Registration Dossier

Administrative data

Description of key information

No experimental repeated-dose data is available on pitch itself. A structure-related coal-tar material produced no particular, treatment-related toxicity in male and female mice receiving the test material in the feed for up to 6 months. The NOAEL, 0.5 % in the diet, is estimated to correspond to approximately 400 mg/kg bw/d. Early not verifiable reports indicate that young pigs may have a significant lower tolerance to ingested coal-tar pitch or coal tar than the adult animals.    

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Endpoint conclusion
Endpoint conclusion:
adverse effect observed
Dose descriptor:
NOAEL
400 mg/kg bw/day
Study duration:
subchronic
Species:
rat

Additional information

Apart from one oral study of limited significance in pigs, no repeated-dose toxicity studies with pitch addressing effects other than carcinogenicity have been located. The subchronic feeding study in mice with coal-tar material (compared to pitch a worst case) indicates that more marked toxicity following long-term exposure to pitch is unlikely to occur.

Tars and pitches constitute a family of products that result from different distillation steps of coal (condensation products and distillation residues). Depending on distillation step and distillation temperature, constituents of the products and their portions are variable. But major components of all the distillation products and residues are condensed ring aromatic hydrocarbons in varying composition (i.e. polynuclear aromatic hydrocarbons). Major toxicological effects of these products will primarily be caused by the PAH fraction in the respective substances. Especially for toxicological endpoints that fall into the toxicological action profile of PAH, it is justified to use related tars and pitches as supporting substances to characterise potential effects of pitch, coal tar, high temp.


Repeated dose toxicity: via oral route - systemic effects (target organ) digestive: liver

Justification for classification or non-classification

Pitch is not classifiable, as there was no evidence for specific target-organ effects at doses lower than 100 mg/kg bw/d (test material: coal tar).