New hose, contamination?

admin

So, I just bought some hoses (new) for a small oxy/fuel setup I'm putting together.  When I looked at the hose ends, I saw a little brown spot on the end of the cone inside one fitting.  Wiping it, it looked like it might be a tiny bit of grease (not 100% sure).  I know that there are some issues with oil and oxygen... but I'm not sure how paranoid I should be.  Is it safe to just wipe it?  Should I use rubbing alcohol or acetone?  Do I need to worry small quantities of that getting on the hose?Of possible note: I'm not using an oxygen tank, I'm using an oxygen concentrator, so it'll be a pretty low pressure system.Thanks voices of experience!