This is a can of black paint. It's got lead in it, though, so it can't be sold in normal stores because of safety regulations. Stupid kids and their wall candy.
Lead-based paints, despite improved performance, were discovered to be extremely toxic, and one myth is that the most common cause of poisoning was eating leaded paint chips. The most common way children were exposed to lead was probably from ingestion of lead dust dislodged from deteriorated paint or during remodeling.
The correlation between black paint and red doors refers to the song Paint It, Black by The Rolling Stones: "I see a red door and I want it painted black" and "I see my red door I must have it painted black."