Emissions from car exhausts exceeded EU thresholds for nitrogen oxide at half of Germany’s monitoring stations. While 2014 is among the lowest years for particulates levels, the Federal Environment Agency sees no reason for relief. EurActiv Germany reports.

Nitrogen oxide, primarily originating from motor vehicle exhausts, is quickly becoming a top pollutant in Germany, according to a preliminary analysis conducted by the Federal Environment Agency (UBA).

Data collected at over 500 monitoring stations indicates that, once again, the annual mean value of more than half of the monitoring stations near high-traffic roads exceeded the threshold of 40 µg per cubic metre (m3).

This share is likely to increase considerably when more data is added in May 2015 from 124 monitoring stations to be included in the statistic. These could not yet be evaluated due to technical reasons.

“To contain threshold exceedances in nitrogen oxide, it is vital that the new exhaust norm EURO 6 also lead to lower emissions in real traffic. So far many automobile manufacturers were only able to guarantee this in the laboratory,” said UBA president Maria Krautzberger.

Although no ozone peaks were observed in the summer of 2014, there were target value exceedances in around 6% of all monitoring stations. But the maximum 8 hour mean ozone concentration should not exceed 120 µg/m3 on more than 25 days per calendar year.

At the same time, 2014 showed some the lowest levels of particulates in the air. But Krautzberger sees no room for satisfaction. “Despite low particulates values, health risks still exist. For particulates, there is no minimum effect threshold – health effects can also occur when the concentration levels of particulates is relatively low. The World Health Organization (WHO) has confirmed this again.”

The EU-wide threshold value on particulates (PM10) was only exceeded at 10% of air monitoring stations located near traffic. This means the PM10 mean daily value was over the permitted value of 50 µg/m3 on more than 35 days.

But the WHO recommends a considerably stricter particulate threshold value, at 20 µg/m3 in the yearly average. If this is applied, 48% of all monitoring stations exceeded the threshold value.

“The growing number of wood-burning heating systems has an especially negative effect on particulate pollution,” said Krautzberger. In the winter months in particular, the share of wood-fired heating can comprise up to 25% of overall particulate pollution. As a result, emissions from wood-fired heating systems have begun to generate more particulate than exhausts in highway traffic.”