Many hair products used by black women and children contain chemicals that can interfere with the body’s natural hormones, though the majority of these chemicals are not listed on their labels, according to new research forthcoming in the journal Environmental Research.
These chemicals, including parabens, fragrances and phthalates, are found in many consumer products. They are known as endocrine-disrupting chemicals (EDCs) because they disturb the functions of the endocrine system, which regulates the body’s production of hormones.
They do this by mimicking the body’s naturally occurring hormones, which can overstimulate cells; they can also block naturally occurring hormones from binding to cells’ receptors, or alter the metabolism of natural hormones. Disruptions to the endocrine system can lead to the development of hormone-mediated diseases like obesity, diabetes and certain types of cancer.
Other research suggests that differing personal product care usage might explain these elevated rates of endocrine-disrupting chemicals (EDCs) in black women, which might in turn contribute to the noted health disparities.
With this in mind, scholars at the Silent Spring Institute and Battelle Memorial Institute — non-profit organizations that research environmental chemicals and science and technology, respectively — set out to document the extent to which endocrine-disrupting chemicals are present in hair products used by black women and children.
They focused their research on cataloguing the concentrations of 66 endocrine-disrupting chemicals in 18 popular hair products. The products spanned six categories, including hot oil treatments, relaxers, hair lotions, leave-in conditioners, root stimulators and anti-frizz products.
They selected the products based on survey results that indicated the most frequently used products among black women, along with products used by black women, but not others. The products were first purchased for research in 2008 and the scholars note that their formulations might have changed since.
However, they write that more recent comparisons indicate that most of the products list the same ingredients as before.
They found:
In addition to the temporal limitation noted, the study is also limited in that it only documents the concentrations of EDCs in 18 products used by black women.
Further, the researchers did not study all the chemicals in these products that might have health effects, instead focusing on chemicals with established links to the endocrine system and asthma.