Microenvironment particle measurements in Thessaloniki, Greece

Monitoring of particulate concentrations in Thessaloniki, Greece, was carried out during April 2011, to assess differences in commuters' exposure to traffic related particulate pollution. Three routes were monitored in the two directions while bicycling, driving car and travelling by bus. The length of each route was about 8 km and individual journey times ranged between 18 and 34 min. Car trips were made with windows closed and with the ventilation system at moderate setting and with co-driver's window open. The results indicate that mean inhalation doses while bicycling is higher than those during travelling by bus (15% for PM, 55% for black carbon and 40% for particle number) and by car (60% open window - 70% closed window for PM, 50% open window - 78% closed-window for black carbon and 54% open window - 77% closed window for PN). Individuals who change their travel mode from car to bicycling and bus commuting in response to policies aimed at encouraging a modal shift in travel behavior, are thus likely to experience increased journey-time personal exposures to traffic-related air pollution. Commuting by car with closed windows is the transport mode by which a person experiences the least exposure to particulate pollution.