Uptake and distribution of 14C during and following exposure to [14C]methyl isocyanate.
Ferguson-JS; Kennedy-AL; Stock-MF; Brown-WE; Alaire-Y
Toxicol Appl Pharmacol 1988 Jun; 94(1):104-117
The uptake and distribution of methyl-isocyanate (624839) (MIC) were studied in guinea-pigs and mice. Male English-guinea-pigs, some surgically implanted with tracheal, venous, and arterial cannulas, were exposed to 0.5 to 15 parts per million (ppm) carbon-14 (C-14) labeled MIC vapor for 1 to 6 hours. Blood, bile, and urine samples were collected at selected times for up to 3 days and assayed for C- 14 activity. Male and pregnant female Swiss-Webster-mice were exposed to 2.10ppm C-14 labeled MIC for 6 hours. They were killed 2 and 24 hours after exposure ended and the tissue distribution of C- 14 activity was determined. MIC derived C-14 activity was detected in venous and arterial blood within minutes of exposure; however, blood MIC concentrations in animals exposed by way of the tracheal cannula were much lower than in those which breathed normally. MIC was cleared slowly from the blood; most of it was cleared within 3 days. MIC was cleared more rapidly from the urine than from bile. The highest concentrations of MIC in male mice 2 hours after exposure were found in the lung, sternum, gastrointestinal tract, spleen, and kidney. Twenty four hours after exposure, highest MIC concentrations were in the blood and lung. In female mice the highest concentrations at 2 hours after exposure were found in the lung, fetus, spleen, uterus, and kidney. After 24 hours the highest concentrations were in the lung, spleen, and fetus. The authors conclude that inhaled MIC is taken up rapidly in the blood. This uptake is much higher in normal animals than in those breathing through a tracheal tube.
NIOSH-Publication; NIOSH-Grant; Grants-other; Isocyanates; Esters; In-vivo-studies; Laboratory-animals; Tissue-distribution; Sex-factors; Pregnancy; 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