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Administrative data

Description of key information

Subchronic exposure of rats to n-butyl acetate vapour resulted in acute, transient signs of reduced activity levels during exposure to 1500 and 3000 ppm. Decreased body weight and feed consumption were noted for the 1500 and 3000 ppm groups, but there was no systemic or organ-specific toxicity. Signs of upper respiratory tract irritation were seen in the nasal passages of 1500 and 3000 ppm animals, but there was no evidence of pulmonary toxicity. The no-observed-adverse-effect concentration (NOAEC) for this study is considered to be 500 ppm (2.4 mg/L).

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Endpoint conclusion
Endpoint conclusion:
no study available

Repeated dose toxicity: inhalation - systemic effects

Endpoint conclusion
Endpoint conclusion:
adverse effect observed
Dose descriptor:
NOAEC
2 400 mg/m³
Study duration:
subchronic
Species:
rat
Quality of whole database:
A reliable modern guideline-compliant 90-day study is supported by a reliable dose-ranging study; studies were performed using the read-across substance n-butyl acetate.

Repeated dose toxicity: inhalation - local effects

Endpoint conclusion
Endpoint conclusion:
adverse effect observed
Dose descriptor:
NOAEC
2 400 mg/m³
Study duration:
subchronic
Species:
rat
Quality of whole database:
A reliable modern guideline-compliant 90-day study is supported by a reliable dose-ranging study; studies were performed using the read-across substance n-butyl acetate.

Repeated dose toxicity: dermal - systemic effects

Endpoint conclusion
Endpoint conclusion:
no study available

Repeated dose toxicity: dermal - local effects

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

Male and female Sprague-Dawley rats (15 animals/sex/dose group) were exposed to nominal concentrations of 0, 500, 1500 or 3000 ppm of n-butyl acetate for 6 hours per day, 5 days per week for 13 consecutive weeks. The time-weighted average analytical concentrations were within 10% of the target concentrations. Transient signs of sedation were observed during exposure to the 1500 and 3000 ppm concentrations. Body weights were significantly reduced in the mid and high concentration groups. Feed consumption was significantly lower in the 1500 and 3000 ppm group in comparison to the control group. Organ weights affected: weights of liver, kidneys and spleen were significantly lower for the males of the highest concentration goup. Testes and adrenal gland weights for the mid and high concentration groups and the lung weights for the 3000 ppm males were significantly higher than for the control group. Additionally, effects on the stomach (probably stress related) and pulmonary system were observed: Females of the highest concentration group showed signs of irritation of the glandular stomach and necrosis in the non-glandular stomach. Some rats of the 1500 and 3000 ppm group showed degeneration of the olfactory epithelium along the dorsal medial meatus and ethmoturbinates of the nasal passages. The severity was mild to moderate for the 3000 ppm group and minimal to mild for the 1500 ppm group. There was no systemic, organ specific toxicity. The no-observed-adverse-effect concentration (NOAEC) for this study is 500 ppm (2.4 mg/L)



Justification for selection of repeated dose toxicity inhalation - systemic effects endpoint:
Study of longest duration in the preferred species

Repeated dose toxicity: inhalation - systemic effects (target organ) digestive: stomach

Justification for classification or non-classification

No effects observed in the subchronic exposure study to justify classification of hexyl acetate for repeated dose toxicity (STOT-RE) according to the CLP Regulation.