Potential pollution exposure reductions from small-distance bicycle lane separations

Abstract

Abstract Many studies have compared the exposure of cyclists to those taking other modes of transport and compared exposure differences between backstreet routes and main roads. In this study, we employ the use of three bicycles travelling in unison to sample concentrations of ultrafine particles (UFPs), carbon monoxide (CO) and fine particulate matter (PM1.0) at three different distances from the traffic flow, in a central city park area of Christchurch, New Zealand. Similar research has been done using stationary equipment, but this may not accurately represent exposure differences while moving with a stream of vehicles. Three cyclists were equipped with a set of identical instruments and rode continuously along a road, the road׳s sidewalk (7 m away) and an off-road path (19 m away), for a total of 6 h and 45 min, over 5 afternoon sampling runs during fall. Data were analysed in the form of linear mixed-effects models, with cyclist position (distance from edge of nearest traffic lane), wind speed, and temperature, having statistically significant effects on mean exposures (p