Comparative aspects of the reproductive toxicology by inhalation in rats of ethylene glycol monomethyl ether and propylene glycol monomethyl ether.

This study was designed to provide a rapid assessment of the effect of two glycol ethers on some aspects of reproduction in the rat. Exposure was by inhalation at 100 and 300 ppm (EGME) and 200 and 600 ppm (PGME) for 6 hr/day. The study was in two parts: (a) Pregnant females were exposed on Days 6 to 17 of gestation. Body weight gain was reduced in both EGME groups. No litters were delivered in the 300-ppm EGME group and only 9/20 rats in the 100-ppm EGME group produced litters where the number, weight, and viability of the pups were reduced, but the pups appeared normal externally. Exposure at 200 and 600 ppm PGME had no effect. (b) Male rats were exposed for 10 days. There was a reduction in testicular weight accompanied by semeniferous tubular atrophy in the 300-ppm EGME group. There were no effects at 100 ppm EGME or 200 and 600 ppm PGME. 300 ppm EGME caused significant reductions in white blood cell count, red blood cell count, hemoglobin concentration, hematocrit, and mean cell hemoglobin. The study design proved capable of demonstrating the effects of EGME on the testes and on fetal development and highlighted PGMEs lack of activity at the doses tested.