TY - JOUR

T1 - Inhaled particle counts on bicycle commute routes of low and high proximity to motorised traffic

AU - Cole-Hunter, Tom

AU - Morawska, Lidia

AU - Stewart, Ian

AU - Jayaratne, Rohan

AU - Solomon, Colin

PY - 2012/12

Y1 - 2012/12

N2 - Frequent exposure to ultrafine particles (UFP) is associated with detrimental effects on cardiopulmonary function and health. UFP dose and therefore the associated health risk are a factor of exposure frequency, duration, and magnitude of (therefore also proximity to) a UFP emission source. Bicycle commuters using on-road routes during peak traffic times are sharing a microenvironment with high levels of motorised traffic, a major UFP emission source. Inhaled particle counts were measured on popular pre-identified bicycle commute route alterations of low (LOW) and high (HIGH) proximity to motorised traffic to the same inner-city destination at peak commute traffic times. During commute, real-time particle number concentration (PNC; mostly in the UFP range) and particle diameter (PD), heart rate, geographical location, and meteorological variables were measured. To determine inhaled particle counts, ventilation rate was calculated from heart-rate-ventilation associations, produced from periodic exercise testing. Total mean PNC of LOW, compared to HIGH, was reduced (1.56 × e 4 ± 0.38 × e 4 versus 3.06 × e 4 ± 0.53 × e 4 ppcc; p = 0.012). Total estimated ventilation rate did not differ significantly between LOW and HIGH (43 ± 5 versus 46 ± 9 L min -1; p = 0.136); however, due to total mean PNC, minute inhaled particle counts were 48% lower in LOW, compared to HIGH (6.71 × e 8 ± 1.30 × e 8 versus 14.08 × e 8 ± 1.77 × e 8 particles total; p = 0.003). For bicycle commuting at peak morning commute times, inhaled particle counts and therefore cardiopulmonary health risk may be substantially reduced by decreasing proximity to motorised traffic, which should be considered by both bicycle commuters and urban planners.

AB - Frequent exposure to ultrafine particles (UFP) is associated with detrimental effects on cardiopulmonary function and health. UFP dose and therefore the associated health risk are a factor of exposure frequency, duration, and magnitude of (therefore also proximity to) a UFP emission source. Bicycle commuters using on-road routes during peak traffic times are sharing a microenvironment with high levels of motorised traffic, a major UFP emission source. Inhaled particle counts were measured on popular pre-identified bicycle commute route alterations of low (LOW) and high (HIGH) proximity to motorised traffic to the same inner-city destination at peak commute traffic times. During commute, real-time particle number concentration (PNC; mostly in the UFP range) and particle diameter (PD), heart rate, geographical location, and meteorological variables were measured. To determine inhaled particle counts, ventilation rate was calculated from heart-rate-ventilation associations, produced from periodic exercise testing. Total mean PNC of LOW, compared to HIGH, was reduced (1.56 × e 4 ± 0.38 × e 4 versus 3.06 × e 4 ± 0.53 × e 4 ppcc; p = 0.012). Total estimated ventilation rate did not differ significantly between LOW and HIGH (43 ± 5 versus 46 ± 9 L min -1; p = 0.136); however, due to total mean PNC, minute inhaled particle counts were 48% lower in LOW, compared to HIGH (6.71 × e 8 ± 1.30 × e 8 versus 14.08 × e 8 ± 1.77 × e 8 particles total; p = 0.003). For bicycle commuting at peak morning commute times, inhaled particle counts and therefore cardiopulmonary health risk may be substantially reduced by decreasing proximity to motorised traffic, which should be considered by both bicycle commuters and urban planners.

KW - Bicycle commuting

KW - Bpm

KW - CBD

KW - Exposure concentration

KW - Inhaled particle count

KW - Motorised traffic

KW - PD

KW - PM

KW - PNC

KW - Ppcc

KW - UFP

KW - Ultrafine particles

UR - http://www.scopus.com/inward/record.url?scp=84864530347&partnerID=8YFLogxK

U2 - 10.1016/j.atmosenv.2012.06.041

DO - 10.1016/j.atmosenv.2012.06.041

M3 - Journal article

AN - SCOPUS:84864530347

VL - 61

SP - 197

EP - 203

JO - Atmospheric Environment

JF - Atmospheric Environment

SN - 1352-2310

ER -