The Chemistry Behind That New Car Smell

The interior of a new car has always ranked high in the pantheon of aromas, taking its rightful place alongside the smell of fresh-cut grass and bread baking in the oven. And now, thanks to a British chemist, a handy infographic reveals the mélange of odiferous compounds that make it possible.

The Chemistry Behind That New Car Smell

Compound Interest, a blog written by Andy Brunning, a chemistry teacher in the UK, specializes in creating graphics that explain the chemical reactions we come across on a day-to-day basis. (Why does catnip drive cats crazy? What's materials give the World Cup ball its bounce?)

His latest exploration of compound molecules is the new car smell:

Several studies have been carried out on 'new car smell', and a large number of volatile organic compounds (VOCs) have been detected during this research. The estimated number of compounds varies wildly: several studies quote in the region of 50-60 volatile organic compounds, with one or two even venturing well over 100. But where do these compounds come from?

The majority of the compounds originate from the various parts of the new car. Chemicals used to make carpets, upholstery, plastics and adhesives used in the car can all contribute to the VOCs present via a process known as "off-gassing," by which they release fumes into the atmosphere. The precise compounds will depend on the materials used in manufacture, and so will vary in different brands of car. Additionally, some of these compounds may be odorless, but a large number may contribute in some way to the "new car smell."

Studies are conflicting as to whether these compounds are harmful to human health at the levels present…. however, the worst noted effects are headaches, drowsiness and mild allergic responses—and these can be minimized by ensuring adequate ventilation in very new cars. Even if you sit in your brand new car hyperventilating, you're not going to experience anything worse than this. Car manufacturers are now also actively working to reduce VOC concentrations in new car interiors.

Read more at the Compound Interest blog.