Mold on silicone grout in the bathroom is not just an aesthetic problem. It is a microbiological phenomenon that can also affect the air quality in the room over time, especially if the bathroom is not properly ventilated. It most often appears in the form of black stains on the joints between the bathtub, shower and wall, where moisture often accumulates. The cause of its formation is a combination of a warm and humid environment, insufficient air circulation and the presence of organic residues (cosmetics, skin cells, etc.), which serve as food for mold.