Registration Dossier

Administrative data

Link to relevant study record(s)

Description of key information

2-butyl-2-ethylpropanediol (BEPD) is likley to be rapidly and extensively absorbed following oral and dermal exposure, with absorption following dermal exposure less extensive and more prolonged.  Extensive distribution in body fluids is predicted. BEPD is likely to be metabolised by sequential oxidation of the hydroxy grops and excreted rapidly in the urine.  Bioaccumulation is unlikely.

Key value for chemical safety assessment

Bioaccumulation potential:
no bioaccumulation potential
Absorption rate - oral (%):
50
Absorption rate - dermal (%):
50
Absorption rate - inhalation (%):
100

Additional information

No toxicokinetic data are available. An adequate assessment of the basic toxicokinetics of 2-butyl-2-ethylpropanediol (BEPD) can be made from the existing toxicity data and theoretical considerations, without the need for specific testing, in line with the REACH data requirements.

Absorption

Extensive oral absorption of 2-butyl-2-ethylpropanediol is predicted based on its molecular size, solubility, chemical structure and on the basis of experience with other alcohols. The 2-butyl-2-ethylpropanediol molecule additionally satisfies Lipinski's rule of 5 (OECD QSAR Toolbox). Oral absorption is demonstrated by the findings of the acute oral toxicity study and systemic effects in the 28 -day oral study. Absorption following inhalation exposure is also likely to be extensive. Dermal absorption is likely to be less extensive, but is likely to occur to some extent. The results of the acute dermal toxicity study support this theory.  In the absence of any quantitative absorption data, default assumptions are made for the purposes of DNEL calculation.

Distribution

No data are available, however rapid and extensive distribution can be predicted based on the knowledge of other low molecular weight alcohols. Effects in the 28 -day adn 90 -day studies indicate distribution of BEPD and/or its metabolites to the liver and kidneys.

Metabolism

Sequential oxidative metabolism of the hydroxy groups is predicted, based on known metabolic reactions and the elucidated pathways for other alcohol compounds. The OECD QSAR Toolbox (liver metabolism simulator) predicts a total of 2 metabolites. Hepatic metabolism is indicated by the adaptive effects (hepatocyte hypertrophy) noted at high dose levels in the 28 -day study.

Excretion

Rapid and extensive renal excretion of 2-butyl-2-ethylpropanediol and its metabolites is likely, with no potential for bioaccumulation based on chemical properties and likely extensive metabolism. Renal excretion is indicated by effects seen at high dose levels in the 28 -day and 90 -day studies.