Uptake and distribution of 14C during and following inhalation exposure to radioactive toluene diisocyanate.
Kennedy-AL; Stock-MF; Alarie-Y; Brown-WE
Toxicol Appl Pharmacol 1989 Sep; 100(2):280-292
The uptake and distribution of carbon-14 (C-14) labeled toluene- diisocyanate (584849) (TDI) was studied in guinea-pigs. Male Hartley-guinea-pigs were subjected to TDI exposure levels ranging from 0.00005 to 0.146 parts per million (ppm). Analysis of the uptake and distribution of radioactivity in the TDI exposed fluids and tissues indicated that some form of the labeled compound, whether TDI, a conjugate, metabolite or hydrolysis product, entered and penetrated throughout the entire system. The rate of uptake into the blood was linear during these exposures and the uptake continued to increase slightly during the post exposure period. Radioactivity cleared from the bloodstream to a level which corresponded to approximately a 100 nanomolar concentration of tolyl group after 72 hours and persisted at a nanomolar level even 2 weeks following exposure. A linear function of the concentration of TDI was also noted for the initial rate of C-14 uptake when expressed either as concentration or as concentration multiplied by duration of exposure. According to the authors, use of this method will allow comparisons to be made of uptake results in blood from one study to another. Comparison of these results to those of previous studies with methyl-isocyanate indicated that the uptake into arterial blood was a function of exposure concentration, independent of isocyanate structure.
NIOSH-Publication; NIOSH-Grant; Grants-other; Isocyanates; Laboratory-animals; Metabolic-study; Inhalation-studies; Body-burden; Tissue-distribution; Blood-analysis
Biological Sciences Carnegie-Mellon University 4400 Fifth Ave Pittsburgh, PA 15213
Other Occupational Concerns; Grants-other
Toxicology and Applied Pharmacology
Carnegie-Mellon University, Pittsburgh, Pennsylvania