A new study by NIEHS scientists finds that chronic exposure to lavender products is associated with earlier breast development in girls, and the findings also identify chemicals in lavender and tea tree oils as potential endocrine disruptors that have various effects on the receptors for the two hormones estrogen and androgen (see sidebar). study On August 8th Endocrine SocietyJournal of Clinical Endocrinology and Metabolism.
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“These findings demonstrate that the two oils may have hormone-like effects on estrogen and testosterone in the body,” said senior author Kenneth Kolac, PhD, principal investigator in the NIEHS Receptor Biology Group. “Lavender oil and tea tree oil may raise concerns about potential health exposures that require further study, especially since these oils are available without a prescription from a health care professional and are not regulated by the Food and Drug Administration.”
Unsafe alternatives?
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Lavender oil and tea tree oil The most popular essential oils The majority of natural substances used today are natural. “In our society, essential oils and other therapeutic agents are viewed as safe alternatives to medicine, personal hygiene, aromatherapy, and cleaning products,” said Tyler Ramsey, a postgraduate researcher in Kolac’s team and lead author of the paper. “However, there are many natural substances that can have effects on the human body, similar to some synthetic drugs.”
in Previous researchDr. Kolac and his team have shown that exposure to lavender and tea tree oils is associated with gynecomastia, or abnormal breast development, in prepubertal males. Building on these findings in the new study, the team has also found that exposure to lavender-scented products is associated with a condition called premature breast development, which occurs in girls under the age of eight and occurs without other signs of puberty.
Over a seven-year period, the clinician colleagues identified 24 patients who were seen for prepubertal gynecomastia, or premature gynecomastia, at Nicklaus Children’s Hospital in Miami, Florida. Of these patients, five girls and 11 boys had been exposed to lavender-scented products, including cologne, shampoo, and soap. An additional four girls seen for premature gynecomastia at the University of California, Irvine or CHOC Pediatric Clinic in Orange County, California, also used lavender-scented products.
One girl who bathed with soap containing lavender oil from an early age showed signs of breast development by age 1. Another girl showed signs of breast development after a year of exposure to a lavender oil diffuser that ran all day on a nearby teacher’s table. One boy and three girls in case reports experienced involution of breast tissue within six months of ceasing exposure to lavender-scented products.
Potential endocrine disruptor
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To explore the underlying mechanisms, Kolac and his team investigated the effects of eight compounds found in lavender and tea tree oils. Some of the ingredients had varying degrees of estrogenic or anti-androgenic properties, as determined by their effects on estrogen receptor alpha and androgen receptor activity in human cells. The findings suggest that compounds found in essential oils may promote breast growth by enhancing estrogenic activity while suppressing androgenic activity.
Ramsey was originally These results were published The study was presented at the Endocrine Society’s 100th Annual Meeting in March 2018. Many of the chemicals tested were also reported to be present in more than 65 other essential oils.
“It is important that physicians are aware that lavender oil and tea tree oil have endocrine-disrupting effects. Although the effects we saw are very rare, such oils should be considered when evaluating unexplained early breast development in girls and gynecomastia in boys and adult men,” Colac said. “The public should take these experimental results into consideration, and if it is determined that there is a potential causal relationship, they may decide it is best to discontinue use.”
Quote:
Ramsey JT, Lee Y, Alao Y, Naidu A, Kuhn LA, Dias A, Korak KS.2019. Association of lavender products with premature breast development and prepubertal gynecomastia: case report and EDC activity. J Clin Endocrinol Metab; doi:10.1210/jc.2018-01880 [Online 8 Aug 2019].
Dolnick N, Fisch AS, Rood AC, Sabouraud D, Ezzedine K2016. Aromatherapy use patterns in the French general population: a descriptive study focusing on dermal exposure. Regul Toxicol Pharmacol 76:87–93.
Henry DV, Lipson N, Korachi KS, Bullock CA.2007. Association of lavender oil and tea tree oil with prepubertal gynecomastia. N Engl J Med 356(5):479–85.
(Dr. Janelle Weaver is a contract writer for the NIEHS Office of Public Affairs and Communications.)