Qs on Eye Spot, Carefresh dust, and Mite Itching?

Background: I just returned from an extended vacation last night, and I checked on my piggies first thing after work today. While I was away, a naive but kind-hearted friend took care of them- a friend who has watched over them several times before, but still makes minor pig-care mistakes. Nevertheless, my piggies are nonetheworse for wear, and they seem happy. I changed all of the minor mistakes she made (including too many carrots, left laying around... sigh), and cleaned out their bedding. While handling them, however, I noticed something different about my older pig (around 4 years, but has history of being ill fed and ill kept, so I consider him getting older).

1. The older pig's right eye has a small white clearish dot on it, almost as if he has something very small stuck on his eye, but there's nothing there. It looks almost as if it's a trick of the light, but his other eye looks perfectly normal. Does this sound like a cataract, if pigs can have them? That was my first thought, given his age. I only noticed this today, once I came home- his eyes were fine before I left.

2. Also, I recently switched from Carefresh Colors to normal Carefresh right before I left, because of the price. Could this be leaving lots of tiny white fuzz over my entirely black older pig? My first instinct was lice, but it doesn't move, and he and his cagemate were treated with Advantage about a month ago. Seeing no other reasonable option, I'm thinking it might be dust. Should I change beddings, in case? It doesn't look very pleasant for the poor pig.

3. On a side note, unrelated to my piggies, I once heard that a clear sign your pig has mites is if your hands and arms itch after handling them. Is that true? Because I was already here, I thought I'd ask the experts.