NCT01708356

Brief Summary

Introduction: Cycling is currently promoted at the municipal, provincial and national level as a form of active transportation that increases physical activity while at the same time reducing traffic congestion, traffic-related air pollution and greenhouse gas emissions. While at a population level the health benefits of exercise via cycling are estimated to substantially exceed any health impacts related to air pollution exposure and injuries from traffic accidents , cyclists are known to experience elevated exposures to traffic-related air pollutants. Combined with exposure to elevated concentrations of air pollutants, cyclists also are subject to substantially increased inhaled doses due to their level of exertion and consequently increased inhalation rate. Therefore, given that cyclists experience exposures to relatively high concentrations of traffic-related air pollutants and that their inhalation of these pollutants is increased, it is important to evaluate the potential health impacts of this scenario. Research on the potential health impacts related to exercise (cycling) and urban air pollution exposure can help inform public communication strategies related to air quality and its health impacts. In addition, as our previous work suggests substantial variability in air pollution exposures to cyclists that is related to the route type and the levels of traffic along cycling routes, there is potential for transportation planners to promote increased cycling by enhancing infrastructure while at the same time developing routes that also minimize exposure to air pollution. The cyclist population is also interested in information regarding the air pollution exposures and potential health impacts related to cycling. The objective of this study is to investigate the relationship between traffic-related air pollution exposure, and respiratory and cardiovascular health impacts in commuting cyclists. Specifically, the investigators propose to:

  1. 1.determine commuting cyclists' exposure to traffic-related air pollutants (PM 2.5, PM10, ultrafine particulate, black carbon) while cycling along two different bicycle routes in the city of Vancouver;
  2. 2.estimate the pollutant dose received by each cyclist, and relate this to the health effects observed; and
  3. 3.determine if there is a change in lung function, endothelial function, and C-reactive protein level related to the level of air pollution exposure and dose

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
38

participants targeted

Target at P25-P50 for not_applicable

Timeline
Completed

Started Jun 2010

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

June 1, 2010

Completed
1.4 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

November 1, 2011

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

November 1, 2011

Completed
11 months until next milestone

First Submitted

Initial submission to the registry

October 9, 2012

Completed
7 days until next milestone

First Posted

Study publicly available on registry

October 16, 2012

Completed
Last Updated

October 16, 2012

Status Verified

October 1, 2012

Enrollment Period

1.4 years

First QC Date

October 9, 2012

Last Update Submit

October 15, 2012

Conditions

Keywords

Air PollutionParticulate MatterExerciseRespiratory RateInflammationOxidative StressPlethysmography

Outcome Measures

Primary Outcomes (1)

  • Change in endothelial function, as measured by peripheral arterial tonometry (EndoPAT) score of reactive hyperemia index (RHI)

    Baseline (1 hour pre-expousre) and 1 hour post- exposure (plus or minus 30 minutes) to a bicycle ride in an urban environment outdoors

Secondary Outcomes (1)

  • Change in lung function (using spirometry to assess lung function values)

    Baseline (1 hour pre-exposure) and 1 hour post- exposure (plus or minus 30 minutes) to a bicycle ride in an urban environment outdoors

Other Outcomes (3)

  • Change in blood levels of C-reactive protein (a marker of systemic inflammation)

    Baseline (1 hour pre-exposure) and 1 hour post- exposure (plus or minus 30 minutes) to a bicycle ride in an urban environment outdoors

  • Change in blood levels of Interleukin-6 (a marker of systemic inflammation)

    Baseline (1 hour pre-exposure) and 1 hour post- exposure (plus or minus 30 minutes) to a bicycle ride in an urban environment outdoors

  • Change in blood levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG)(a marker of oxidative stress)

    Baseline (1 hour pre-exposure) and 1 hour post- exposure (plus or minus 30 minutes) to a bicycle ride in an urban environment outdoors

Study Arms (1)

Normal cycling

EXPERIMENTAL

Cycling on a residential and downtown route (crossover design)

Behavioral: Cycling on a residential route

Interventions

Normal cycling

Eligibility Criteria

Age19 Years - 39 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64)

You may qualify if:

  • Age 19- 39
  • male or female
  • able to bicycle comfortably on city streets for 1 hour

You may not qualify if:

  • Smokers of any substance (smoking more than 1x every 2 weeks)
  • Must be of height to safely ride a test bike (\<5'2", \>6'5" )
  • Diagnosed asthma or active allergy (hav fever) symptoms
  • Irregular menstrual cycle, pregnant, breastfeeding, non-monocyclic contraceptive medication or device
  • Taking medication for heart or lung condition
  • Answers yes to any questions on physical activity readiness questionnaire (PAR-Q)
  • requires pain medication daily
  • visual or hearing impairment that prevents safe cycling on streets with motor vehicles

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Air Pollution Exposure Lab, Vancouver General Hospital through the School of Population and Public Health, University of British Columbia

Vancouver, British Columbia, V6T 1Z3, Canada

Location

Related Publications (1)

  • Cole CA, Carlsten C, Koehle M, Brauer M. Particulate matter exposure and health impacts of urban cyclists: a randomized crossover study. Environ Health. 2018 Nov 14;17(1):78. doi: 10.1186/s12940-018-0424-8.

MeSH Terms

Conditions

Motor ActivityInflammation

Condition Hierarchy (Ancestors)

BehaviorPathologic ProcessesPathological Conditions, Signs and Symptoms

Study Officials

  • Michael Brauer, ScD

    The University of British Columbia

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
NONE
Purpose
PREVENTION
Intervention Model
CROSSOVER
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

October 9, 2012

First Posted

October 16, 2012

Study Start

June 1, 2010

Primary Completion

November 1, 2011

Study Completion

November 1, 2011

Last Updated

October 16, 2012

Record last verified: 2012-10

Locations