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Toxicological information

Carcinogenicity

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Description of key information

Key value for chemical safety assessment

Carcinogenicity: via oral route

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
NOAEL
7.9 mg/kg bw/day
Study duration:
chronic
Species:
rat

Carcinogenicity: via inhalation route

Endpoint conclusion
Endpoint conclusion:
no study available

Carcinogenicity: via dermal route

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

Carworth Farms rats (10/sex/group) were fed diets fumigated with HCN for 2 years.The dietary concentrations were 100 and 300 mg/kg. The animals did not accept higher concentrations due to reduced palatability. Survival, body-weight gain, food intake, and clinical behaviour were not different between treated and control groups in the two year study. Absolute and relative organ weights were also comparable to controls. No treatment-related histopathological changes were observed in the organs examined. The NOAEL in this study was approximately 8.2 mg HCN/kg bw/d, or 7.9 mg CN ion/kg bw/d.


Justification for selection of carcinogenicity via oral route endpoint:
valid scientific study

Justification for classification or non-classification

HCN was used as a fumigant in food consumed by rats for a two year experimental period. No evidence of carcinogenicity was observed in any of the organs examined in the exposed animals. Hydrogen cyanide is not carcinogenic under conditions of this study.