health problems
Endocrine disruption: Homosalate can affect the body's hormone system, especially the estrogen system. [8][9] In human breast cancer cells, which grow and reproduce due to the effects of estrogen, exposure to homosalate resulted in a 3.5-fold increase in cell growth and reproduction. [10]
Several studies have established that the androgen and progesterone systems are affected by homosalate exposure. The androgen and progesterone hormone systems are also affected by homosalate. [11][12][13][14][15][16] Although these findings have only been observed in cell culture, caution should be exercised given the role of these hormones in the regulation of reproductive organ development.

The endocrine disrupting effects of homosalate are of particular concern because homosalate and other cosmetic UV filters have been found in human breast milk samples [17], and the estrogenic activity of homosalate has been observed in human placental tissue. [18] Pregnancy and infancy are developmentally fragile times where exposure to hormone-disrupting compounds may lead to adverse health effects.

Contamination of breast milk can be common. In a study of 54 mother-child pairs, 85.2% of breast milk samples contained UV filters. [19] Maternal use of products containing UV filters during pregnancy and/or breastfeeding was significantly associated with the presence of these compounds in milk.

Skin Absorption: Homosalate is absorbed into the outer layers of the skin. [20][21][22] Commercially available sunscreens containing homosalate have been shown to increase the amount of pesticides we absorb through the skin. Increased absorption of the herbicide 2,4-D was found in mice exposed to sunscreen containing homosalate and the powerful insect repellent DEET.