After a stinky Brazillian hair straightening treatment, best friends Alexandra Spunt and Siobhan O’Connor started to wonder what exactly was in this miraculous chemical agent. They started doing the research, and were horrified by what they found. They were determined to make sure that people were aware of what they uncovered.

And they did what any good samaritan would do.

They wrote a book.

No More Dirty Looks: The Truth about Your Beauty Products--and the Ultimate Guide to Safe and Clean Cosmetics

Q. What  was your inspiration for this project?

A. Siobhan: We went for a hair treatment together called the Brazilian blowout only to discover that the active ingredient was formaldehyde—a known carcinogen!

Alexandra: We couldn’t understand how that was possible, let alone legal. And so the research began.

Q. How did you find the process of writing the book? It looks like there is so much info out there on how yucky most of these products are–how were you able to self-edit what was in and what was out?

A. Alexandra: There’s definitely a lot of information out there — probably enough for another book! — but filtering it (and verifying it) is our job. We love that stuff. It also helped to have each other as sounding boards, not to mention our wonderful editor Katie McHugh at Dacapo Lifelong.

Q. What advice do you have for people?

A. Alexandra: Read our book! Not only because we want to sell it, but because we’ve done a lot of the legwork for people… We’ve spent hours trolling medical databases, testing products, reading ingredients lists and interviewing experts.

Siobhan: Another piece of advice: Don’t get overwhelmed. You don’t have to throw out all your products at once, just start with the ones you’re least attached to and that cover the largest surface area (i.e. your body cream).

Q. What have you learned from from all this?

A. Alexandra: We learned that our skin is our biggest organ and that it absorbs up to 60% of what goes on it.

We learned that the cosmetics industry is self-regulated and doesn’t have to prove that their products are safe before they go to market.

Siobhan: On the plus side, we also learned that clean cosmetics work better because they’re not filled with cheap synthetic ingredients but actually contain things that are nourishing and compatible with skin.

Q. What are your future plans and how will this project evolve in coming months?

A. Alexandra: Right now we’re writing everyday on our blog and doing a weekly series for GOOD magazine . It’s really exciting to be getting this message out there—and for now that’s the priority.

Siobhan: We feel pretty blessed to be doing something that we believe in—also we get to talk about fun, girly stuff everyday. With each other no less. It’s a best of all worlds scenario.