The Greenguard Environmental Institutetests materials and products for chemical emissions. Greenguard is a helpful resource for selecting appropriate products.
This link will take you to Greenguard's product selection guide for shades.
For more information:
Read "Can you recommend solar window blinds that are not made of PVC?" a Q&A answered by Maggie Wood.
We also recommend the article "I am looking for window treatments for my 2-year-old's room. What will keep her environment healthy and block light?" by Neil Gordon.