ESTP comments on the draft updated OECD test guideline 407.

The revision of the OECD TG 407 test guideline (repeated dose 28-day oral toxicity study in rodents) focuses on endpoints to detect endocrine activities of chemicals. The new endpoints are likely to influence other previously established core endpoints of this study type. An expert group of pathologists and toxicologists within the European Society of Toxicologic Pathologists (ESTP) has contributed to the scientific discussion of the draft guideline.

Sensitive detection of the endocrine effects of the estrogen analogue ethinylestradiol using a modified enhanced subacute rat study protocol (OECD Test Guideline no. 407).

Groups of five male and female Wistar rats were treated by gavage with 0, 0.01, 0.05 or 0.