J. Tyler Ramsey
CHICAGO — Certain chemical components of lavender and tea tree oils have been identified as endocrine-disrupting chemicals and a new study lends further evidence to suggest that topical use in prepubescent boys may lead to the development of male prepubertal gynecomastia.
“There is an increasing popularity of lavender and tea tree oil in our society,” J. Tyler Ramsey, BS, a postbaccalaureate research fellow at the NIH National Institute of Environmental Health Sciences, said during a presentation at the Endocrine Society Annual Meeting. “Some of the previous findings that we’ve seen with lavender and tea tree oil have been linked and determined as endocrine-disrupting chemicals. What that means is that they pose environmental health exposure concerns to the public. Even more so, we’ve seen cases in a lot of clinical settings with the topical exposure of lavender and tea tree oil and the onset of male prepubertal gynecomastia.”
Male gynecomastia occurring before puberty is relatively rare. However, a growing number of cases of prepubertal gynecomastia have been reported to coincide with topical exposure to lavender and tea tree oils, in which the condition went away after the youths stopped using oil-containing products, according to a press release. According to Ramsey, it appears that “abnormal hormone levels are not an explanation for this condition.”
To further study this link, Ramsey and colleagues selected eight common chemical components that comprise lavender and tea tree oils: eucalyptol, 4-Terpineol, dipentene/limonene, -Terpineol, linalyl acetate, linalool, -Terpinene and -Terpinene. The components are also mandated for inclusion in the oils. Four components in the oils were common in both lavender and tea tree and the remaining four were selective to each oil.
The researchers used in vitro models to apply the chemicals to human cancer cells to measure changes in estrogen receptor- and androgen receptor-target genes and transcriptional activity. Ramsey explained that the components in the oils possess EDCs that are estrogenic and antiandrogenic and contribute to prepubertal gynecomastia.
Certain chemical components of lavender and tea tree oils have been identified as EDcs and topical use in prepubescent boys may lead to the development of male prepubertal gynecomastia.
“We have determined that the EDCs — lavender and tea tree oil components — act like the natural hormone, meaning that they combined to the receptor and they can initiate these responses,” Ramsey said. “In a prepubescent boy, a lot of the time, the natural hormone is not present and should not be present during this time.
“Even more interesting is that the eight components that we chose for this study are in at least 62 of 93 other essential oils indicating that they contain EDCs as well. The bottom line is that the public should be aware of these implications and risks when deciding to use essential oils,” he said.
Ramsey called for further investigation of the link between essential oils and gynecomastia. – by Amber Cox
Ramsey JT, et al. OR22-6. Presented at: The Endocrine Society Annual Meeting; March 17-20, 2018; Chicago.
: Ramsey reports no relevant financial disclosures.