Nickel bis(sulphamidate)

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro DNA damage and/or repair study

Remarks:

Type of genotoxicity: other: sister chromatid exchange

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Meets generally accepted scientific standards with acceptable restrictions. No positive control group included. Purity of test substance not reported.

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

publication

Title:

Interaction of nickel with mutagens in the induction of sister chromatid exchanges in human lymphocytes.

Author:

Katsifis, S.P., P.L. Kinney, S. Hosselet, F.J. Burns, and N.T. Christie.

Year:

1996

Bibliographic source:

Mutation Research. 359:7-15.

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

A standard Test Guideline was not specified in this study.

GLP compliance:

not specified

Type of assay:

sister chromatid exchange assay in mammalian cells

Test material

Test material information

Constituent 1

Reference substance name:

Nickel sulphate

EC Number:

232-104-9

EC Name:

Nickel sulphate

Cas Number:

7786-81-4

Molecular formula:

NiSO4

IUPAC Name:

nickel(2+) sulfate

Method

Species / strain

Species / strain / cell type:

lymphocytes:

Test concentrations with justification for top dose:

Nickel sulfate: 0, 0.5, 1.0, 2.5, 5.0, 7.5, 10.0, or 25.0 uM UV-light: 200 and 1000 ergs/mm2 X-rays: 0.10, 0.25, and 0.40 Gy Cr(VI), added as CaCrO4: 0.65 and 1.30 uM.

Details on test system and experimental conditions:

Cultures of human lymphocytes were obtained from 25-40 year old non-smoking human subjects. Blood (0.8 ml) was added to RPMI 1640 medium to which 10% bovine serum, 100 U/ml penicillin and 100 ug/ml streptomycin had been added. Prior to incubation, 20 ug/ml phytohemmagglutin, the various nickel sulfate concentrations (or Cr(VI) concentrations), and 20 ug/ml 5-bromo-2-deoxyuridine (BrdU) were added to each culture flask (final volume = 10 ml). Cells were incubated in the absence of light for 68.5 hours at 37 deg. C. A spindle inhibitor (colcemide, 0.08 ug/ml) was added at 2.5 h prior to harvesting. After 68.5 hours incubation, cells were harvested. Flasks were centrifuged and the supernatant was discarded. Cells were then treated with 75 mM KCl solution, centrifuged again, and the supernatant was discarded. Cells were fixed (methanol/acetic acid) and slides were prepared, stained with Giemsa, and blind scored. Second mitotic division (20-30 well-spread metaphases per culture) with distinct staining of SCEs was scored for each treatment. Each point of breakage and rejoining was counted as one SCE. Centromeric exchanges were scored "if an obvious twisting at this point was excluded." For the test with X-irradiation, 2 ml of whole blood were placed in 15-ml centrifuge tubes and irradiated with 1.8 meV X-rays before establishing cell cultures. For the test with UV-light, 0.80 ml of whole blood were added to 40 mm diameter Petri dishes and irradiated with UV light at a wavelength of ~254 nm. The dose rate at the irradiated surface was 20 ergs/mm2/sec.

Statistics:

SCE responses for individual treatments were evaluated using one-way ANOVA and/or Dunnett's test. For the interaction of Ni(II), X-ray, UV-light, and Cr(VI), an interaction factor was calculated based on the formula of Schlesinger et al. (1992).

Results and discussion

Test results

Species / strain:

lymphocytes:

Metabolic activation:

not specified

Genotoxicity:

positive

Cytotoxicity / choice of top concentrations:

not specified

Additional information on results:

Results of separate experiments with NiSO4 (alone):
 
Experiment 1 (Frequency of SCE/cell (standard error), by concentration of NiSO4 tested):
0 uM (control): 4.72 (0.25) 
5 uM: 6.24 (0.32)*
10 uM: 6.37 (0.34)*
25 uM: 6.99 (0.33)*
* significantly different from control, p<0.05
 
Experiment 2 (Frequency of SCE/cell (standard error), by concentration of NiSO4 tested):
0 uM (control): 5.73 (0.31)
0.5 uM: 6.60 (0.33)
1.0 uM: 6.86 (0.34)
2.5 uM: 6.79 (0.32)
5.0 uM: 6.44 (0.25)
7.5 uM: 6.51 (0.31)
 
Experiment 3 (Frequency of SCE/cell (standard error), by concentration of NiSO4 tested):
0 uM (control): 5.87 (0.36)
0.5 uM: 7.29 (0.42)*
1.0 uM: 9.07 (0.40)*
2.5 uM: 9.91 (0.49)*
5.0 uM: 9.12 (0.40)*
7.5 uM: 8.91 (0.54)* * significantly different from control, p<0.05
 
The frequencies of SCEs induced in human lymphocytes treated with X-irradiation, UV-light, and Cr(VI) were dose-dependent. 
Combined treatments of Ni(II) + UV-light, X-irradiation, or Cr(VI) interacted in an antagonistic fashion.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Applicant's summary and conclusion

Executive summary:

STUDY RATED BY AN INDEPENDENT REVIEWER.

