Distribution, excretion, and metabolism of butylbenzyl phthalate in the rat

Journal Article · Tue Dec 31 23:00:00 EST 1985 · J. Toxicol. Environ. Health; (United States)

DOI:https://doi.org/10.1080/15287398609530839· OSTI ID:5810310

Eigenberg, D A; Bozigian, H P; Carter, D E; Sipes, I G

The disposition of butylbenzyl phthalate (BBP), a widely used plasticizer, was evaluated after oral and iv administration to rats. Male Fischer-344 rats were dosed with (/sup 14/C)BBP at 2, 20, 200, or 2000 mg/kg po or 20 mg/kg iv to determine the effects of dose on rates and routes of excretion. In 24 h, 61-74% of the dose was excreted in the urine and 13-19% in the feces at 2-200 mg/kg. At the 2000-mg/kg dose, 16% of the /sup 14/C was excreted in the urine and 57% in the feces. Urinary /sup 14/C was composed of monophthalate derivatives (MP: 10-42% of the dose) and glucuronides of these monophthalate derivatives (2-21% of the dose). At 4 h after iv administration of BBP (20 mg/kg), 53-58% of the dose was excreted in the bile of anesthetized rats. No parent compound was found in the bile, but monobutyl phthalate-glucuronide and monobenzyl phthalate-glucuronide (26% and 13% of the dose, respectively) and trace amounts of free monoesters (2% of the dose) and unidentified metabolites (14% of the dose) were present. Although BBP is an asymmetric diester with the potential of forming equal amounts of monbutyl phthalate (MBuP) and monobenzyl phthalate (MBeP), larger quantities of MBuP were formed (MBuP = 44% versus MBeP = 16% of the dose). The half-lives of BBP, MP, and total /sup 14/C in blood (20 mg/kg, iv) were 10 min, 5.9 h, and 6.3 h, respectively. This study indicates that BBP is rapidly metabolized and that the major route of excretion of metabolites is biliary. These metabolites are reabsorbed and ultimately eliminated in the urine.

• Research Organization: Univ. of Arizona, Tucson
• OSTI ID: 5810310
• Journal Information: J. Toxicol. Environ. Health; (United States), Journal Name: J. Toxicol. Environ. Health; (United States) Vol. 17:4; ISSN JTEHD
• Country of Publication: United States
• Language: English

Related Subjects

550501* -- Metabolism-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ANIMALS
BILE
BIOLOGICAL MATERIALS
BIOLOGICAL WASTES
BLOOD
BODY FLUIDS
CARBON 14 COMPOUNDS
CLEARANCE
DISTRIBUTION
ESTERS
EXCRETION
FECES
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
MAMMALS
MATERIALS
METABOLISM
METABOLITES
ORGANIC COMPOUNDS
PHTHALIC ACID ESTERS
RATS
RETENTION
RODENTS
TISSUE DISTRIBUTION
TRACER TECHNIQUES
URINE
VERTEBRATES
WASTES