Registration Dossier

Administrative data

Description of key information

The test article was not carcinogenic in rats

Key value for chemical safety assessment

Carcinogenicity: via oral route

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
NOAEL
58 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

An oncogenicity and chronic toxicity study was performed with groups of 70 male and 70 female rats of the CD strain. The animals received diet containing the test item at concentrations of 0 (control), 250, 750 or 2000 ppm for two years. At termination of the treatment period, all surviving animals were killed and submitted to necropsy and histological evaluation. Mortality anong females receiving 750 ppm was significantly higher (P < 0.05) than it was among control females. This difference arose during the terminal stages of the study and was considered fortuitous and unrelated to treatment. In comparison with control males, significantly fewer (P < 0.05) male rats receiving 2000 ppm bore subcutaneous masses. This was generally in agreement with the results of the microscopic examination conducted terminally. Food consumption of males receiving 2000 ppm was consistently slightly higher than that of the controls. Significantly increased bodyweight gain (P < 0.01) was recorded during the first year of treatment for females receiving 2000 ppm. During the first six months of treatment, slightly increased food utilisation efficiency was recorded for males receiving 2000 ppm and for all three treated female subgroups. Ophthalmoscopy, haematology, blood chemistry and urinalysis did not reveal any persistent differences between control and treated rats. Analysis of organ weights recorded for rats killed at termination of testing did not revealany significant inter-group differences. The macroscopic and microscopic examination of the tissues revealed, in all groups, a range of morphologic change and neoplasms which were of a type and frequency commonly found in the CD rat. It was concluded that test material administered at dietary concentrations as high as 2000 ppm for a two year period, i.e. throughout most of the life-span of the CD rat, was tolerated without adverse effect.

Justification for classification or non-classification

There are conclusive but not sufficient data for classification of the substance with regard to carcinogenicity.

Test substance is not classified for this endpoint in accordance to the CLP Regulation (EC) No 1272/2008