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There are no specific studies on Petroleum Gases but data are available on the component substances.

No data were identified following oral or dermal exposure as the Petroleum Gases (C1 to C4 alkanes) are gases at room temperature. Whilst much of the toxicokinetic data identified are cited in secondary literature with insufficient experimental detail, Dahl et al 1988 investigated the comparative rates of uptake of 19 hydrocarbon vapours in the rat. Chemical classes investigated included straight-chain and branched alkanes, alkenes, alkynes, alicyclics, and aromatics and included butane and isobutane. He concluded absorption tends to increase with molecular weight, straight chain molecules are more highly absorbed than branched isomers, and aromatic molecules are more highly absorbed than paraffins. Thus short chain C1-C4 alkanes which exist as a vapour at room temperature, are very poorly absorbed, and if absorbed, are normally rapidly exhaled. Isobutane absorption following inhalation exposure is low (uptake 0.6 -1.0 nmol/kg/min/ppm, lower than butane). Butane absorption following inhalation exposure at 100ppm (240 mg/m3) is low (uptake 1.5 -1.8 nmol/kg/min/ppm) or 0.09 -0.1 micrograms/kg/min/ppm). From this the Health Council of the Netherlands (2004) calculated approx 10% is absorbed.

These data are supported by Daugherty (1988) who reported that ethane absorbed during exposure for 8 h by inhalation is metabolised to carbon dioxide and eliminated in exhaled air. A small proportion (1%) is eliminated in urine.

Haq and Hameli (1980) report a death involving asphyxiation by propane inhalation The rate of propane absorption was reported to be slow, the relative concentration of propane was found in the autopsy to be brain > liver > lung > blood > and kidney specimens, however accurate interpretation of the data are difficult given the likely variability with time of death and time from exposure to testing.

Tsukamoto et al (1985) investigated the metabolism of volatile hydrocarbons. He reported propane is metabolised to acetone and isopropanol in mice inhaling propane for 1 hour, and to isopropanol by mice liver microsomes in vitro; isobutane is metabolised to tert-butanol in mice inhaling isobutane for 1 hour, and by mice liver microsomes in vitro; and n-butane is metabolised to sec-butanol and methyl ethyl ketone in mice inhaling n-butane for 1 hour, and to sec-butanol by mice liver microsomes in vitro.