He's taking an interest in food once again and acts just about back to normal. 
lvstorts said:I took in a rescue covered in grey paint because the kids who had her thought she needed a 'helmet.' I didn't use anything but good old fashioned nature. After a few weeks of summer sun to crack the paint and the scraping of the shell under bushes and logs, I was able to chip away at it. Took all summer but she's not worse for the wear.
Have the owner give him a lot of soaks to get the nail polish remover out of his system. I'm sure the fumes are in his lungs and making him not feel so good.