Every consumer, particularly expectant or nursing mothers, parents of young or adolescent children, and couples trying to conceive- deserve to make an informed choice:
- Either use sunscreens with soluble filters of small molecular weight that give incomplete protection and pass into blood, tissues and brain, and are implicated as hormone disruptors and carcinogens, with adverse effects on lower species and the environment/
- Or to use insoluble particle based UV filters with large molecular weight or particle size that give better protection against skin cancer and photoaging, and remain on the skin without any risk to human health or the environment.
- Absolutely avoid– avobenzone, oxybenzone, homosalate, octisalate, octocrylene, Mexoryl XL™, Eusolex™ (4-methylbenzilidene camphor), octinoxate (un-encapsulated)- some are known or suspected hormone disruptors, photoallergens, and carcinogens. The fact that they all attain levels in your blood is reason enough to avoid them even without considering risks, particularly for expectant or nursing mothers, young or adolescent children, and couples trying to conceive.
- Select – large molecular size insoluble particles or engineered filters: Zinc oxide, titanium dioxide, encapsulated octinoxate, Mexoryl SX™, Tinosorb S™, Tinosorb M™, Parsol SLX™, iscotrizinol, octyl triazone, and bisdisulizole disodium. They have no entry into blood and none are hormone disruptors or photoallergens. They give balanced protection without any risks to human health or the environment. Only the first four are available in N. America.
- Select a particle based product with adequate concentrations to provide an accurate SPF and enough UVA protection. A SPF of 30 and a UVA-PF of at least 10 is attainable with zinc oxide alone 22-25%,zinc oxide 15% plus 5% titanium dioxide or encapsulated octinoxate. I like Mexoryl SX ™ is but it is usually combined with undesirable soluble filters. Combinations of zinc oxide and titanium dioxide in adequate concentrations are hard to find. Some products that fly off the shelves in health food stores have inadequate concentrations of these filters- e.g. 1.2% and 3.8% respectively. This cannot have the SPF 30 claimed on the label and likely contains boosters (anti-redness agents) that diminish your erythema reaction from sunburn without actually reducing the UVB radiation passing through the sunscreen to your skin. The filters are safe but at that level cannot provide adequate UVA protection- likely has a UVA-PF < 5 and would be a FAIL in the EU and cannot deliver adequate photoprotection.
- Higher UVA-PF values are possible with the use of either more zinc oxide up to 25%, or the addition of innovative filters like Tinosorb S™, Tinosorb M™ – approved everywhere in the world – except N. America. Most sunscreens here have UVA-PF values of 3-8, despite being labelled as “Broad Spectrum” under our rules that do not actually require this measurement, and rely on an indirect estimate. Most still fail to reach EU standards. The ideal sunscreen would combine 3 or 4 particle filters – encapsulated octinoxate, zinc oxide, titanium dioxide, Tinosorb S™ (bemotrizinol), or Tinosorb M ™ (biscotrizole). Only the first 3 are available to us in ideal combinations. These combinations in optimal concentrations can achieve UVA protection values > 30, and achieve 3-5 X more protection in the UVA1 range than our typical UVB-biased N. American sunscreens.
- For daily or recreational purposes, use SPF 30 – but if you are extremely fair, if you have a condition with extreme sensitivity to sunlight like lupus, or if you have an outdoor occupation, use a SPF 50. Bear in mind that the true SPF may only be 10 and adjust your behaviour accordingly – calculate your safe exposure time from the label SPF and divide by 5. Particle sunscreens appear to come closer to their label values in sunlight. Use the other elements of a photoprotection strategy – avoid sun exposure, wear UV protective clothing, wear head gear and UV protective sunglasses to the extent you can, and use a sunscreen with UVA filters like zinc oxide in adequate concentrations.