2-Hydroxyisobutyric Acid (2HIB)

2-hydroxyisobutyric acid (2HIB) is most often the result of exposure to methyl tertiary-butyl ether (MTBE) or ethyl tertiary butyl ether (ETBE), which are gasoline additives used as octane enhancers. MTBE has been found to pollute large quantities of groundwater when gasoline with MTBE is spilled or leaked at gas stations. In addition, MTBE and ETBE are volatile and may be inhaled or absorbed through the skin by drivers during fueling or from exhaust exposure.

MTBE and its metabolites have been shown to be to cause hepatic, kidney and central nervous system toxicity, peripheral neurotoxicity, and cancer in animals. Excretion half-lives in humans range from 10 to 28 hours.

Possible treatment options:

Reduce exposure if possible.

Elimination is accelerated by sauna therapy, by the Hubbard detoxification protocol employing niacin supplementation to aid in MTBE and ETBE excretion, or by treatment with glutathione (reduced) supplementation (oral, intravenous, transdermal, or precursors such as N-acetyl cysteine [NAC]). 2-Hydroxyisobutyric acid is also formed endogenously as a product of branched-chain amino acid degradation and ketogenesis.

High values have been reported in both isovaleric acidemia and multiple acyldehydrogenase deficiency.

2-Hydroxyisobutyric acid is formed endogenously as a product of branched-chain amino acid degradation and ketogenesis. This compound is also the major metabolite of gasoline octane enhancers such as MTBE and ETBE.

MTBE and ETBE are gasoline additives used to improve octane ratings. Exposure to these compounds is most likely due to groundwater contamination, inhalation or skin exposure to gasoline or its vapors, and exhaust fumes. MTBE has been demonstrated to cause hepatic, kidney, and central nervous system toxicity, peripheral neurotoxicity, and cancer in animals. Very high values have been reported in genetic disorders. Because the metabolites of these compounds are the same, ETBE may be similarly toxic.