North American car manufacturers are bottom of the sustainability league, according to the largest ever global study of the sector's performance.
Asian manufacturers came out best in the survey, headed by researchers from Queen's University Management School in Belfast.
The survey looked at factors such as the volume of greenhouse gas emissions from production facilities and the number of work accidents recorded by a company between 1999 and 2007.
It also looked at how efficiently automobile manufacturers used key natural resources. It caclulated the ratio of sustainable value to sales so that different companies could be compared directly, irrespective of their size.
Asian manufacturers including Toyota, Hyundai, Nissan, Honda, and Suzuki all outperformed their North American competitors. In stark contrast to the Asian manufacturers, both Ford and General Motors (GM) fell well inside negative territory, with GM the worst offender.
There was a mixed picture among European manufacturers. While BMW topped the ranking of all 17 manufacturers in most of the years assessed, other European carmakers PSA (Peugeot, Citroën), Renault, Volkswagen and DaimlerChrysler/Daimler AG only occasionally kept pace. FIAT Auto was well behind throughout the entire review period.
Ralf Barkemeyer from Queen's University Management School explained: "GM's value contributions from carbon dioxide, nitrogen oxide and sodium oxide emissions as well as waste generation are very negative during the period 1999 to 2007. Its sodium oxide value contributions show the worst level of resource efficiency in the entire study."
Professor Frank Figge from Queen's University Management School added: "The bottom line is that this study reveals big differences in sustainability performance in automobile manufacturing. This shows that the production process itself bears considerable room for improvement in terms of sustainability performance. We hope car manufacturers and governments worldwide will take note of this important study."