Delayed effects of neonatal exposure to Tween 80 on female reproductive organs in rats.

Neonatal female rats were injected ip (0.1 ml/rat) with Tween 80 in 1, 5 or 10% aqueous solution on days 4-7 after birth. Treatment with Tween 80 accelerated maturation, prolonged the oestrus cycle, and induced persistent vaginal oestrus.

Subacute immunotoxicity study of formaldehyde in male rats.

Immune functions were examined in male rats following 28 day oral administration of formaldehyde by gastric tube at dose levels of 0, 20, 40, and 80 mg/kg. Routine parameters examined included hematology, clinical chemistry, and body, thymus, kidney, and liver weights. In addition, cellularity of spleen and lymph nodes, histology of spleen, thymus, lymph nodes, liver kidney, small and large intestines, and histochemistry of spleen and lymph nodes were evaluated.

[The estrogenic effect of the fungicide Novozír MN 80 on the uterus in neonatal rats].

The estrogenic effect of the ethylenebisdithiocarbamate fungicide Novozír MN 80 (Duslo, Sal') was studied by means of the screening method determining the reproductive risk of chemical substances, recommended by the Environmental Protection Agency. Compared to intact controls, a significant increase in relative uterine weight was recorded in the group of animals which received 1/25 of the maximal tolerable concentration of Novozír MN 80. Compared to negative controls (Tween 80), the relative uterine weight was increased significantly after administration of 1/25 and 1/50 of the maximal tolerable concentration of Novozír MN 80.

Combined chronic toxicity/carcinogenicity study of the fungicide trimorphamide in rats.

Trimorphamide, a new fungicide, was fed over 2 years to groups of 50 male and 50 female rats at dietary levels of 0, 67, 330 and 665 mg/kg. No adverse effects on mortality, haematology, urinalysis, organ weights, incidence and severity of tumors were observed. Isolated observations of abnormalities in blood chemistry suggested the possibility of certain renal damage in the highest dosage group; however, the clinical significance of these findings is dubious.

On the mechanism of acute toxicity of phosmet.

Rats were given single oral doses of phosmet (LD50 or 3/4 LD50). Changes of hematological parameters were studied in several time intervals; the main interest was paid to disturbances in blood clotting. Both light and electron microscopy were used to evaluate histopathological changes in selected organs (liver, lungs, spleen, stomach).