Samm UR, Sunblock hazardous to sea life?

The article I found for this week deals with sunblock and it's affects on ocean life. The article states that titanium dioxide and zinc oxide nanoparticles (which are common ingredients in sunscreen) can interact with ultraviolet light to form hydrogen peroxide, which could be toxic to micro algae, like phytoplankton. These micro algae will go on to feed other fish and whales.
The first thing I did after reading this article was to run straight to my sunscreen to look at the ingredients! I didn't necessarily find the two chemicals the article stated, but they could be under a different name. Although, simply trying to google it gave me a couple of websites that talked about how titanium dioxide and zinc oxide were used more as sunscreens because they are more likely to "scatter" the UV Rays  more than other man-made, chemical ingredients.
It's intriguing (and alarming) to find something that we use often (like sunscreen) might actually be harming the environment and the creatures that live in it, especially when we talk about how much better it is for US. It definitely makes you think about what you're really buying and using, knowing how it will not only affect you, but everything around you.
In the article, the two researchers went to Majorica Island's Palmira beach (in Spain) to test the seawater for spikes in hydrogen peroxide levels. I would be interested to see what kind of hydrogen peroxide levels are found in our beaches, and if it's affecting phytoplankton.