A recent Aston University study uncovers alarming levels of bacteria in car interiors—surpassing even toilet hygiene standards.
Published on January 31, 2022, by researchers at Aston University in Birmingham, UK, this study highlights greater bacterial contamination in car passenger compartments than in bathrooms. While counterintuitive, it's understandable given how infrequently we deep-clean our vehicles compared to restrooms.
Scientists swabbed samples from diverse vehicles with varying histories and environments. Key findings included harmful bacteria such as Escherichia coli, Staphylococcus aureus, and Pseudomonas.
The trunk emerged as the most contaminated area, averaging 1,425 bacteria—likely due to storing groceries and dirty items. Surprisingly, the steering wheel ranked lowest at 146 bacteria, thanks to widespread hand sanitizer use over recent years. Other areas trailed: driver's seat (649), gear knob (407), rear seat (323), and dashboard (317).
Researchers attribute bacterial buildup to prolonged vehicle use and ownership changes. They recommend thorough interior cleaning at least monthly, prioritizing the trunk, seats, and carpets—ideally with a steam cleaner for deep sanitation.
These bacteria pose real health risks: Escherichia coli can trigger gastroenteritis, urinary tract infections, or meningitis; Staphylococcus aureus may cause food poisoning or skin infections; and Pseudomonas species can lead to wound infections, sepsis, or other serious conditions.
