Safety evaluation and biochemical behavior of monotertiarybutylhydroquinone

Abstract

The safety of monotertiarybutylhydroquinone as an oil‐soluble food grade antioxidant was evaluated in acute studies with rats and dogs, in subacute feedings in rats, in rat reproductive efficiency and placental transfer studies, and in subacute feedings with monotertiarybutylhydroquinone heated in vegetable oil. In lifetime feedings in rats and 2 year feedings in dogs, wt gain, feed consumption, behavior, mortality, hemograms, clinical chemistries, gross, microscopic, and electron microscopy were evaluated. There were no toxic or untoward effects. Monotertiarybutylhydroquinone was handled similarly by rats, dogs, and humans. Rats eliminated single oral 0.1–0.4 g/kg doses mostly in the urine in 3–4 days as the 4‐0‐sulfate (57–80%) and the 4‐0‐glucuronide (4%) and with 4–12% unchanged. 2,3,5,6‐14C‐Monotertiarybutylhydroquinone was eliminated similarly with <0.1% as14CO2 and <0.2% remaining in the animal after 4 days. Oral 0.1 g/kg doses to dogs gave a somewhat higher glucuronide contribution. The elimination pattern was little altered in long term feedings. Humans eliminated 0.002 g/kg single doses (high fat vehicle) almost completely in the urine in 2–3 days, with <0.1% unchanged, 73–88% as the 4‐0‐sulfate, and 15–22% as the 0‐glucuronide. Monotertiarybutylhydroquinone residues in most tissues of long term animals were below lower detection limits or negligible. Monotertiarybutylhydroquinone did not induce liver microsomal mixed function oxidases in short and long term rat and dog feedings. The feeding studies and comparative biochemical studies showed monotertiarybutylhydroquinone to be safe for its intended use.

Determination of Tertiary‐butylhydroquinone and Its Metabolites in Rat Serum by Liquid Chromatography–Ion Trap Mass Spectrometry

“…5d1) showed that a major product ion was m/z 165 (from loss of C 6 H 6 O 6 ), the other product ion were m/z 175, a characteristic product ion of glucuronide conjugates [15], and m/z 113 (the loss of CO 2 The results indicate that besides free TBHQ, TBHQ is mainly metabolized to a TBHQ-sulfate, a TBHQ-glucuronide and two derivatives from TBHQ-sulfate in rat serum after oral administration. These findings are consistent with those results reported in the literature [13,16]. Astill et al reported that 57-74% of the administered TBHQ was eliminated in the urine as the sulfate conjugate.…”

Thermal decomposition of some phenolic antioxidants

“…The phenolic compounds, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), propyl gallate (PG) and tert-butylhydroquinone (TBHQ), originally developed for petroleum protection, were authorized in the United States as antioxidants for use in food (Marino and Mitchell, 1972;Pascal;1974, Astill et al, 1975Branen, 1975;Saheb and Saheb, 1977; Hansen and Meyer, 1978; Porter, 1987). The addition of these compounds is subject to government regulations and varies with type of food.…”

Alteration of phenolic antioxidants in heated vegetable oil

“…Phenolic antioxidants such as BHA, BHT, TBHQ and propyl gallate play an important role in the manufacturing, packaging and storage of fats and fatty foods. These compounds have undergone extensive toxicological evaluations (1)(2)(3)(4)(5)(6) and, in general, they show low orders of toxicity in laboratory animals. As mandated in the Food, Drag and Cosmetic Act, the addition of these antioxidants, alone or in combination, is limited to 0.02% by weight of the fat or oil content of the food (7).…”