If you dye your hair, you may (or may not) be familiar with PPDs. "PPD, or paraphenylenediamine, is a chemical that's common in hair dyes, cosmetics, and in products like photocopying and printing inks," says Carlina Ortega, a colorist at Rita Hazan Salon in New York City.
PPDs are used in these dyes to help produce your color. They don't fade after washing and drying, have low toxicity levels, and can withstand high temperatures. But, some people can be allergic to it — as actress Pauley Perrette found out the hard way recently.
If you fall into the allergy category — or you want to avoid PPDs just in case — there are some options if you want to switch up your hair color. "Most semi-permanent dyes don't contain PPD," Ortega says. She also notes the PPDs are unnecessary when it comes to highlighting hair, so your painted-in ombré won't cause you to break out in a rash. But, if you're looking to get your box dye on sans PPD, we've got you covered.