10000 µg/mL

+S-9

5.16

38.4

 

Metaphase Analysis Without Activation (-S9)

Treatment

Replicate No.

No. cells scored

Gaps

Aberrations per 100 cells

Iso-locus Del.

Total Aberrations

% cells with aberrations

Others*

Mitotic index

Chromosome

Chromatid

Del.

Exchange

Del.

Exchange

+gaps

-gaps

+gaps

-gaps

Control

A

100

6

0

0

0

0

0

6

0

6

0

0

9.70

B

100

6

0

0

0

0

0

6

0

5

0

0

6.06

 

Mean/100 cells based on 200 cells scored

6

0

0

0

0

0

6

0

5.5

0

0

7.88

1000 µg/mL

A

100

1

0

0

0

0

0

1

0

1

0

0

13.56

B

100

1

0

0

2

0

0

3

2

3

2

0

9.93

 

Mean/100 cells based on 200 cells scored

1

0

0

1

0

0

2

1

2

1

0

11.75

3333 µg/mL

A

100

5

0

0

0

0

0

5

0

5

0

0

4.64

B

100

1

1

0

1

0

0

3

2

3

2

0

7.65

 

Mean/100 cells based on 200 cells scored

3

0.5

0

0.5

0

0

4

1

4

1

0

6.15

10000 µg/mL

A

100

4

0

0

0

0

0

4

0

4

0

0

7.66

B

100

2

0

0

0

0

0

2

0

2

0

0

3.77

 

Mean/100 cells based on 200 cells scored

3

0

0

0

0

0

3

0

3

0

0

5.72

*Cells which showed fragmentation were excluded from the calculation of aberrations per 100 cells but are included in cells with aberrations.

 

Metaphase Analysis With Activation (+S9)

Treatment

Replicate No.

No. cells scored

Gaps

Aberrations per 100 cells

Iso-locus Del.

Total Aberrations

% cells with aberrations

Others*

Mitotic index

Chromosome

Chromatid

Del.

Exchange

Del.

Exchange

+gaps

-gaps

+gaps

-gaps

Control

A

100

7

0

0

0

0

0

7

0

7

0

3

8.57

B

100

0

0

0

1

0

0

1

1

1

1

0

4.61

 

Mean/100 cells based on 200 cells scored

3.5

0

0

0.5

0

0

4

0.5

4

0.5

1.5

6.59

1000 µg/mL

A

100

11

0

0

4

0

0

15

4

14

4

0

5.22

B

100

6

0

0

2

0

0

8

2

8

2

0

7.88

 

Mean/100 cells based on 200 cells scored

8.5

0

0

3

0

0

11.5

3

11

3

0

6.55

3333 µg/mL

A

100

11

0

0

1

0

0

12

1

12

1

1

8.53

B

100

1

0

0

1

0

0

2

1

2

1

0

7.69

 

Mean/100 cells based on 200 cells scored

6

0

0

1

0

0

7

1

7

1

0.5

8.11

10000 µg/mL

A

100

12

0

0

0

0

0

12

0

11

0

1

5.78

B

100

4

0

0

1

0

0

5

1

5

1

1

3.54

 

Mean/100 cells based on 200 cells scored

8

0

0

0.5

0

0

8.5

0.5

8

0.5

1

4.66

*Cells which showed fragmentation were excluded from the calculation of aberrations per 100 cells but are included in cells with aberrations.

 

Positive Controls

Treatment

Replicate No.

No. cells scored

Gaps

Aberrations per 100 cells

Iso-locus Del.

Total Aberrations

% cells with aberrations

Others*

Chromosome

Chromatid

Del.

Exchange

Del.

Exchange

+gaps

-gaps

+gaps

-gaps

MMC (-S9)

A

25

12

0

4

20

12

8

56

44

40

36

0

B

25

12

4

0

12

4

8

40

28

44

36

8

 

Mean/100 cells based on 50 cells scored

12

2

2

16

8

8

48

36

42

36

4

CPA (+S9)

A

25

12

8

0

16

0

8

44

32

36

32

0

B

25

8

0

0

12

0

12

32

24

32

28

4

 

Mean/100 cells based on 50 cells scored

10

4

0

14

0

10

38

28

34

30

2

*Cells which showed fragmentation were excluded from the calculation of aberrations per 100 cells but are included in cells with aberrations.

 

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
negative expert judgement

Based on this study betaine does not have clastogenic properties, when tested in human lymphocytes at concentrations up to a limit of 10000 microgram per millilitre.
Executive summary:

An in vitro mammalian chromosome aberration test with primary human lymphocytes was performed with the test substance according to EU Method B.10. No genotoxicity or cytotoxicity was observed during the study. The test substance does not have clastogenic properties, when tested in human lymphocytes at concentrations up to a limit of 10000 µg/mL.