What does 420 mean dirty?

Excuse me, could you please clarify what you mean by "420 mean dirty"? The number 420 has various connotations, but typically in cryptocurrency and finance circles, it's not directly associated with anything "dirty" or negative. Could you be referring to a slang term or phrase that has somehow intertwined with the number 420? If so, it might be helpful to provide some context or explain the cultural background to help me understand your question better.