Registration Dossier

Administrative data

Description of key information

In carcinogenicity studies and subchronic studies, histopathologic changes were noted at the site of entry following oral or inhalation administration, thus histopathologic changes were observed in the stomach following oral administration and nasal turbinates following inhalation exposure to vapors. In addition, some slight histologic changes were observed in the liver and kidneys following both oral and inhalation exposure for 90 days; these occured at the same or higher doses than the portal of entry effects.

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Endpoint conclusion
Dose descriptor:
LOAEL
3 mg/kg bw/day

Repeated dose toxicity: inhalation - systemic effects

Endpoint conclusion
Dose descriptor:
LOAEC
95 mg/m³

Additional information

The lowest observable adverse effect level (LOAEL) for oral exposure of Sprague-Dawley rats to epichlorohydrin was 3 mg/kg/day for 10 days and 1 mg/kg/day was the no observed adverse effect level (NOAEL) for a 90 day oral exposure. These conclusions were the same whether the lesions were analyzed for each sex individually or whether the data in each study was pooled.

The NOAEC was 19 mg/m3 in the 90 day inhalation study in mice and two strains of rats. At higher concentrations, histopathologic changes were noted in the nasal epithelium and, to a lesser degree, in livers and kidneys.

In both the oral and inhalation studies, effects were mainly observed at the portal of entry; this constitutes a local effect. Slight histologic changes to the liver and kidneys constitute systemic effects.


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

Repeated dose toxicity: inhalation - systemic effects (target organ) respiratory: nose

Justification for classification or non-classification

Because effects noted in studies constituted portal of entry effects, and irritancy is already documented in acute classification, no additional classification is proposed.