Time to get the jump on summer with a good sunblock (and, we hope, some sun). By good we mean safe:  for you and the water you dip in; we recommend products that use only the natural minerals titanium dioxide and/or zinc oxide (emblem of the lifeguard nose) as active ingredients. The other kind of active ingredients, synthetic chemicals, are giving rise to some serious concerns.

In March, the U.S. Centers for Disease control announced that, based on their ongoing "body burden" studies of a representative sample of our population, 97 percent of Americans carry oxybenzone, a common sunscreen ingredient, in our bodies. The skin is a highly absorptive organ and oxybenzone, also known as benzophenone, is a "penetration enhancer," so sunscreen is a pretty likely suspect. According to Environmental Working Group (EWG),  oxybenzone is associatd with allergic reactions and may be a human hormone disruptor. What isn't absorbed by your skin can hurt aquatic ecosystems when you swim or snorkel: A study published this year found that oxybenzone can cause viral infections in coral reefs, and feminization of male fish.

Happily, there are many effective (SPF 15 and above) mineral sunblocks that are free of this and other troublesome chemicals. Make sure that any sun protection you buy is full-spectrum, keeping out both UVA and UVB rays. Below are some mineral blocks that fit the bill, including several that we have tested and recommended.

Alba Botanica Fragrance-Free Mineral Sunscreen

All Terrain TerraSpoprt/AquaSport


Burt's Bees Chemical-Free

California Baby No Fragrance

Dr. Hauschka

Jason Sunbrellas Chemical Free

Kiss My Face Sunspray  

Korres Watermelon Sunscreen Face Cream  

Nature's Gate Kid's Block Giggleberry

Origins Sunshine State 

Go chemical-free, and your summer will go swimmingly. Plus the fish would thank you if they knew.

This article originally appeared in Plenty in May 2008. The story was moved to MNN.com.

Copyright Environ Press 2008