ROBUST SUMMARY DEVELOPED BY AN INDEPENDENT REVIEWER.

Robust Summary for Katsifis et al.(1996):

PURPOSE: Demonstrate that Ni(II), Cr(VI), UV-light, and X-rays (alone and in combination) are capable of inducing sister chromatid exchanges (SCEs) in human lymphocytes and that SCEs are formed from the antagonistic interaction of Ni with X-rays, UV-light, or Cr(VI).

TREATMENT GROUPS: Nickel sulfate: 0, 0.5, 1.0, 2.5, 5.0, 7.5, 10.0, or 25.0 uM UV-light: 200 and 1000 ergs/mm2 X-rays: 0.10, 0.25, and 0.40 Gy Cr(VI), added as CaCrO4: 0.65 and 1.30 uM.

METHOD DESCRIPTION: Cultures of human lymphocytes were obtained from 25-40 year old non-smoking human subjects. Blood (0.8 ml) was added to RPMI 1640 medium to which 10% bovine serum, 100 U/ml penicillin and 100 ug/ml streptomycin had been added. Prior to incubation, 20 ug/ml phytohemmagglutin, the various nickel sulfate concentrations (or Cr(VI) concentrations), and 20 ug/ml 5-bromo-2-deoxyuridine (BrdU) were added to each culture flask (final volume = 10 ml). Cells were incubated in the absence of light for 68.5 hours at 37 deg. C. A spindle inhibitor (colcemide, 0.08 ug/ml) was added at 2.5 h prior to harvesting. After 68.5 hours incubation, cells were harvested. Flasks were centrifuged and the supernatant was discarded. Cells were then treated with 75 mM KCl solution, centrifuged again, and the supernatant was discarded. Cells were fixed (methanol/acetic acid) and slides were prepared, stained with Giemsa, and blind scored. Second mitotic division (20-30 well-spread metaphases per culture) with distinct staining of SCEs was scored for each treatment. Each point of breakage and rejoining was counted as one SCE. Centromeric exchanges were scored "if an obvious twisting at this point was excluded." For the test with X-irradiation, 2 ml of whole blood were placed in 15-ml centrifuge tubes and irradiated with 1.8 meV X-rays before establishing cell cultures. For the test with UV-light, 0.80 ml of whole blood were added to 40 mm diameter Petri dishes and irradiated with UV light at a wavelength of ~254 nm. The dose rate at the irradiated surface was 20 ergs/mm2/sec.

STATISTICAL METHODS: SCE responses for individual treatments were evaluated using one-way ANOVA and/or Dunnett's test. For the interaction of Ni(II), X-ray, UV-light, and Cr(VI), an interaction factor was calculated based on the formula of Schlesinger et al. (1992). Results of separate experiments with NiSO4 (alone): Experiment 1 (Frequency of SCE/cell (standard error), by concentration of NiSO4 tested): 0 uM (control): 4.72 (0.25) 5 uM: 6.24 (0.32)* 10 uM: 6.37 (0.34)* 25 uM: 6.99 (0.33)* * significantly different from control, p0.05 Experiment 2 (Frequency of SCE/cell (standard error), by concentration of NiSO4 tested): 0 uM (control): 5.73 (0.31) 0.5 uM: 6.60 (0.33) 1.0 uM: 6.86 (0.34) 2.5 uM: 6.79 (0.32) 5.0 uM: 6.44 (0.25) 7.5 uM: 6.51 (0.31) Experiment 3 (Frequency of SCE/cell (standard error), by concentration of NiSO4 tested): 0 uM (control): 5.87 (0.36) 0.5 uM: 7.29 (0.42)* 1.0 uM: 9.07 (0.40)* 2.5 uM: 9.91 (0.49)* 5.0 uM: 9.12 (0.40)* 7.5 uM: 8.91 (0.54)* * significantly different from control, p0.05 The frequencies of SCEs induced in human lymphocytes treated with X-irradiation, UV-light, and Cr(VI) were dose-dependent. Combined treatments of Ni(II) + UV-light, X-irradiation, or Cr(VI) interacted in an antagonistic fashion.