Click here for full article.

Excerpt from article...

"Sunlight also boosted the toxic effects, another study found. PAHs enhance the ability of tissues to absorb harmful ultraviolet radiation, explained Aaron Roberts of the University of North Texas in Denton. "We like to think of PAHs as being the anti-sunblock," he said.

To probe this phototoxicity in egg fertilization, Roberts' group collected newly spawned eggs and sperm from clean, lab-reared sea animals and then mixed the cells into oiled seawater. For the most sensitive species, blue crabs and mahi mahi, it took just 2 to 6 micrograms of PAHs per liter of water to diminish the eggs' normal rate of fertilization -- at least when solar UV radiation was present. Even after blocking 90 percent of the UV rays, enough still got through to diminish fertilization success beyond the harm caused by oil alone, Roberts said.

In these species, "Photo-enhanced toxicity can account for up to a 20-fold higher sensitivity," observed coauthor Martin Grosell of the University of Miami in Florida."