The new car smell is actually is a complex mixture of volatile organic compounds (VOCs), primarily alkanes and substituted benzenes along with a few aldehydes and ketones.

Individual components of new car smell probably aren’t harmful at the concentrations found in cars, but the cumulative effects of long-term exposure to the total mix of VOCs could pose health problems. Fortunately, high concentrations of these compounds quickly dissipate just a few months after manufacture. And although VOC concentrations can reach unhealthy levels in a closed vehicle on a warm day, the air-exchange rate in a car is high when someone opens a door, rolls down a window, or turns on the air conditioner.

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