Cancer-causing chemicals in hair straighteners and hair relaxers have been linked to uterine (endometrial) cancer and ovarian cancer. Women who have regularly used chemical hair straighteners and hair relaxers and have developed uterine or ovarian cancer are filing lawsuits.
Cancer-causing chemicals and substances used in hair straighteners include:
This is only a partial list of some of the cancer-causing chemicals and substances that have been found in chemical hair straighteners and relaxers. These chemicals are known as endocrine-disrupting chemicals, because they disturb the functions of the endocrine system, which regulates the body’s production of hormones.
The endocrine system regulates the body’s production of hormones, which are the body’s chemical messengers. Glands in our bodies secrete hormones into the bloodstream. The major endocrine glands are the adrenal glands, the pancreas, and the pineal, pituitary, thymus, and thyroid glands. People also produce hormones in their ovaries or testes.
Hormones work slowly and affect many different bodily processes and aspects, including:
Hormones are powerful. A small amount of hormones can effect big changes in individual cells or even throughout the body. That is why too much or too little of a hormone can cause serious problems.
Endocrine-disrupting chemicals (EDCs) disturb the functions of the endocrine system. EDCs are chemicals or chemical mixtures that interfere with the way hormones work.
Even low amounts of EDCs may be unsafe. As noted, the body’s normal endocrine functioning involves very small changes in hormone levels causing significant biological and developmental effects. Disruptions to the endocrine system and to the body’s hormone levels can have serious consequences. Exposure to EDCs has been linked to numerous adverse health outcomes, including certain types of cancer.
People may be exposed to endocrine-disrupting chemicals through the air they breathe, food they eat, and water they drink. EDCs can also enter the body through the skin, such as when hair straightening chemicals containing EDCs are applied to a person’s scalp.
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