Nanoparticles because of their size can be hazardous to our health as they can penetrate deeper into the lungs than larger particles contributing to both cardiovascular and pulmonary diseases. A cubic centimetre can contain several thousand nanoparticles. The particles can travel long distances before they are trapped in our lungs or washed away by the rain.
For the first time, an attempt has been made to estimate the proportion of nanoparticles stemming from sea traffic by Adam Kristensson, a researcher in Aerosol Technology at the Lund University Faculty of Engineering in Sweden.
The study reported in the journal Oceanologia shows that the air along the coasts is full of hazardous nanoparticles of which 50% is from sea traffic while the rest is from cars but also biomass combustion, industries and natural particles from the sea. It was previously thought that land-based pollution from northern European countries and emissions of natural particles from the surface of the sea accounted for a much larger proportion.
The air flow from their measuring station in southern Sweden to the measuring station on the Lithuanian coast was studied. They have also studied the air flow from a station in the Finnish archipelago towards the Lithuanian station. By comparing levels of nanoparticles, the researchers can draw conclusions about the respective proportions that stem from cars and other emissions, and sea traffic.
Particles from sea traffic in the North Sea and the Baltic Sea are expected to contribute to 10 000 premature deaths every year, but Adam Kristensson stresses that this estimate is very uncertain and believes that it is important to continue to conduct these types of measurements.
“It is especially important to continue to set stricter caps on nitrogen oxides and sulphate content from ship fuel.”
Future regulations will reduce the emissions of harmful nanoparticles, especially soot particles, which are considered the most hazardous.
“This year a new regulation was introduced for the North Sea and the Baltic Sea that limits the sulphate content in fuel to 0.1%. As researchers, we still have to look at what positive effects this has had so far with regard to the particle levels.”
Source: Lund University