http://almashriq.hiof.no/lebanon/600/610/614/solar-water/unesco/ The authors give an excellent summary of the practical aspects of solar radiation and disinfection of drinking water.
http://www.sodis.ch/index_EN
Discussion of solar disinfection of water SODIS. Information on effects of UVA from sunlight.
http://publib.upol.cz/~obd/fulltext/Biomed/2006/1/25.pdf Discussion of UV effects on the skin. Much is applicable to the eye
<http://physrev.physiology.org/content/86/2/583.full> Ryter, S. W., Alam, J., & Choi, A. M. K. (2006). Heme oxygenase-1/carbon monoxide: From basic science to therapeutic applications. Physiological Reviews, 86(2), 583. doi:10.1152/physrev.00011.2005 Discussion of the stress protein heme oxygenase. I suspect activation of this enzyme produces the high levels of iron seen in liver and serum of some animals.