[mailchimp_signup][/mailchimp_signup] The report comes as EU environment ministers are due to discuss the Commission’s Euro-5 proposal, and as evidence has emerged that emissions of nitrogen oxides (NOx) are much higher than EU test cycles lead people to believe. The WHO’s air quality guidelines on particulate matter (PM) and other air pollutants propose maximum levels for both PM10 and PM2.5 that are much stricter than the current Euro-5 proposal. The guidelines for PM2.5 are 10µg/m3 as an annual average and 25µg/m3 as a daily average. For PM10 they are 20µg/m3 annual and 50µg/m3 daily. The WHO’s report says: “These are the lowest levels at which total, cardiopulmonary and lung cancer mortality have been shown to increase … in response to PM2.5 in the  American Cancer Society study.” NO NOx REDUCTION IN 13 YEARS Meanwhile research by two German technology institutes shows that “real world” NOx emissions from diesel vehicles are much higher than the figures that come from the testing procedures required under EU law for a type of vehicle to be approved. The institutes TUG and FVT, presenting their findings last month at a workshop for national experts on Euro-5, say NOx emissions were reduced much less between the Euro-1 and Euro-4 standards in real driving conditions compared with the results of type approval testing. In fact, NOx emissions have not seen a significant reduction in the last 13 years. They say part of the reason is that the test cycle relates to a much smaller area of the engine than true road driving conditions. This has allowed manufacturers to tune engines to reduce NOx only on the test cycle, a practice known as “cycle beating”. T&E policy officer Aat Peterse said: “This strengthens our argument for a stricter NOx standard for diesels. It would force car makers to use after-treatment technologies rather than just tune the engine to reduce NOx. As well as stopping cycle beating, this would have another advantage – the makers could retune their engines to optimise CO2 emissions and improve efficiency. This would reduce fuel consumption, CO2 emissions, NOx and thus particulate matter, which NOx contributes to.” The USA has much stricter standards for diesel vehicles than the EU, which means the world’s car makers are already working on cars for the US market which meet standards much stricter than those proposed in Euro-5. In a letter published in the Financial Times, Peterse said: “If unchanged, the proposed Euro-5 standard would result in European car makers exporting cleaner diesels to the US than they sell at home. To Europeans more used to bashing the US’s environmental credentials, that would be rather embarrassing!” In a fresh example, T&E’s German member VCD has congratulated Mercedes on its efforts to reduce NOx from diesels, but said its technology should be avai- lable to all markets. Mercedes unveiled its new catalytic diesel technology at this month’s Geneva motor show under the name “BlueTec”, with which it aims to break into the US diesel market. This news story is taken from the March 2006 edition of T&E Bulletin.