Propyl chloroformate

Endpoint summary

Description of key information

oral LD50: 1000 - 1470 mg/kg (rat)

inhalative LC50: 1.6 mg/L/1h (rat)

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Dose descriptor:

LD50

Additional information

Oral:

In an OECD TG 401 study, Sprague-Dawley rats (5/sex/dose) were administered 46.4, 100, 147, 681, 1000, 1470, 2150 or 3160 mg/kg bw propyl chloroformate by gavage (vehicle; olive oil). The acute oral LD₅₀was 1210 mg/kg bw (95% CL =1055.4 - 1391.3 mg/kg bw). Except for aggressiveness at 147 mg/kg, no clinical effects or mortality were seen at first three doses. Clinical signs of dyspnoea, apathy, and staggering were observed at higher concentrations. At 681 and 1000 mg/kg, 1/10 animals died. Mortality occurred in 9/10 animals at 1470 mg/kg. All animals died at higher doses. In animals that died, necropsy revealed necrotic white mucosa in the stomach and intestine (BASF AG, 1980).

 

Inhalation:

Study is comparable with the inhalation hazard test described in the Annex of OECD Guideline 403 (adopted 1981)with acceptable restrictions mostly due to reduced reporting in times before GLP. Rats were exposed for 3 min and 1 h, respectively, to a vapour saturated atmosphere. Concentration was stated in the raw data to be 1.385 mg/L in the case of the 3 min exposure and 1.019 mg/L in case of the 1 h exposure. A measured concentration of 40 ppm of phosgen above the test substance in the 3 min trial indicates a partial hydrolisation of the test substance. 12/12 animals died within 2 h after 3 min exposure to 1.385 mg/L; 3/10 animals died within 6d after 1h exposure to 1.019 mg/L.

Animals of the 3 min exposure showed vigorous attempts to escape, extremely severe irritation to the mucosa and gasping; animals of the 1 h exposure showed restlessness, irritation to the mucosa and dyspnea.

Necropsy findings were congestion and edema of the lungs in the 3 min treatment and acute pulmonary emphysema in the 1 h treatment, respectively (BASF 1970).

 

In an inhalation study comparable to OECD TG 403, rats (5/sex/dose) were exposed by whole-body inhalation for 1 hour to 0.97, 1.3, 3.9, 12 or 84 mg/L propyl chloroformate vapor (nominal concentration). No mortality or clinical signs were noted at 0.97 mg/L. At 1.3 mg/L, 2/10 animals died and bloody nasal discharge and dyspnea were observed. All animals exposed to higher concentrations died. Dose-dependent hyperemia of the lung was observed at necropsy of in all surviving and deceased animals (IBT, 1970). The LC₅₀was 1.6 mg/L/1h. According to CLP No. 1272/2008 Part 3.1.2, for the conversion from 1 h to 4 h exposure, the data are divided by factor 2

Dermal:

No adequate acute dermal toxicity data.

New Zealand White rabbits (2/sex/dose) were dermally treated with 6.8 or 10.2 g/kg bwpropyl chloroformate. There were no deaths at 6.8 g/kg bw. Two animals died at 10.2 g/kg bw. Severe irritation, edema, and burns were observed at the end of the 24-hour exposure period. Six days later, the skin was necrotic. Surviving animals did not gain weight. The dermal LD₅₀was approximately 10.2 g/kg bw (IBT, 1970).

 

Justification for classification or non-classification

Based on the results of the acute toxicity testing, the test item is classified as acute oral cat. 4 (H302) and acute inhalation cat. 2 (H330) according to Regulation (EC) No 1272/2008 (CLP).

Nevertheless, the substance is classification is according to the legally binding classification in Annex VI to EU Regulation 1272/2008 as acute inhalation cat 3 (H331).