The interactive Web site, called “Critical Windows of Development,” has compiled an array of data from hundreds of scientists studying low doses of endocrine-disrupting chemicals. “By making it electronic, the worldwide availability is a tremendous step forward in data dissemination.” The Web site compiles information from hundreds of studies and inserts it on timelines that show the development of key bodily systems in both people and animals, including the male and female reproductive tracts, immune system and nervous system.

By layering research results over these timelines, Colborn provides graphic evidence. She said her intent is to give scientists, policymakers, journalists and others immediate access to the information in a user-friendly, visually interesting way. “This puts information directly at our fingertips with the utmost ease,” said Jacklin Prins, a physiology professor at University of Illinois at Chicago and one of a few dozen scientists who have previe the Web site. An electronic database going public today has gathered the latest science on some of the most controversial chemicals in use, offering a handy look into potential health effects when babies are exposed while developing in the womb.

Theo Colborn, a scientist often credited with discovering in the delmer 1990s that environmental pollutants were mimicking and altering hormones, led the effort to create the database.