Dermal absorption of phthalate diesters in rats

Journal Article · Sun Jan 01 00:00:00 EST 1989 · Fundam. Appl. Toxicol.; (United States)

DOI:https://doi.org/10.1016/0272-0590(89)90063-8· OSTI ID:5985545

Elsisi, A E; Carter, D E; Sipes, I G

This study examined the extent of dermal absorption of a series of phthalate diesters in the rat. Those tested were dimethyl, diethyl, dibutyl, diisobutyl, dihexyl, di(2-ethylhexyl), diisodecyl, and benzyl butyl phthalate. Hair from a skin area (1.3 cm in diameter) on the back of male F344 rats was clipped, the (14C)phthalate diester was applied in a dose of 157 mumol/kg, and the area of application was covered with a perforated cap. The rat was restrained and housed for 7 days in a metabolic cage that allowed separate collection of urine and feces. Urine and feces were collected every 24 hr, and the amount of 14C excreted was taken as an index of the percutaneous absorption. At 24 hr, diethyl phthalate showed the greatest excretion (26%). As the length of the alkyl side chain increased, the amount of 14C excreted in the first 24 hr decreased significantly. The cumulative percentage dose excreted in 7 days was greatest for diethyl, dibutyl, and diisobutyl phthalate, about 50-60% of the applied 14C; and intermediate (20-40%) for dimethyl, benzyl butyl, and dihexyl phthalate. Urine was the major route of excretion of all phthalate diesters except for diisodecyl phthalate. This compound was poorly absorbed and showed almost no urinary excretion. After 7 days, the percentage dose for each phthalate that remained in the body was minimal and showed no specific tissue distribution. Most of the unexcreted dose remained in the area of application. These data show that the structure of the phthalate diester determines the degree of dermal absorption. Absorption maximized with diethyl phthalate and then decreased significantly as the alkyl side chain length increased.

• Research Organization: Univ. of Arizona, Tucson (USA)
• OSTI ID: 5985545
• Journal Information: Fundam. Appl. Toxicol.; (United States), Vol. 12:1
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
59 BASIC BIOLOGICAL SCIENCES
PHTHALIC ACID
SKIN ABSORPTION
CARBON 14 COMPOUNDS
ESTERS
METABOLISM
MOLECULAR STRUCTURE
RATS
TISSUE DISTRIBUTION
TRACER TECHNIQUES
ABSORPTION
ANIMALS
CARBOXYLIC ACIDS
DICARBOXYLIC ACIDS
DISTRIBUTION
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
MAMMALS
ORGANIC ACIDS
ORGANIC COMPOUNDS
RODENTS
UPTAKE
VERTEBRATES
560300* - Chemicals Metabolism & Toxicology
550501 - Metabolism- Tracer Techniques