Is Homosalate Safe?

Physical sunscreens typically use 1 or sometimes 2 active ingredients.

Chemical sunscreens need to use 3-4 or even more active chemical ingredients to either a) cover the entire UV spectrum and/or b) compensate for ingredient deterioration.

If you’re researching if homosalate is safe, you’ve come to the right place. In this post, we’ll answer:

What is homosalate?
Is homosalate safe for humans?
Is homosalate reef safe?

Let’s begin.

What is Homosalate?

Homosalate is an oil-soluble chemical sunscreen ingredient used to absorb UVB rays (the rays produce sunburns in the upper layer of skin). Ironically it is a weak UV filter (at 10% concentration it is an SPF 4) and is not photostable (meaning it breaks down in sunshine). It is a derivative of salicylic acid. Salicylic acid is used to remove the outer layer of skin and treat warts and acne.

Because homosalate only covers the UVB spectrum, it is usually combined with avobenzone (a chemical UVA filter) to get broad-spectrum coverage.

As most ingredients in chemical sunscreens homosalate works by absorbing into skin — it does not sit on top of skin like zinc oxide.

On labels, homosalate might also be listed as Homomenthyl salicylate, or HMS.

EWG Rating: 2-4 (1 best, 10 worst)

Is Homosalate Safe for Humans?

Research indicates it is a weak hormone disruptor, and sunlight degrades the chemical into potentially harmful byproducts.

This study also links homosalate to hormone disruption and it may also enhance the absorption of pesticides, (if you’re using a sunscreen + bug spray product or do a lot of gardening with pesticides). Once through your skin, these chemicals usually enter your bloodstream.

Some lab studies (in-vitro) have shown homosalate might have some estrogenic activity as well.

In 2019, FDA published a study showing oxybenzone, octinoxate, octisalate, octocrylene, homosalate and avobenzone are all absorbed into the body after a single use. The FDA also found the sunscreen ingredients could be detected on the skin and in blood weeks after application ended.

All Waxhead sunscreens and skincare products are homosalate-free.

Studies have found human breast cancer cells, when exposed to homosalate, grew and multiplied 3.5 times more than normal. The estrogenic activity of the chemical has also been observed in human placental tissues, raising concerns about pregnant women who may be exposed to the chemical.

Although numerous studies exist on the toxicity of homosalate and the effects on the human body, homosalate is approved worldwide. The U.S. FDA approves usage levels up to 15%.

We recommend children, adults and pregnant mothers avoid this chemical in sunscreens and any skincare product.

Is Homosalate Reef Safe?

Homosalate has become ever present in the environment, and it doesn’t break down easily. UV filters such as homosalate enter coastal waters either directly by washing off swimmers and/or indirectly from wastewater treatment plants. Many of these chemicals have been found in marine life including fish and corals as well as in sea bed floor sediment.

Oxybenzone’s effect on coral is widely studied, but unfortunately, there is insufficient data to determine the safety of homosalate on coral reef. But just because there isn’t a ton of science proving homosalate is bad for reef environments, doesn’t mean it is safe to use. Further research is needed to better understand which ingredients are safe and which pose a threat to marine ecosystems and in the meantime, we recommend avoiding homosalate.

The term “reef safe” is not regulated by the FDA, and its growing use is largely due to the sunscreen industry’s desire to attract eco-aware consumers.

NEXT STEPS

1. Know your ingredients — Flip over your sunscreen and read the ingredients. We want everyone to know what good ingredients are, regardless of whether they use our products or not. Your health is worth it.

2. Buy safe sunscreen — Waxhead is dedicated to using only the healthiest, safest, most effective ingredients in our sunscreens. Shop Safe Sunscreen here.

3. Teach a friend — If you know someone who might still be buying sunscreen with questionable ingredients, please share this post with him/her.