Does school seriously damage your health? When, besides the kids, air pollutants are present in the classroom, the answer is probably yes, recent research suggests. Average concentrations of suspended particles were well over the permissible limits for 24-hour exposure set by the European Union, a survey of schools in Greece’s capital has found. A team from the Athens National Technical University’s (NTUA) School of Chemical Engineering, under the supervision of Professor Nikos Spyrellis and Assistant Professor A. Haloulakou, studied concentrations of suspended particles over an eight-hour period. Measurements were taken during lesson hours in primary schools, where, besides the home, children spend the greater part of their day. Taken in areas of Athens with different traffic levels and housing density, the measurements showed significant concentrations of suspended particles both inside and outside the school buildings. In the school playgrounds, the average concentration of PM10 and PM2.5 (the two basic categories of suspended particles) were 95 milligrams (mg) per cubic meter and 60mg per cubic meter. Measurements within the schools fluctuated from 75 to 281mg per cubic meter for PM10 and from 22 to 199mg per cubic meter for PM2.5. In nearly all the schools, average concentrations of PM10 for eight hours of school, both within and outside the buildings, exceeded the EU limits (calculated over 24 hours), according to which daily exposure should not exceed 50mg per cubic meter. As for PM2.5, which is regarded as the most dangerous, an EU directive is in the works. Suspended particles are produced by vehicular emissions, asphalt, car tires, brake materials and factories. A large proportion of PM10 is due to public works. The «new smog,» nevertheless, which is formed by the suspended particles benzene and tropospheric ozone, poses huge health hazards. Epidemiological studies have shown that exposure to these pollutants can cause severe damage to the respiratory system, cardiovascular problems and cancer. Every year, 240,000 people in Europe are reckoned to die of particle-related diseases. The discovery of these particles in schools is worrisome, since it has been confirmed that children tend to have higher concentrations of particles in the blood compared to that of adults. Their exposure to a polluted environment can lead to retarded development of the respiratory system. The NTUA chemical engineering team plans on further studies in more schools and residential areas. A long-term aim is to estimate daily exposure to suspended particles by Attica’s children and sensitive population groups, such as elderly people and those suffering from respiratory diseases.