CS>odd situation

[PT Ferrance]

Hi, I was wondering if someone can help?  About 6 weeks ago I made some CS to 
take with me on a trip.  I made it with a silver puppy and it was perfectly 
clear and seemed potent.  I put it in a Rubbermaid plastic water container and 
carried it with me.  After about 3 weeks on the road it turned a brownish 
color.  Can anyone tell me why this happened and if it is still good to use?
Thanks. PT