Head-space gas-chromatographic analysis of vinyl chloride monomer in rat blood and tissues.

1. A method for measuring vinyl chloride monomer (VCM) concn. in rat blood and tissues is described, using a head-space g.l.c. technique with flame ionization detector. The method is sensitive to 5 ng/ml VCM in blood and 30 ng/g in tissues. 2. VCM disposition was determined in rat blood, liver, kidney, brain and lung at different intervals after administration of 1--10 mg VCM/kg i.v. and 10 mg/kg orally. 3. VCM distributed rapidly in the organism after i.v. administration; it was eliminated rapidly and was no longer detectable at 15 min for the highest dose and at 4 min for the lowest. VCM was absorbed rapidly when given orally and tissue concn. were measurable for longer than after i.v. treatment. For both routes, VCM concn. in liver and lung decrease faster than in other organs, suggesting that these organs play a role in VCM elimination.

Effects of vinyl chloride exposure alone and in combination with trypan blue--applied systematically during all thirds of pregnancy on the fetuses of CFY rats.

Vinyl chloride (VC) has been shown to be present in the fetal and maternal blood as well as in the amniotic fluid after the exposition of pregnant CFY rats to VC at an atmospheric concentration of 5500, 18 000 or 33 000 mg/m3 (approximately 2000, 7000 or 12 000 ppm) for 2.5 h on the 18th day of pregnancy, indicating the permeability of the placenta to the agent. Teratological investigation of the offspring of pregnant rats exposed continuously to VC at an atmospheric concentration of 4000 mg/m3 air (1500 ppm) during the first, second or last third of pregnancy has shown that VC has no teratological effect in the rat and has no embryotoxic effects either, when applied during the second or last third of pregnancy in the above concentration. Exposition to VC during the first third of pregnancy resulted in an increased fetal mortality and in the manifestation of embryotoxic effects. Fetal losses and induction of central nervous system malformation due to trypan blue administration were not potentiated by a combined exposure of pregnant rats to VC and the dye.

A statistical assessment of the quantitative uptake of vinyl chloride monomer from aqueous solution.

The presence of vinyl chloride monomer (VCM) in foodstuffs and its demonstrated carcinogenic potential when administered by the oral route has raised questions concerning the quantitative estimation of the safety of the use of food packaging fabricated from rigid polyvinyl chloride. A statistical model, which was tested by curve-fitting data obtained from an oral uptake study, has been demonstrated to be of predictive value. Ninety-five percent condifence limits were also calculated, and the data from this study were compared with those from a previous gas phase exposure study. It was concluded that if the total daily liquid intake contained 20 ppm of VCM then the area generated under the blood level-time curve, for rats, would be equivalent to an inhalation exposure of about 2 ppm for 24 hr.