Critical Windows of Development was created by Theo Colburn, who is most often credited with the discovery of hormone mimicking chemicals, stating that she created the site as a way to “give scientists, policymakers, journalists and others immediate access to the information in a user-friendly, visually interesting way.”

When a Critical Windows user chooses a chemical, red lines appear on a timeline, displaying the areas of development where effects have been found in laboratory animals exposed to low doses. Clicking on a triangle retrieves a summary of each study, which then leads to direct access to the published article in a scientific journal.

The site shows how normal development should occur versus results obtained in lab results of development in the presence of these various chemicals, like BPA and phthalates.  It does focus on human gestation and compares to results found in mice gestation.

The site has links to where you can get the latest news, how you can contact the EPA and other agencies to ask for change, and all the definitions of the chemicals and the products they can be found in.  This is seriously the most comprehensive site for anyone concerned about the health of their babies and the impact from environmental factors. 

To read more about how to interpret results, please go to Environmental Health News.