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Administrative data

Description of key information

In an acute oral toxicity study (similar to OECD guideline 401) performed in mice, the LD50 was between 1960 and 4900 mg/kg bw.
In an acute dermal toxicity study (similar to OECD guideline 402) performed in rabbits, the LD50 was higher than 2000 mg/kg bw.

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
LD50
2 000 mg/kg bw
Quality of whole database:
Study performed similarly to OECD guideline 401 with deviations but considered as appropriate and reliable to complete this endpoint.

Acute toxicity: via inhalation route

Endpoint conclusion
Endpoint conclusion:
no study available

Acute toxicity: via dermal route

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
LD50
2 000 mg/kg bw
Quality of whole database:
Study performed similarly to OECD guideline 402 with deviations but considered as appropriate and reliable to complete this endpoint.

Additional information

In an acute oral toxicity study (similar to OECD Guideline 401), 3 groups of 1, 3 and 1 mice/sex were given a single oral dose of nopyl acetate at 2, 5 and 10 mL/kg bw, respectively. Animals were then observed for mortality, clinical signs and bodyweights for 7 days and were all macroscopically necropsied after sacrifice. Mortalities at 2, 5 and 10 mL/kg bw were 0, 100 and 100 %, respectively. Signs of toxicity described included: hypothermia, stress, somnolence. All mice dosed at 5 and 10 mL/kg bw were cyanosed and died 18 h after the treatment.

The acute oral LD50 of nopyl acetate was considered to be between 2 and 5 mL/kg bw (equivalent to 1960-4900 mg/kg bw) in mice.

In an acute dermal toxicity study (limit test), a group of 10 New Zealand White rabbits were administered a single dermal dose of nopyl acetate at 2000 mg/kg bw on clipped abraded abdominal skin using an occlusive patch for 24 h. Animals were then observed for mortality, clinical signs, bodyweights and dermal reactions for 7 days and were all macroscopically necropsied after sacrifice. No deaths occurred throughout the study. Normal body weight gain was observed in all animals. At necropsy, macroscopic examination of main organs showed no abnormalities. Adverse dermal reactions noted were slight to moderate erythema and edema, which completely recovered to normal within four days.

The acute dermal LD50 of nopyl acetate was therefore higher than 2000 mg/kg bw under the test conditions.

Acute oral and dermal toxicity studies indicated limited toxicological effects at 2000 mg/kg bw.


Justification for selection of acute toxicity – oral endpoint
Only one study available for this endpoint

Justification for selection of acute toxicity – inhalation endpoint
Acute toxicity is already assessed by two different routes of exposure (oral and dermal routes), that showed very low toxicity, with high LD50 values.
Moreover, the vapour pressure of Nopyl acetate (1.33 Pa at 20°C) indicates low volatility. Therefore, no exposure by inhalation is expected and in accordance with column 2 of REACH Annex VIII (§8.5), the acute toxicity by inhalation does not need to be conducted.

Justification for selection of acute toxicity – dermal endpoint
Only one study available for this endpoint

Justification for classification or non-classification

Oral and dermal LD50 are higher than 2000 mg/kg bw in mice and rabbits, respectively, therefore nopyl acetate is not classified for acute toxicity according to Directive 67/548/EEC and CLP Regulation (EC) No 1272/2008.