Group 1 - High temperatures in North China and Huanghuai regions are expected to rise, with local temperatures reaching up to 39°C, leading to potential hazards in closed car environments where temperatures can soar to 60-70°C [1] - A recent incident in Pinghu, Zhejiang, involved a car fire caused by a faulty USB data cable overheating and igniting the seat [2] - Another fire incident in Beijing was attributed to a power bank left in a car, which experienced "thermal runaway" due to high temperatures [4] Group 2 - Fire departments warn against using cars as storage spaces during summer, as items like bottled water, old glasses, and aerosol products can ignite under high temperatures [5] - A simulation experiment demonstrated that common car items, such as air fresheners, can become fire hazards when exposed to flames in high-temperature conditions [10] - Bottled water can act as a lens, focusing sunlight and potentially igniting nearby flammable items, with temperatures reaching up to 120°C [11][13] Group 3 - Experts caution against consuming beverages left in hot cars, as bacteria can proliferate in opened drinks after prolonged exposure to high temperatures [14] - Laboratory tests showed that unopened bottled water and certain drinks did not contain bacteria, while opened drinks tested positive for bacterial growth after being left in high temperatures for 72 hours [17] - The risk of bacterial contamination increases significantly for opened drinks, especially those containing proteins, which can promote faster spoilage [19]