San Francisco Department of the Environment

How can I choose the safest and most effective sunscreen?

Consider these guidelines to make sure that your sunscreen not only protects your skin, but also contains ingredients that are safer for your body. 

Safer Sunscreen (Sunblock) Guidelines

Reduce the amount of sunscreen you need in the first place

Stay in the shade and wear hats and clothes like long sleeves that cover your skin. Long sleeves and pants aren't just for cold days! Consider wearing loose cotton or linen, which can keep you cool while protecting you from the sun. 

Look for these qualities to find the safest and most effective sunscreen

  • Check the label for products that are lotion-based (instead of spray), water-resistant, and are broad-spectrum (protect from both UVA and UVB rays).
  • Look for products that are at least SPF 15 but no higher than SPF 50. Sunscreen that is higher than SPF 50 is not proven to be more effective than lower SPF sunscreen, and an increase in SPF may increase exposure to chemicals.
  • Look for products that do not come in aerosol containers, since you can potentially inhale the product chemicals when sprayed.
  • Look for mineral based sunscreens such as zinc oxide and titanium dioxide. These block UV rays better than chemical sunscreens, and have less adverse health and environmental effects. 

Check the ingredient label and try to avoid products that:

  • contain Oxybenzone or Octinoxate, which are hormone disrupting chemicals and are known to cause damage to coral reefs
  • contain Vitamin A  (also known as retinyl palmitate or retinol) which may speed the development of skin tumors and lesions
  • contain methylparaben or ethylparaben (also known as parabens) or fragrance. Parabens are a class of chemicals that may have estrogenic activity (can affect your hormones) and may also react with UVB rays, resulting in DNA damage
     

Follow the Precautionary Principle and check for micronized particles or nano-particles

While studies are still being conducted to assess the safety of nano-particles, the precautionary principle would tell us to avoid products with nano-particles. Many sunscreens already advertise the use of non-nano particles.