Much maligned ingredients week

When this series on preservatives ends on November 4th, I'm planning a week of much maligned ingredients week, including propylene glycol and mineral oil, and some of those on the Suzuki Foundation's list. Since I tend to be out of the loop about what's bad this week, I'm looking to you - my amazing readers - to let me know what concerns you! Comment below on what you'd like to see researched!