If the weather is mild, leaving water in the car is not an issue. But when your vehicle is parked under direct sunlight at noon, it’s a different story. That seemingly harmless bottle of water could literally turn your car into a “fire car.”

The reason is that water bottles, usually spherical in shape and made of transparent plastic, can act like magnifying lenses. When filled with water, they are capable of focusing sunlight into a single point. At midday, the temperature inside a car can reach nearly 60°C. With sunlight passing through the bottle and converging on a spot, the heat can rise even higher, creating a fire hazard.

Many people admit that leaving a bottle of water on the seat is something they often do, without ever imagining the serious consequences. Moreover, some car experts point out another risk: bottles placed on the passenger seat can roll off and get stuck under the brake or accelerator pedals. In emergencies where the driver needs to brake suddenly, a bottle lodged under the brake pedal could be extremely dangerous.