A doctor in Germany has admitted mistakes in his controversial study calling on Brussels to rethink air pollution limits.
Dieter Köhler, the ex-president of the Germany Society of Pneumology, acknowledged miscalculations in research that claimed there was “no scientific justification” for restrictions on nitrogen oxides and particulate matter.
Professor Köhler, speaking to German newspaper Die Tageszeitung, which uncovered the error, explained himself by saying: “I practically do everything by myself and, as a pensioner, I don't even have a secretary anymore.”
Köhler sparked debate in Germany by publishing a letter in January calling for air pollution limits to be reviewed.
Only 112 out of 3,800 lung doctors put their names to the study but it prompted Germany’s transport minister, Andreas Scheuer, to write a letter to the European Commission to ask for a review of limits.
The premise of the study was the claim that a non-smoking 80-year-old would breathe in a similar amount of nitrogen oxide over the course of his or her life as a regular smoker does in several months.
The implication was that because regular smokers don’t tend to die from such short-term exposure, air pollution limits must be too high.
But Die Tageszeitung scrutinised the figures and found a regular smoker would inhale a comparable amount of nitrogen oxide — as the 80-year-old — over the course of six to 32 years, rather than a matter of months.
Germany has been at the centre of Europe’s air pollution story over recent years.
Volkswagen admitted in 2015 that diesel cars it sold in the US were fitted with devices to cheat emissions tests.
It has contributed to a move away from diesel, which experts believe is more harmful to human health.
Diesel cars are believed to admit more nitrogen oxides, which cause respiratory problems, and particulate matter, that is said to be carcinogenic.
Several German cities have banned older diesel cars from their streets in a bid to tackle air pollution problems.