The 2011 Mitsubishi Outlander Sport and 2011 Chrysler 200 SC were the worst-performing vehicles this year in terms of inside air quality, according to the 2012 consumer guide to toxic chemicals in cars jointly released by the HealthyStuff website and the Ecology Center, a U.S.-based nonprofit environmental organization.

The consumer guide, the fourth of its edition, is based on the Ecology Center's tests on more than 200 of the most popular 2011/2012 model vehicles for chemicals released from such parts as the steering wheel, dashboard, armrests and seats. These chemicals are the culprit of the interior air pollution which is as great a concern as outdoor air pollution.

According to the report, chemicals of primary concern include bromine (associated with brominated flame retardants), chlorine (indicating the presence of polyvinyl chloride, or PVC and plasticizers), lead and heavy metals. Many of the chemicals can cause a variety of health problems including allergies, birth defects, impaired learning, liver toxicity and cancer.

Also read: Top 10 least toxic cars 2012

Following are the ten model vehicles which aroused the most serious health concerns from inside air pollution:

   2012 Mini Cooper S. Clubman （2012款Mini Cooper S. Clubman）

 Overall Score: 2.84

Chemical Level: Medium

Bromine: 0.4        Chlorine: 2.9        Lead: 1.3        Others: 2.1

Class: Hatchback

Manufacturer: Mini Cooper