New Car Smell - Chemical Composition

Chemical Composition

Both the scent and what produces it vary somewhat in different kinds of cars. Most of the interior of an automobile consists of plastic held together with a number of adhesives and sealers. When the car is first manufactured, these materials are left slightly unstable, and continue to release volatile organic compounds into the air afterward (cf. outgassing). These fumes may also come from phthalates and other plastic-softening chemicals (plasticizers) that evaporate (or outgas) over time.

In 2012, the Ecology Center, a Michigan-based nonprofit environmental organization tested more than 200 2011- and 2012-model year vehicles for chemicals such as "bromine (associated with brominated flame retardants, or BFRs), chlorine (indicating the presence of polyvinyl chloride, or PVC and plasticizers), lead, and heavy metals that off-gas from parts such as the steering wheel, dashboard, armrests and seats" and produced a ranking table.

Scientists who have studied the chemicals released recommend keeping new cars well ventilated while driving, especially during the summer. A 1995 analysis of the air from a new Lincoln Continental found over 50 volatile organic compounds, which were identified as coming from sources such as cleaning and lubricating compounds, paint, carpeting, leather and vinyl treatments, latex glue, and gasoline and exhaust fumes. An analysis two months after the initial one found a significant reduction in the chemicals. The researchers observed that the potential toxicity of many of these compounds could pose a danger to human health.

In a paper published in 2000 by researchers at the University of Texas at Austin, total volatile organic compound levels as high as 7,500 micrograms per cubic meter were measured in one new vehicle on the first day of sampling. Concentrations decayed approximately 90% over a three-week period. Over sixty chemicals were identified inside the interiors of the four vehicles in this study.

In some instances the odor can actually result from a manufacturing defect. According to official documents of Bentley Motors (BT26), there was an "obnoxious odor" in Bentley cars for model years 1999-2002. The smell emanated from a rust inhibitor that was used by Bentley during that time.