The relationship between particle and culturable airborne bacteria concentrations in public transportation

This study aims to determine the in-vehicle and outdoor culturable airborne bacteria concentration, fine particle (PM2.5) concentration and particle number concentration for six size ranges (0.3-0.5 mu m, >0.5-1.0 mu m, >1.0-3.0 mu m, >3.0-5.0 mu m, >5.0-10 mu m, and >10 mu m) and to assess the relation between the culturable airborne bacteria and PM2.5 concentrations in different public transport vehicles. The measurement campaign was conducted in the morning and evening onboard of the Metrobus, red-bus and outdoors. PM2.5 concentrations in the Metrobus and red-bus were observed as 58.8 +/- 10.2 mu g/m(3) and 76.2 +/- 30.9 mu g/m(3), respectively, and the outdoor value was about two times more. For both types of public transportation, the amount of internal environment particulate matter and the amount of external environment particulate matter displayed a high level of correlation (red-bus/outdoors, R=0.97; Metrobus/outdoors, R=0.88) with the particulate matter size. The concentration of Staphylococcus aureus correlated with PM2.5 concentrations in the Metrobus and Staphylococcus spp. was found to be higher in in-vehicle. The number of commuters, vehicle ventilation type and outdoor air entering the vehicles probably caused the differences in in-vehicle culturable airborne bacteria and particle concentrations

THE POTENTIAL EFFECT OF THE REGULATION FOR THE END OF LIFE VEHICLES (ELV) ON GREENHOUSE GAS EMISSION SOURCED FROM CARS

One of the most important environmental problems in the world is the increasing of greenhouse gas emissions. The biggest part of greenhouse gas emissions is caused by energy sector in the word. Additionally, transportation in the energy sector is the essential source of the man made emission of greenhouse gasses. Because of the rising of population and the development of technology, the emission of greenhouse gases has been rising. It's very important to invest in new technologies along with the enforcements of new regulations. In this study, the regulations about the end of life vehicles (ELV), applied in Turkey in 2003, was assessed as a model and the same model was applied in 2010 to predict the effect on greenhouse gas emission. Vehicles over 20 years have been accepted as ELV. Greenhouse gas emissions were calculated for two situations; ELV regulation is prevailed or not. In case of applying the ELV regulation, two approaches were accepted; (1) 30% of vehicles over 20 years will be disposed off, (2) a new car will be in traffic for each ELV which disposed off. The decrease of greenhouse emissions in 2010 and 2011 were examined as 0.3 % and 1.9 % for CO(2); 1.2 % and 3.8 % for N(2)O; 3.9 % and 12.8 % for CH(4); 5.3 % and 17.6 % for CO; 3.6 % and 12.4 % for NOx; 5.6 % and 18.4 % for HC, respectively. 50 % of road transport is consisted of cars. If all the vehicles were evaluated within ELV regulation, the decrease of greenhouse emission might be 2 times more