Registration Dossier

Administrative data

Description of key information

Acute Toxicity:
- oral: LD50: 540 kg/kg bw (rat)
- dermal: LD50: 582 mg/kg bw (rabbit)
- inhalation: LC50: 17.3 mg/L air (rat)

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion
Dose descriptor:
LD50
Value:
540 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion
Dose descriptor:
LC50
Value:
17 300 mg/m³

Acute toxicity: via dermal route

Endpoint conclusion
Dose descriptor:
LD50
Value:
582 mg/kg bw

Additional information

Oral:

In two studies with only limited data provided, the test substance caused dose and concentration dependent toxicity after a single ingestion (LD50: 540 mg/kg bw (20%), Smyth 1951, reliability: 2; LD50: > 710 mg/kg bw (10%), Union Carbide 1979, reliability: 2). Doses of 250, 500, 1000 and 2000 mg/kg bw of an 20% aqueous solution or 355, 710 and 1420 mg/kg bw of an 10% aqueous solution were applied by gavage followed by an observation period of 7 days. Main clinical signs observed were sluggishness, gasping and reduced body temperature. At necropsy, congestion of the lungs, liver and kidney, and haemorrhagic stomachs and intestines were observed. In the Carbide study, a LD50 < 178 mg/kg was obtained when test substance was administered undiluted (Union Carbide 1979, reliability: 2). However, the fact that indiluted test substance (a corrosive substance) was ingested and its subsequent corrosive (as indicated by distended, liquid filled, red and walls thickened stomachs, which were ulcerated and adhered to surrounding tissue) may have secondary lead to death of treated animals.

Inhalation:

In a 4 h inhalation study a metered concentration of 8000 ppm resulted in death within few hours and the LC50 was set to be 5700 ppm (17.3 mg/l air, Union Carbide 1979, reliability: 2). Irritation of the extremities, respiratory distress and loss of coordination were observed during exposure to this concentration and to 4000 ppm. Gross necropsy revealed red lungs and yellowed, gas- and liquid-filled intestines. Additional data were available from an inhalation risk test (IRT) which meets generally accepted scientific principles (BASF AG, 1955; reliability score 2). The inhalation of a saturated vapor-air mixture for 1 min caused mortality. Clinical signs were convulsions, lateral position, twitching, dyspnoea. At necropsy, pulmonary hyperemia was observed. In a second IRT mortality occurred after 3.75 min of exposure (Union Carbide 1950; reliability score: 2).

Dermal:

Acute dermal toxicity was evaluated similar to Draize. Undiluted doses of 179, 355, 710 and 1420 mg/kg bw were applied for 24 h to the clipped trunk of male albino rats and the corresponding LD50 was found to be 582 mg/kg bw (Smyth 1951, reliability: 2). A similar study with doses of 377, 710 and 1420 mg/kg bw showed comparable results (LD50: 628 mg/kg bw, Myers 1997, reliability: 2). In both studies the substance caused local effects like hemorrhage and necrosis of the skin and underlaying muscular layers. Loss of coordination was also observed. At gross necropsy examination mottled surfaces of the livers and kidneys, and congested or hemorrhagic intestines were noted. Spleens were darkened to the point of being called black, pancreas congested and testes hemorrhagic.

Justification for classification or non-classification

EU classification according to Annex I of Directive 67/548/EEC: Xn, R20/21/22;

According to the EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008 subtance is classified as Cat. 4 harmful if swallowed, Cat. 4 harmful if inhaled and Cat. 3 toxic in contac with skin.