Gone are the days of vacationing at the beach with a nose covered in a thick, white coat of old-fashioned sunblock. Manufactures have now developed “super sunscreens” that leave little residue, with SPFs reaching upwards to 100+ SPF. Widespread use of these new chemicals as sunscreens has sparked questions regarding accurate labeling of SPF, as well as sunscreen safety.

The current labeling of SPF, short for Skin Protecting Factor, can be misleading. SPF only refers to the amount of (ultraviolet) UVB rays that are blocked. UVA rays do not cause sunburn, but do penetrate the skin and contribute to skin cancer risk. A product with a SPF of 15 blocks about 94 percent of UVB rays, and an SPF 45 product blocks 98 percent of UVB rays. The benefit of the additional small percentage of UVB rays that are blocked with a SPF 100+ product may not be worth the cost or risk, because most of the chemicals used in these new and improved sunscreens have not undergone extensive safety studies.

The two most effective traditional sunscreen chemicals are titanium dioxide and zinc oxide. Both leave a white, chalky residue on the skin. Manufactures are now using nanotechnology to make these chemicals super-tiny, so that they will penetrate into the skin rather than creating a barrier on top of the skin.

This may be very effective at preventing sunburn, but if the nanoparticle oxides are small enough to pass through the skin into the body, that creates concern about systemic exposure. They would even be small enough to enter into cells and cause DNA damage. The FDA did not require additional safety testing of the nanoparticles, because they are the same chemicals. However, the little information we do have clearly shows a need for more consideration before allowing widespread use in the general population.

A much safer alternative is a product like All Natural Sea Buckthorn Sunscreen SPF 15. The best way to insure protection is to apply sunscreen 15 to 30 minutes before going out, and then reapply after 20 to 30 minutes of sun exposure. Reapply again after perspiring, swimming or towel drying. The negative long-term effects of solar radiation exposure may be subtle, but they are real.

Rebeca Gracia, PharmD, is a board certified toxicologist and director of Whole Life Pharmacy, 1130 Dragon St., Dallas. Contact her at 214-741-3332 or Whole-Life-Pharmacy.com.