A fine layer of black dust, too small to see with the naked eye, accumulates on asphalt roads after vehicles brake. This dust is created when brake pads rub against brake discs, and it contains heavy metals like copper, antimony, zinc, iron, and occasionally lead. Over time, this dust builds up on roads and in gutters. When autumn rain falls, it washes the dust into storm drains, which carry it into rivers and groundwater. This process can introduce harmful substances into water systems, potentially harming aquatic plants and animals. While exhaust emissions from vehicles have long been monitored for their environmental impact, braking dust has received much less attention. This form of pollution affects all types of vehicles, including electric cars, which produce no tailpipe emissions but still generate braking dust. Rainwater, often viewed as a natural cleanser, actually plays a role in moving this pollution from roads into rivers, where the heavy metals can settle into sediments and disrupt ecosystems. Researchers and manufacturers are exploring solutions to reduce the environmental impact of braking dust. This includes developing brake pads that release fewer heavy metals and designing systems to capture particles at the braking point. Cities are also looking at ways to manage stormwater more effectively, such as increasing green spaces, building retention basins to hold runoff, and planning urban areas to reduce the amount of hard, impermeable surfaces that contribute to runoff. Individual drivers can also help by practicing smooth driving, anticipating the need to brake, and maintaining their vehicles' braking systems. Reducing the number of short trips can also lower the overall amount of braking needed. If these measures are widely adopted, they could significantly reduce the environmental impact of braking dust and help protect water systems and the ecosystems that depend on them.