Methylene chloride: a 2-year inhalation toxicity and oncogenicity study in rats.

Male and female Sprague-Dawley rats were exposed to 0, 50, 200, or 500 ppm methylene chloride for 6 hr/day, 5 days/week for 2 years. Blood carboxyhemoglobin levels were elevated in a dose-dependent (less than linear) manner in rats exposed to 50-500 ppm methylene chloride. Histopathologic lesions related to methylene chloride exposure were confined to the liver and mammary tissue of rats.

Chronic toxicity and oncogenicity study on inhaled vinylidene chloride in rats.

Male and female Sprague-Dawley rats (Spartan substrain) were exposed to vinylidene chloride (VDC) by inhalation for 18 months to assess chronic toxicity and oncogenic potential of the subject test material. Interim sacrifices were performed at 1, 6, and 12 months. Rats were exposed to VDC concentrations of 10 and 40 ppm for 6 hr/day, 5 days/week for the first 5 weeks of the study.

Methylene chloride: a two-year inhalation toxicity and oncogenicity study in rats and hamsters.

A long-term study was conducted to determine the possible chronic toxicity and oncogenicity of methylene chloride. Rats and hamsters were exposed by inhalation to 0, 500, 1500, or 3500 ppm of methylene chloride for 6 hr per day, 5 days a week, for 2 years. No exposure-related cytogenetic effects were present in male or female rats exposed to 500, 1500, or 3500 ppm.

Metabolism of acrylate esters in rat tissue homogenates.

Methyl, ethyl and butyl acrylate were hydrolyzed to acrylic acid in rat liver, kidney and lung homogenates. The rates of hydrolysis of the various esters in these in vitro studies were comparable; hydrolysis rates were approximately 20 times higher in liver homogenates than in kidney or lung homogenates. The esters also disappeared rapidly when added to blood in vitro.