ANN ARBOR, Mich. — The Ecology Center has expanded its HealthyCar.org database to include vehicles from the 2008 and 2009 model years, finding that some companies have made gains in taking chemicals out of their cars.

The nonprofit tested more than 220 vehicles for the second installment of it guide to chemicals that off-gas from car parts. The group also released the newest version of a report examining the same chemicals in car seats.

The Ecology Center looked for bromine, chlorine, lead and heavy metals such as chromium, copper, mercury and nickel. Bromine is associated with brominated flame retardants (BFRs), which add flame resistance to plastics, and chlorine, which indicates the presence of PVC and phthalates.

The Ecology Center tested 11 components in each vehicle, parts that people mostly commonly come into contact with like the steering wheel, shift knob, armrest/center console, dashboard, carpet and seat.

Vehicles and car seats are scored on a range of 0-5, with 5 meaning there is high concern over the chemical contents.

Mazda, General Motors and Nissan are highlighted as making some of the biggest improvements, with GM's overall vehicle rating improving 27 percent. The average score for children's car seats also rose by 28 percent.

The vehicles of least concern for 2008-2009 are the 2008 Acura RDX and 2008 Smart Pure, which both scored .6, and the vehicles with highest concern are the 2009 Mitsubishi Eclipse Spider, at 4.7, and the 2008 Suzuki Reno, at 4.3.

The range of scores is slightly different than in 2006-2007, when the lowest score was .5 and the highest was 5.