Rutgers flags personal care chemicals that disrupt hormone levels in pregnancy following Puerto Rico study

15 Dec 2021 --- A study conducted by Rutgers has found that some personal care products contain ingredients that impact maternal hormone levels. This has implications for fetal health and future child development. The research discovered chemicals such as parabens, phthalates, phenols and toxic metals were present in standard cosmetic products. Each of the aforementioned can disrupt human endocrine and hormone systems, whose functions are crucial during pregnancy, flags the research.

The researchers found that the use of certain hair products in particular were associated with lower levels of sex steroid hormones. This was true for some bleaches, dyes and hair relaxers. A disruption in sex steroids levels can result in preterm birth, low birth weight, and restricted growth, according to the research.

The study was funded by the US National Institute of Environmental Health Sciences and the National Institute of Health. The findings may hold significance for future regulations regarding consumer safety and product formulation.

“Alterations in hormone levels, especially during pregnancy, can have vast consequences beyond health at birth including changes in infant and child growth, pubertal trajectories and may influence the development of hormone-sensitive cancers such as breast, uterine and ovarian cancer,” says Zorimar Rivera-Núñez, assistant professor at Rutgers University, and lead author of the study.

The study found that demographic factors predicted usage patterns.Increased risk among wealthier groups
Rivera-Núñez’s team specifically investigated the correlation between personal care product use by pregnant women and their sex hormone levels. The study also explored the impact of demographic variables on product use.

The use of cosmetics increased significantly alongside age, income, and education levels. Those who were employed and those who received a higher income reported using more cosmetics than those who were unemployed or had a low income. 

The fact that certain groups use certain products more often necessarily means that said groups are at a greater risk of pregnancy complications overall. The research team contextualized their results within the scope of culture.  

“A strong culture of beauty influences Latina women, which may impact consistent use of cosmetics through pregnancy. This data is important because it will allow us to identify populations who are at an increased risk of chemical exposures associated with personal care product use,” says Rivera-Núñez.

Research design
The sample group for the study consisted of 1,070 pregnant women in Puerto Rico between 18 to 40 years of age. The average age for the study was 27 ± 5, and most participants were married or in a domestic partnership (77%). The majority of participants had received a high school education (75%), had a job (60%) and had private health insurance (58%). 

Importantly, the overwhelming majority had never smoked (80%), with 2% admitting to smoking during their pregnancy. This is significant, as cigarette smoking can also affect sex hormone levels. 

All were enrolled in the Puerto Rico Test site for Exploring Contamination Threats (PROTECT) cohort. This program is designed to investigate the ongoing effects of environmental exposure to contaminants on pregnant women and their children in Puerto Rico’s Northern Karst region. Hormone disruptions during pregnancy can affect children's development.

After receiving physical examinations, the participants completed a self-report questionnaire asking about their background, occupation, and lifestyle. They were also asked about their use of personal care products, including nail polish, hair relaxers, bleach, mousse, shaving cream, mouth wash, lotions and cosmetics. Researchers also took two blood samples from the participants during pregnancy. 

Moving forward 
The study analyzed the levels of nine sex steroids and thyroid hormones. These were: corticotropin-releasing hormone, sex-hormone binding globulin, estriol, progesterone, testosterone, thyroid-stimulating hormone, total triiodothyronine, total thyroxine and free thyroxine. Each hormone impacts the health of pregnant people and their children. 

The researchers said further investigations into the impact of certain chemicals on pregnant people were necessary. “Additional research should address the public health impact of exposure to chemicals in hair products in pregnant populations,” says Rivera-Nuñez. 

The researchers recommended that care providers and obstetricians take more time to discuss the impact of certain cosmetic and hair care products with their patients. 

Edited by Olivia Nelson