Why you shouldn’t leave bottled water in a hot car

Key Points:

• Single-use plastic water bottles made from PET can leach chemicals such as phthalates and BPAs into water when exposed to heat, which are endocrine disruptors linked to health issues including infertility and cancer, although current FDA guidelines consider their levels safe.
• Heated plastic bottles can release microplastics into the water, and emerging research suggests microplastics may cause oxidative and DNA damage, reproductive harm, and metabolic disorders, though human health effects remain not fully understood.
• Warm environments promote rapid bacterial growth inside water bottles, potentially leading to illness if contaminated water is consumed.
• Reusable insulated bottles made from food-grade stainless steel or glass are safer alternatives, avoiding many risks posed by plastic bottles, while harder reusable plastics like Nalgene are preferable over single-use plastics but still require care.
• Regular cleaning of all reusable bottles is essential to prevent bacterial and mold buildup, ensuring safer drinking water.