By Sid Perkins
Pollutants generated by human activity in Europe significantly boost ozone concentrations downwind, adversely affecting human health and causing thousands of premature deaths, a new study suggests.
The strong sunshine around the Mediterranean accelerates the chemical reactions that transform various industrial and vehicular emissions into ozone. When emissions generated in Europe are added to those produced locally in North Africa, the Near East and the Middle East, pollution levels can easily reach those considered unhealthy by European health standards, says Bryan N. Duncan, an atmospheric chemist at NASA’s Goddard Space Flight Center in Greenbelt, Md. Under European standards, average ozone concentrations shouldn’t exceed 60 parts per billion for an eight-hour period, he notes.
Duncan and his colleagues used a computer model to simulate 223 of the chemical reactions that take place between and among 82 different types of emissions, including those that generate ozone.
The model suggests, for example, that ozone concentrations in North Africa often are between 10 and 20 ppb higher than they would be if European emissions didn’t waft to the region, Duncan reported Wednesday in Fort Lauderdale, Fla., at a meeting of the American Geophysical Union.
That extra pollution causes ozone concentrations in North Africa and the Near East to violate European health standards 70 to 150 times more often each year than the concentrations would if the area didn’t receive emissions from Europe, the researchers estimate.
Epidemiological analyses suggest that ozone resulting from European pollutants causes more than 51,000 premature deaths each year, Duncan says. Interestingly, about 32,000 of those fatalities occur outside Europe itself, and around 19,000 of them occur in North Africa, the Near East and the Middle East.
