A new study “fits well” with this overall study, said Alexis Temkin, a toxicologist at the nonprofit Environmental Working Group in Washington, DC
It links the use of hair products to hormonal differences that are consistent with some of the health effects associated with such products, Temkin says.
Findings – published in the journal Environmental research – are based on 1,070 pregnant women in Puerto Rico who received three study visits during their pregnancy. They filled out questionnaires about personal use of the product and provided blood samples to measure hormone levels.
Overall, estrogen, progesterone, and testosterone levels were lower among women who reported using “other” hair products, compared to those who did not. This category includes dyes, straighteners, bleaches and foams, but not shampoos, conditioners, hairspray or hair gel.
It is not clear, according to Rivera-Nunez, whether women who use these hair products may be exposed to certain chemicals that are problematic, or have a higher level of exposure to endocrine disruptors.
In addition, there are many factors that can affect pregnancy hormones. The researchers took into account variables they could – such as women’s body weight before pregnancy, income and level of education, as well as their history of smoking and drinking.
But it is not possible to explain everything, Rivera-Nunez said.
For now, she has recommended that women who are pregnant or planning a pregnancy read labels and be aware of what they are putting on their body. She also acknowledged that these labels are not necessarily tailored to consumers.
“Lack of good labeling is a problem,” Rivera-Nunez said.
Temkin advised you to watch out for the word “smell” – a term that sounds harmless and that actually includes a wide range of undiscovered chemicals, some of which can be endocrine disruptors.
The Working Group on the Environment has more on personal care product ingredients.
SOURCES: Zorimar Rivera-Nunez, PhD, MS, Assistant Professor, Biostatistics and Epidemiology, Rutgers School of Public Health, Piscataway, NJ; Alexis Temkin, Ph.D., Toxicologist, Environmental Working Group, Washington, DC; Environmental research, November 17, 2021, online