Hair straightening products contain chemicals called phthalates. Also known as "plasticizers," phthalates are added to hair straighteners to relax the hair and create a softer feel.
Yet phthalates are dangerous. Multiple studies have shown that phthalates can disrupt the endocrine system - the parts of the body that manage hormone production and uptake.
While the effects of phthalate exposure vary depending on the type and amount of phthalates involved, endocrine disruption from phthalate exposure has been linked to many hormone-related problems, including a higher risk of uterine cancer.