Three-generation reproduction study of rats given 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in the diet

Autor: F.J. Murray, B.A. Schwetz, R.J. Kociba, K.D. Nitschke, Charles G Humiston, F.A. Smith
Rok vydání: 1979
Předmět:
Zdroj: Toxicology and applied pharmacology. 50(2)
ISSN: 0041-008X
Popis: A three-generation reproduction study was conducted to evaluate the effects of chronic, low-level ingestion of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Sprague-Dawley rats were maintained continuously on diets providing dose levels of 0, 0.001, 0.01, or 0.1 μg TCDD/kg/day. No significant toxicity was noted in the f0 rats of either sex during the 90 days of TCDD ingestion prior to mating. Significant decreases in fertility and neonatal survival were observed in the f0 generation rats receiving 0.1 μg TCDD/kg/day; these effects precluded continuation of this high dose level in subsequent generations. At 0.01 μg TCDD/kg/day, fertility was significantly decreased in the f1 and f2 but not f0 generations. Other indications of toxicity seen at 0.01 μg TCDD/kg/day included decreases in litter size at birth, gestation survival (proportion of pups born alive), and neonatal survival and growth. Among the rats receiving 0.001 μg TCDD/kg/day, no effect on fertility, litter size at birth, or postnatal body weight was observed in any generation. No consistent effect on neonatal survival was observed at 0.001 μg TCDD/kg/day. In summary, the reproductive capacity of rats ingesting TCDD was clearly affected at dose levels of 0.01 and 0.1 μg TCDD/kg/day, but not at 0.001 μg TCDD/kg/day, through three successive generations.
Databáze: OpenAIRE