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Administrative data

Description of key information

In a subchronic study 4 dogs/group were given daily oral doses of 5, 20, or 80 mg/kg of o-chlorotoluene (OCT). The control group was given 5% aqueous acacia solution, 0.5 ml/kg. Daily doses were administered for 3 month by capsule. A general observation, body weight changes, hematology, clinical biochemistry, and urinalysis were performed. Organ weights, bone marrrow and hepatic microsomal activity was examined  and pathological findings were evaluated.
In a further study monochlortoluene Isomeres were orally administrated 90-day to purebred beagle dogs at dose levels of either 0, 30, 100 or 300 m/kg/day (administered via capsule). The following parameters were examined: food consumption, behavioral reactions, mortality, blood chemistry, urinalysis, organ weights, gross pathology, microscopic pathology.

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Endpoint conclusion
Dose descriptor:
NOAEL
20 mg/kg bw/day

Additional information

In dogs (4 dogs/group), oral application of 2-chlorotoluene in doses of 0, 20, 80 and 320 mg/kg bw and day by capsule for 3 months resulted in a NOEL of 20 mg/kg bw and day (Gibson et al. 1974b, Hill 1981). In all dose groups there were no treatmentrelated effects on behaviour, survival, hematology, clinical chemistry, histopathology, eyes and bone marrow. Occasional episodes of vomiting in 1/4 females and red blood in the feces of this animal given 80 mg/kg bw is regarded to be the physiological response to the treatment with the slightly irritating compound.

Justification for classification or non-classification

Due to the result of the oral repeated dose key-study in dogs a classification is not justified