France heatwave warns of exploding aerosols and ruined medication in parked cars

During the historic French heatwave, interior car temperatures can exceed 80 °C. This extreme heat creates pressure in aerosol cans, increasing the risk of explosions and fires. Lithium‑ion batteries in smartphones, laptops and tablets may overheat, potentially igniting or causing thermal runaway.

Medications stored in hot cars can lose potency, especially liquids, insulins and injectables, and should not be used if they change colour, smell or texture. Credit‑card chips and magnetic strips can become distorted, and plastic water bottles may leach chemicals, affecting taste and safety. Other items such as disposable lighters, wet towels and sunscreen can also degrade or become hazardous.

Authorities advise keeping such objects out of direct sunlight, storing them in shade or cooler environments, and checking any medication or electronic device for signs of damage before use.