2.1.2 Acute Toxicity

The available human and animal data indicate that breathing of ethylbenzene vapours at high concentrations over prolonged periods can cause central nervous system (CNS) depression resulting in dizziness, headache, drowsiness, nausea and loss of coordination. Inhalation studies in rats indicate that ethylbenzene has a moderate toxicity (lethal concentration LC₅₀ (4 h) = 2-20 mg/l = 460 – 4600 ppm).

It can be concluded from animal experiments that the acute oral toxicity of ethylbenzene is low. The oral lethal dose LD₅₀ (rat) is reported to be well above 2000 mg/kg body weight. As the oral toxicity is low, any small amounts of ethylbenzene accidentally ingested are unlikely to cause injury. Ingestion of large amounts of ethylbenzene may cause slight to moderate irritation of the mouth, throat and gastro-intestinal tract. After swallowing large amounts, aspiration into the lungs may cause chemical pneumonitis, which can be fatal.

The dermal toxicity of ethylbenzene is low; the LD50 in rabbits is above 5000 mg/kg body weight.

Note that in addition to CNS depression, in cases of high exposure in incidents and abuse, solvents may increase the sensitivity of the heart to endogenous catecholamines leading to potentially fatal cardiac conditions.

CEFIC
Avenue E Van Nieuwenhuyse 4
B- 1160 Brussels

Patrick Detournay
T +32 2 676 72 05
E pdt@cefic.be