Registration Dossier

Administrative data

Link to relevant study record(s)

Description of key information

No specific toxicokinetic data are available, either for the entire mixture or for single key constituents of the substance ‘Naphtha (petroleum), steam-cracked, C8-10 aromatic hydrocarbon fraction, alkylated and oligomerised’ (NAF-AO) [EC no. 701-299-7] (see Chap. 1). Toxicokinetics (ADME) are expected to follow general scientific rules.

Key value for chemical safety assessment

Additional information

No quantitative information can be provided. However, given the low to moderate molecular masses (from about 230 (dimers) over 360 (trimers)) to < 500 (tetramers)) along with their lipophilic nature, the dimeric and trimeric, but also the tetrameric fractions of NAF-AO are principally bioavailable via the gastro-intestinal route to some extent. They are likely to be metabolised to variable degree in the liver to more water-soluble species that can be excreted into the urine, or released into the bile and faeces changed or unchanged, but also be able to enter the circulatory system with the unchanged portion able to distribute to adipose tissue. Major metabolic sites (oxidative transformation) will be the aromatic rings and the methyl substituents as well as other sites on the alkyl/alkenyl chains.

Similar to related arylaromatic structures, they are unlikely to accumulate, at least at low exposure levels.

Penetration into and through the skin can be anticipated, too, due to the small molecular size and lipophilicity; however, this is likely to happen distinctly less than after oral ingestion due to the barrier function of the cutis.