The effect of last month's strike on users of public transport varied from mild nuisance to intense distress. On the bright side there was a tangible absence of choking black fumes as the streets were healthier for three entire days - when the strikers were not burning up diesel and making a general spectacle of themselves.

Emissions from cars, trucks and buses continue to be the main source of health-damaging air pollutants in EU countries, according to a new report by the European Environment Agency. After the construction sector, traffic is the most important source of fine particulate emissions (PM10 and PM2.5), which can cause respiratory diseases in humans.

Anyone with a nose could tell that pollution was markedly less in many areas when buses were not clogging roads and lungs with their trademark fumes during the bus strike.

Official data from the Malta Environment and Planning Authority's monitoring station at the traffic hub in Msida is not yet available online to confirm this simple observation. The authority expects to solve technical problems which have so far prevented the data being made accessible in real time very soon.

Readings may have been skewed with more private vehicles on the road in some areas while striking public transport vehicles paraded in others. It is difficult to tell without data on traffic counts which would detect an increase in private car use during the strike. Effects of wind direction and storms or volcanic eruptions in neighbouring countries would also have to be taken into account.

A government website for air quality in Cyprus makes readings available to within the last hour for downtown areas and warns those sensitive to pollution to stay indoors or use an inhaler to relieve symptoms. Air quality information is displayed on roadside panels.

Health effects of different levels of air pollution are listed and a useful graph shows pollution monitoring results at urban sites in Cyprus compared to those in other European cities.

The most notable feature of the Cypriot air quality website is the limit or tolerance value, shown as a red line against which figures are set, making it easier to see where limits have been exceeded. The Mepa readings could be made clearer by adding this feature. At present, limit values are shown on a separate page while the average citizen struggles to make sense of the numbers with no immediate reference point at hand.

Data from the station monitoring pollution from the power plant at Marsa is not yet available online. A Mepa spokesman explained that the station was in the process of being upgraded to weblogging so that data could be made available "in the very near future".

The government has up until October to justify its request for a time extension on the particulates directive. Extensions will be granted only for zones with external factors over which the member states have no control, such as transboundary contributions and adverse climatic conditions.

In some instances it has been said that emissions of particulates are high due to Malta 's position close to sandy deserts and salty sea spray. Cyprus , in a similar position, also experiences Sahara sand, sea salt and fine soil blown from rural areas as natural causes of PM10.

A University of Stuttgart study has shown that 17 per cent of cases where PM10 was over the limit were caused by Sahara sand. Yet at a busy traffic site in Famagusta over half of the particulates measured were identified as coming from traffic. The study concluded that traffic was the main anthropogenic (man-made) source of this pollution and therefore measures to reduce traffic emissions had to be put in place.

A similar study could be helpful for Malta . Particulates from any source, including the building industry, are unhealthy since they act as conveyors of other pollutants into the lung.

Road transport remains the single most important source of air pollution in Europe , according to the European Environment Agency. While air quality in the EU has improved, pollution levels are still high enough to damage human health and the environment, particularly in urban areas.

Euro 5 and Euro 6 standards are part of a broader strategy on clean air, aiming to reduce illnesses and cut the number of premature deaths related to pollutant emissions by 50,000 over 20 years. This would also save the EU at least €42 billion per year in health costs.

Legislation binding the Malta Resources Authority to set up a system for monitoring the quality of fuel in line with EU directives has not been fully activated. A report on national fuel quality was to have been submitted to the ministry each year. In 2005, the recorded limit values were exceeded several times. In particular, nearly 75 per cent of diesel samples failed to comply with the sulphur limit.