six companies control 91 per cent of the us automobile market. They are also responsible for more than 90 per cent of vehicular emissions in the country. This was revealed in an environmental rating of automobile companies in the us, conducted by the Union of Concerned Scientists (ucs), a non-governmental organisation. The report is based on a biennial study, which evaluated vehicle models for 2000 and 2001, by analysing their emissions of smog-forming pollutants and greenhouse gases.

Honda Motors Limited topped the ratings followed by Toyota, Nissan, Ford, General Motors and Daimler Chrysler. Vehicles from these six companies account for 93 per cent of all smog-forming pollution and 92 per cent of carbon dioxide emissions, the two major environmental problems analysed in the study. The rating is based on the relative emissions of the average new vehicle (cars, sports utility vehicles, minivans and pickups) sold by each company.

The study notes that Honda, which has seven per cent share of the us market, has retained its position since the 1998 ranking largely because it offers the best fuel economy. It has been observed that companies with sales dominated by trucks are generally bigger polluters as the currently enforced environmental regulations permit trucks to pollute more than cars.