I don't want to pick on Coola Face SPF30 unfairly. What caught my eye is that it contains octocrylene, octinoxate, oxybenzone, octisalate. These are chemical sunscreens that are fairly common, but always in the back of mind I am thinking: are they safe, didn't I read somewhere... even post something? Keeping it all straight is made even harder by the fact they have such interchangeable names. So finding four oxy-whatsits in one go gives me a good excuse to summarize what they do and whether they are safe.

Octocrylene (Maximum recommended by FDA: 3%)

Octocylene absorbs UVB and short-wave UVA. It's chemical name is 2-ethylhexyl 2-cyano-3, 3- diphenylacrylate.

Safety measures/side effects

Although there is evidence that octocrylene is responsible for reproductive toxicity, the trials used doses far higher than would be used in cosmetics. That doesn't mean to say that they aren't dangers, only that we don't really know.

Octocrylene can penetrate into the skin and act as a photosensitizer, resulting in an increased production of free radicals. Free radicals can induce indirect DNA damage and potentially contribute to the increased incidence of malignant melanoma in sunscreen-users compared to non-users. Although this might theoretically apply to other sunscreens, the study that made this conclusion refers only to octocrylene.

Another reason to reconsider octocrylene, is that it has been found in fish. According to a Swiss study, it is quick to biodegrade and then bioaccumulate. The few fish we have left on the planet should probably go as chemical free as possible.

Oxybenzone (Maximum recommended by the FDA: 6%)

Oxybenzone, a derivative of benzophenone, is often used in conjuction with other sunscreens because it helps stabilize them and also because its sun protection powers are too weak to be used alone.

Safety measures/side effects

As a photocarcinogen, it’s demonstrated an increase in the production of harmful free radicals and an ability to attack DNA cells; for this reason, it is believed to be a contributing factor in the recent rise of melanoma cases with sunscreen users. Some studies have shown it to behave similarly to the hormone estrogen, suggesting that it may cause breast cancer. It has also been linked to contact eczema.

For many years, the dangers were ignored on the assumption that oxybenzone didn't get absorbed by the skin. A team of researchers in Australia, led by Cameron Hayden, demonstrated otherwise using commercially available sunscreen with a 6% concentration  of oxybenzone. Haydon's conclusion: the use of oxybenzone is inadvisable for large surface area application for extended and repeated periods.

Urine tests show that it sticks around. In 2008, the US Centers for Disease Control & Prevention conducted a similar experiment on a national scale, and found the chemical compound to be present in 96.8% of the human urine samples surveyed. As a result, it is recommended that parents keep their small children from using products containing the ingredient oxybenzone.

On the other hand, a California study on fish, concluded that it did not have any adverse effects on reproduction.

Octisalate, octyl salicylate, or 2-ethylhexyl salicylate (Maximum recommended by FDA: 5%)

Octisalate or octyl salicylate is used to augment the UV-B protection in a sunscreen. Salicylates are weak UV-B absorbers, and they are generally used in combination with other UV filters because they are insufficient on their own. It typically undergoes some degradation when exposed to sunlight.

Safety Measures/Side Effects:

Octisalate's safety record seems to be fairly good although it has been linked to contact dermititus.


Octinoxate or octyl methoxycinnamate (Maximum recommended by FDA: 7.5%)


Octinoxate is the most widely used UVB blocking agent in the skin care industry. It does not filter UVA rays. Studies have also shown that Octinoxate can protect the skin against not only sunburn but also UV light-induced DNA alterations (Source).

However, it isn't very stable. When octinoxate is exposed to sunlight, it is converted into a less UV absorbent form (from E-octyl-p-methoxycinnamate into a Z-octyl-p-methoxycinnamate). Given that its job is to be exposed to sunlight, this seems to me to be a somewhat fundamental limitation. It is why you will usually find octinoxate combined with another sunscreen. Beware, though, that octinoxate combined with avobenzone degrades even faster (source).

Safety Measures/Side Effects:

According to the EWG, Octinoxate is a moderate hazard, primarily because it can lead to developmental and reproductive toxicity through enhanced skin absorption. It’s a penetration enhancer and is easily absorbed into the skin. It can produce estrogen-like effects and should not be used by pregnant women and children. However, the research is contradictory as to what concentrations are toxic. One Norwegian study in 2000 declared toxicity on mice at levels much lower that that used in sunscreen. Studies of percutaneous absorption indicate that 1 to 2% of the applied material may be absorbed through the skin. Most of the octyl methoxycinnamate appears to be trapped in the stratus corneum  in adults. However, concerns have been expressed about the use of this sunscreen ingredient in children where the stratus corneum is less likely to be protective.

Other studies, were the result of concentrations higher than any formulas in skin care products. Bottom line: More research is needed. Given that it isn't even very stable in sunlight, it's probably not worth the risk.

Editor’s note: Also read Marta’s Five Best mineral sunscreens. 

See all our FIVE BEST recommendations including Five Best for sagging skin, Five Best with vitamin C and Five Best eye creams