1. Which statement does NOT accurately explain the difference between chemical and physical sun blocks?
A. All physical sunscreens block out UVA and UVB rays, while only some chemical sunscreens offer UVA protection.
B. Chemical sunscreens take 30 minutes to become effective, while physical sunscreens are effective immediately.
C. Chemical sun blocks are absorbed into the skin, while physical sun blocks stay on the skin's surface.
D. Physical sunscreens are invisible on the skin, while chemical sun blocks may leave a white appearance.
2. What percent of sunscreens tested contained hazardous chemicals or didn't provide full protection from sun damage according to a 2009 study by the Environmental Working Group (EWG)?
3. All sunscreens are required to contain protection against harmful UVA rays.
4. Which sunscreen received the highest ranking for safety and protection by the EWG?
A. Badger SPF 30
B. Vanicream SPF 60
C. Mustela SPF 50
D. L'Uvalla SPF 20
5. SPF 30 is twice as effective at blocking harmful UVB rays as SPF 15.
1. Answer D.
Physical sunscreens containing titanium or zinc oxide offer many benefits like full spectrum protection and immediate coverage. Because they remain on the surface of the skin, physical sunscreens may leave a slight white residue on the skin. This means you are covered!
2. Answer C.
Sixty percent of the over 900 products tested by the EWG raised concerns based on their lack of protection or chemical components. This non-profit group recommends using a solar block with SPF 30 or higher that includes UVA protection, while avoiding fragrances and oxybenzone.
3. B - False.
The SPF (sun protection factor) rating only represents a sunscreen's effectiveness at preventing sunburns caused by UVB rays. UVA rays also contribute to cellular damage that can cause skin cancer; however, the FDA has not developed a system for rating a product's effectiveness for UVA protection.
4. Answer A.
Badger SPF 30 has again achieved the highest ranking for sunscreens by the EWG. This best-selling physical sun block contains micronized zinc oxide to provide full spectrum protection. The other products mentioned were among those recommended by the EWG study, and are also available at Pharmaca.
5. B - False.
A product with an SPF of 15 screens about 94% of harmful UVB rays, while a product with an SPF of 30 screens about 97%. Higher SPF products block only about 1-2% more UVB rays, and require additional ingredients that can be absorbed into the body. Most experts recommend using SPF 30 and reapplying every 2 hours you are exposed to sun light.
Thanks for taking our quiz! If you have other questions about sun block or skin care, ask one of Pharmaca's licensed estheticians.