The vast majority of reactions to hair-dye products are caused by PPD. [4–6] In past years, PPD was used in permanent hair dyes but not in semipermanent dyes. More recently, PPD has been used in ...
"This cut and color feels bolder and yet somehow lighter ... and debuted a sassy bob in May 2024, a month after she dyed her hair blue to enter what she dubbed her "Jedi era." ...