Oops, it doesn't look like 'Filth day' is a national day..

Other days

ruby

Ruby Day
nae nae

Nae Nae Day
first love

First Love Day
singles

Singles Day
gum

Gum Day
polyamory

Polyamory Day
law

Law Day
raise awerness of zeus

Raise Awerness Of Zeus Day
nail polish

Nail Polish Day
cuddle up

Cuddle Up Day