Dirty fingernails after drinking

I can’t be the only one. Most times after a heavy night I wake up in the morning with dirty fingernails, like dirt and grime under them. The thing is I never do anything during the night that could cause all this junk buildup under my nails. But alas, around 7 times out of 10 i wake up in the morning after a night of heavy drinking with basically black fingernails. Has anyone else had similar experiences or knows the reasoning behind this?