Trinickel disulphide

Acute Toxicity: other routes

Administrative data

Endpoint:

acute toxicity: other routes

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Meets generally accepted scientific standards, well documented and acceptable for publication.

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

publication

Title:

Relative susceptibilities of C57BL/6, (C57BL/6 x C3H/He)F1, and C3H/He mice to acute toxicity and carcinogenicity of nickel subsulfide

Author:

Rodriguez RE, Misra M, Diwan BA, Riggs CW, and Kasprzak KS

Year:

1996

Bibliographic source:

Toxicology. 107: 131-140

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Intramuscular injection of 0.5, 1.0, 2.5, 5.0, and 10 mg of Ni3S2/site into the thigh musculature of each of the two hind legs of 3 mouse strains, and observed for up to 78 weeks. The susceptibility of three strains of mice [C57BL/6 (C57BL), (C57BL/6 X C3H/He)F1 (B6C3Fl), and C3H/He (C3H)] to the toxicity and carcinogenicity of nickel subsulfide (Ni3S2) was assessed.

GLP compliance:

not specified

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Trinickel disulphide

EC Number:

234-829-6

EC Name:

Trinickel disulphide

Cas Number:

12035-72-2

Molecular formula:

Ni3S2

IUPAC Name:

(trinickel-1-ylidene)-1λ⁴-disulfene

Details on test material:

- Name of test material (as cited in study report): nickel subsulfide (Ni3S2)
- Physical state: particulate
- Other: <= 30 um; originated from INCO, Ltd. (Toronto, Canada)

Test animals

Species:

mouse

Strain:

other: C57BL/6, (C57BL/6 x C3H/He)F1, and C3H/He

Sex:

male

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: NCE-FCRDC, Animal Production Area (Frederick, MD)
- Age at study initiation: 6-8 weeks
- Weight at study initiation: 23-29 g
- Housing: polycarbonate cages on a hardwood chip bedding
- Diet (e.g. ad libitum): ad libitum NIH-31 open formula 6% Modified (Zeigler Brothers, Gardners, PA)
- Water (e.g. ad libitum): ad libitum

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 +/- 2
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

intramuscular

Vehicle:

other: 50% glycerol/water

Details on exposure:

Animals received injections of single doses of Ni3S2 suspension in 0.05 ml of 50% glycerol/water into the thigh musculature of both hind legs.

Doses:

0, 0,5, 1.0, 2.5, 5.0, and 10.0 mg Ni3S2/ injection site.

No. of animals per sex per dose:

30 mice per group per strain

Control animals:

yes

Details on study design:

- Duration of observation period following administration: up to 78 months
- Frequency of observations and weighing: every 2 weeks
- Necropsy of survivors performed: yes
- Other examinations performed: body weight, histopathology

Statistics:

The different effects of Ni3S2 doses on body weight gains among the three mouse strains were analyzed using a one-way analysis of variance, ANOVA. When statistically significant differences were indicated, Duncan's multiple range test was used to determine how the treatments differed from each other.

Results and discussion

Effect levels

Effect levels 1

Sex:

male

Dose descriptor:

LD50

Effect level:

5 other: mg/injection in C57BL mice

Remarks on result:

other: after 1 week

Effect levels 2

Sex:

male

Dose descriptor:

LD50

Effect level:

> 5 - < 10 other: mg/injection site in C3H mice

Remarks on result:

other: after 1 week

Effect levels 3

Sex:

male

Dose descriptor:

LD50

Effect level:

> 5 - < 10 other: mg/injection site in B6C3F1 mice

Remarks on result:

other: after 1 week

Mortality:

10 mg Ni3S2 dose: C3H mice > 50%, B6C3F1 > 80%, and C57BL > 90% lethality 1 week after exposure.
5 mg Ni3S2 dose: C3H mice < 5%, B6C3F1 > 30%, and C57BL > 50% lethality 1 week after exposure.
2.5 mg Ni3S2 dose: C3H mice 0%, B6C3F1 0%, and C57BL > 25% lethality 1 week after exposure.
1 mg Ni3S2 dose: C3H mice 0%, B6C3F1 0%, and C57BL < 5% lethality 1 week after exposure.
0.5 mg Ni3S2 dose: C3H mice 0%, B6C3F1 0%, and C57BL < 5% lethality 1 week after exposure.

Clinical signs:

Not applicable

Body weight:

The C3H and B6C3Fl mice given 5- and 10-mg Ni3S2 doses tended to gain less weight (P < 0.05 by Duncan's test) than mice given lower doses, or the control mice. This trend apparently reflected the chronic systemic toxicity of Ni3S2 and the morbidity due to tumors after 25 weeks of experiment. No such trend could be confirmed for C57BL mice, for whom statistical analysis was hampered by high mortality.

