N-ethylpropylamine

Endpoint summary

Description of key information

No studies available investigating toxicokinetic, metabolism and distribution. An assessment of the toxicokinetic behaviour was made taken together the physico-chemical parameters of N-ethylpropylamine and all available substance-related toxicological informations.

Additional information

There was no data available for the determination of toxicokinetics, metabolism and distribution.

Assessment of Toxicokinetic Behaviour

N-ethylpropylamine (CAS-No. 20193-20-8) is a colourless liquid with a molecular weight of 87.16 g/mol and a vapor pressure of 86 hPa (20°C). It is very soluble in water (> 10000 mg/L) at 25°C and a pH value of 7.5, the log Pow is -0.4. Therefore, a wide distribution but no accumulation of the test substance is assumed.

 

Data for absorption can only be taken from acute (oral, inhalative and dermal) studies.

 

In an acute oral toxicity study (BASF AG 1977) a LD50 of 496 mg/kg bw for male and female rats was determined. Main clinical signs observed were apathy, ataxia and reduced pain reactions, catalepsia, tonic-clonic convulsions. Three days post application animals were considered as normal. At necropsy, partially blood filled and reddened stomachs and bowels were observed at the dead animals which were due to the corrosive potential of the test substance. The sacrificed animals didn't show abnormalities. Therefore bioavailability of N-ethylpropylamine after oral administration is indicated. The inhalation of saturated vapor-air mixtures caused mortality during and after exposure. All male and female rats died. Symptoms described in the first inhalation hazard test (BASF AG 1979) included signs of irritation of the mucous membranes, dyspnoea, cyanosis, opacity. Post mortems showed dilatation of the right heart ventricle, general congestion and pulmonary emphysema. The animals in the second inhalation hazard test showed defending moves, turns in the glass cylinders, gasping, lacrimation and bloody snouts (BASF AG 1977). The gross pathological observation showed indurated, deep red noses (BASF AG 1977). It is also possible that vapors of very hydrophilic substances may be retained within the mucus (ECHA guidance document 7c, 2008), but due to the test results and the vapor pressure of 86 hPa (20°C) bioavailability of N-ethylpropylamine after inhalative administration is indicated. However, the main effects are local effects due to the corrosive potential of the test substance.

In an acute dermal toxicity study (BASF AG 1978) the LD50 for male and female rabbits was > 200 mg/kg bw. No mortality and systemic toxicity was observed at this dose. 5 days post application the exposed area is leathery, coarse, dry and heavy scabbed with a dark red to black colour which is also a consequence of the corrosive potential of the test substance. Additionally, the Log P value lies between 1 and 4 with a high water solubility which lead to the assumption that the substance could be absorbed via the dermal route (ECHA GD 7c, 20012). Nevertheless, the primary effect was the local effect which might therefore lead to destruction of membrane barriers.

 

Taken together, N-ethylpropylamine resulted in mortality after inhalation and oral exposure. Thus, the substance might be systemically available via the inhalation and oral route of exposure. The dermal exposure didn't lead to mortality or systemic toxicity. Therefore, the bioavailability via the dermal route is not clear, but regarding the physico-chemical properties of the substance a dermal absorption could be assumed. However, as N-ethylpropylamine is also caustic and might therefore lead to destruction of membrane barriers. The existing data indicate that corrosion and irritation of the respiratory tract (local effects) are the primary effect.

 

With the low molecular weight and the good water solubility N-ethylpropylamine is mainly excreted via urine.