Issues to consider:
- Will the chemical penetrate skin and reach living tissues?
- Will it disrupt the hormone system?
- Can it affect the reproductive and thyroid systems and, in the case of fetal or childhood exposure, permanently alter reproductive development or behavior?
- Can it cause a skin allergy?
- What if it is inhaled?
- Other toxicity concerns?
If you want to error on the side of it is safe until considered safe by all, then try to avoid the ingredients below when buying sunscreen.
- Retinyl Palmitate - not required; it just is thought to reduce signs of aging and has been linked to skin cancer.
- Oxybenzone - a common UV filter that has been shown to interact with hormones when fed to animals in large amounts (much greater than sun screen contains). Avoid this because it readily pentrates the skin.
- Octinoxate (Octylmethoxycinnamate) - Hormone-like activity; reproductive system, thyroid and behavioral alterations in animal studies.
- Nano-particles - Zinc oxide and titanium dioxide are mineral based sunscreens that provide broad-spectrum protection. If the particles have been shrunk to micro or nano-particles so that they no longer leave a white color then they may not be safe anymore. They are thought to possibly enter the body an cause cancer, but more information is needed. To keep it safe, it is best to buy sunscreen that says "non-nano-particles". If it stays on as white then it should be safer as it is not likely using nano-particles. Labelling is not required.
- Titanium Dioxide - concerns if inhaled, so buy choose topical application, not a spray.
- Zinc Oxide - concerns if inhaled, so buy choose topical application, not a spray. Skin penetration, but in very small number amount (.01%).
- SPF 15 - It doesn't provide protection against skin cancer, but does from sunburn. It is recommended to use SPF 30. SPF 50 may be used as well, but some believe it is not necessary. Also, beware the higher the SPF may also mean higher concentration of harmful chemicals.
- Homosalate - Disrupts estrogen, androgen and progesterone
- 4-methylbenzidyl camphor - used in Europe and under petition for use in the U.S. is a hormone disruptor.
- methylisothiazolinone, or MI - a preservative and inactive ingredient. It is a major allergen.
- Avobenzone -best chemical filter for UVA. Relatively high rates of allergies
- Mexoryl SX - skin penetration. Currently not fda approved
- Octisalate - skin penetration
- Octocrylene - skin penetration
"Zinc oxide is EWG’s first choice for sun protection. It is stable in sunlight and can provide greater protection from UVA rays than titanium oxide or any other sunscreen chemical approved in the U.S."
To find the product you want use the advance search on http://www.ewg.org. They have rated by ingredients tons of sunscreens. I found this site so valuable when deciding on sunscreens.
I found Badger products such as Badger Sunscreen Cream, Unscented, SPF 30 to be a good product that can be found on Amazon for the US and UK. There is also a sport version called Badger Sport Sunscreen Cream, Unscented, SPF 35. It can be found on Amazon for UK and US.
References:
Sunscreen Safety: What to Know
The Trouble With Sunscreen Chemicals
