Oils in Soaps, Shampoo Linked to Gynecomastia in Boys
Lavender and/or tea tree oil may possess endocrine-disrupting properties
WEDNESDAY, Jan. 31 (HealthDay News) -- Topical use of products such as soaps or shampoo that contain lavender oil and/or tea tree oil may result in prepubertal gynecomastia in boys, researchers report in the Feb. 1 issue of the New England Journal of Medicine.
Derek V. Henley, Ph.D., of the National Institute of Environmental Health Sciences in Research Triangle Park, N.C., and colleagues report on three otherwise healthy prepubertal boys with gynecomastia and normal serum concentrations of endogenous steroids. The boys, aged 4 to 10, all had used lavender-scented soap and skin lotions, shampoo or styling products that contained tea tree oil and lavender oil.
The gynecomastia subsided several months after the boys stopped using the products. The researchers tested the oils on human cell lines and demonstrated that they had estrogenic and anti-androgenic activities. Taken together, the case studies and the laboratory study confirmed that the oils were the likely cause of the prepubertal gynecomastia.
"We suggest that the medical community should be aware of the possibility of endocrine disruption and should caution patients about repeated exposure to any products containing these oils," the study authors write.