Some of the substances found in hair products, most commonly used and sold by black and Latino women in particular, are hormone-breaking chemical, said Tamarra James-Todd, an epidemiologist at the Harvard T.H. Han School of Public Health, who was not involved in the new study. But single-handedly led some of the earliest studies to find a link between hair products and cancer.
"They change the normal hormonal processes of our bodies. So it makes sense to look at hormone-mediated cancer, "she said, adding that chemical that disrupt hormones may also affect other parts of the body.
"The challenge is that the effects of these chemical may not be limited to hormonal processes, but may also affect other systems, including our immune and vascular systems. James Todd told CNN that "understanding how these chemical act outside the hormonal system is still a new and growing area of research.".
"So, the way these chemical might work is by altering not just the hormonal response, but by altering the immune response and even the vascular response," she said. "All of these processes are associated with cancer."
Dr. Otis Brawley, a professor at Johns Hopkins Bloomberg School of Public Health and former chief medical officer of the American Cancer Society, said in an email to CNN that while the new study is "well done" and shows a link between hair styling chemical and an increased risk of uterine cancer, it is not possible to determine whether the products directly cause cancer.
"It can't show a cause, it could be a pure association," said Brawley, who was not involved in the new study.
However, "how we solve this problem is difficult. The scientific ideal is a randomized trial of about 40,000 people; 20,000 people regularly use hair straighteners, 20,000 people who have never used hair straighteners and never used them, and follow them for 20 years, "he said, adding that" science can't answer better "than recent research on this point.
ECHEMI --- The name is originated from the abbreviation of “E-commerce of chemical”.