Gross pathology:

Examination of mice dying 1 to 7 days after i.m. Ni3S2 injection revealed morphologic changes only in the kidney and the injected muscles. In kidney, the microscopic lesions included necrosis and inflammation that were particularly severe in the C57BL strain. Nephritis and renal cortex regenerative hyperplasia were found frequently in mice of all three strains which received higher Ni3S2 doses (~2.5 mg) and died 6 and 7 days after the injection, with no apparent difference among the strains.

Other findings:

- Histopathology: Histological examination of the injected muscles of the control mice of all three strains from 1 to 14 days post-injection revealed inflammation with moderate hyperplasia, subsiding gradually with time. In the Ni3S2-treated mice, moderate necrotic, inflammatory, and moderate to severe hyperplastic changes were observed over the 14 day period around the injected Ni3S2 particles without any apparent strain-dependent difference in the severity or persistence of those changes.

Any other information on results incl. tables

The present study demonstrates strain-dependent susceptibility of mice to the acute Ni3S2 toxicity: C57BL > B6C3FI > C3H.

Applicant's summary and conclusion

Conclusions:

Strain-dependent susceptibility was observed in mice intramuscularly injected with high doses of Ni3S2, where the rank order of susceptibilty was C57BL > B6C3FI > C3H, for mortality 1 week after exposure. The C3H and B6C3F1 mice administered 5 and 10 mg Ni3S2 gained less weight than the lower dose or control groups. High dose exposure also induced renal necrosis and inflammation in C57BL mice, and nephritis and renal cortex hyperplasia in all mice that died 6 and 7 days after exposure. The authors suggest that the acute toxicity of nickel in mice is partly associated with higher antioxidant capacity of target organs (based on the results of a side study in which the muscular GSH levels and LPO levels were studied in mice exposed to Ni(II) acetate). However, the GSH and LPO levels in the most susceptible mouse strains (C57BL and B6C3F1) were not affected by Ni(II) acetate exposure, and the strain least susceptible to acute toxicity (C3H) showed only a transient and modest elevation in antioxidant response after exposure. This hypothesis, therefore, seems at odds with the data presented.

Executive summary:

Rodriguez et al. (1996) studied the susceptibility of three strains of mice [C57BL/6 (C57BL), (C57BL/6 X C3H/He)F1 (B6C3Fl), and C3H/He (C3H)] to the toxicity and carcinogenicity of nickel subsulfide (Ni3S2). Groups of 30 male mice of each strain were injected with single doses of 0.5, 1.0, 2.5, 5.0, and 10 mg of Ni3S2 /site into the thigh musculature of each of the two hind legs and observed for up to 78 weeks. Strain-dependent susceptibility was observed in mice intramuscularly injected with high doses of Ni3S2 , where the rank order of susceptibility based on mortality 1 week after exposure was C57BL > B6C3FI > C3H. The highest Ni3S2 dose was lethal within 1 week, with mortality rates of C57BL (93%), B6C3Fl (80%), and C3H (53%). The C57BL and B6C3F1 mouse strains also showed significant mortality 1 week after exposure to the next highest Ni3S2 dose (>50% and >30%, respectively). Even at 2.5 mg Ni3S2 , C57BL mice still demonstrated considerable morality (>25%).

The most susceptible C57BL mice also had the most severe necrotic/inflammatory kidney damage, compared with that in the other mice, while all the mice that died 6 and 7 days after exposure demonstrated nephritis and renal cortex hyperplasia regardless of strain. Ni3S2 deposited in the muscle appears to be a source of soluble nickel that can reach and damage the kidneys, although it is unclear why other organs failed to demonstrate similar damage. The C3H and B6C3F1 mice administered 5 and 10 mg Ni3S2 gained less weight than the lower dose or control groups, while the high mortality rates among C57BL mice prevented the authors from drawing any conclusions about high dose Ni3S2 exposure affecting the weight of these mice. The authors suggested that the acute toxicity of nickel in mice was partly associated with higher antioxidant capacity of target organs. This assertion was based on data collected in the current investigation, which indicated that the muscular GSH levels and lipid peroxidation (LPO) levels were studied in mice exposed to Ni(II) acetate). However, the GSH and LPO levels in the most susceptible mouse strains (C57BL and B6C3F1) were not affected by Ni(II) acetate exposure, and the strain least susceptible to acute toxicity (C3H) showed only a transient and modest elevation in antioxidant response (GSH levels) after exposure. The authors suggested that organs with greater antioxidant capacity are more prone to nickel toxicity; however, this seems at odds with the data presented. Collectively, these data indicated that intramuscular injection of Ni3S2 induced both local and distal tissue pathologies, including tumorigenesis, depending on the mouse strain under observation. It was not clear if such strain susceptibilities were associated with each of the strain’s muscle antioxidant capacity. STUDY RATED BY AN INDEPENDENT REVIEWER