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This could be conjunctivitis, or a viral infection, if the eye is running (having discharge) clean the area with warm washcloth to get the matting out. If the eye is still discharging and matting you may need antibiotic drops.
There is also something called pannus which actually covers the eye with a gray pink film. this can diminish the dog's vision. I am going to direct you to a site on this. Take a look at the picture in the upper left of the page.
Cataracts will also cause a bluish hue that may look white in certain light. This n also cause tearing. http://www.petplace.com/dogs/cataracts-in-dogs/page1.aspx