Commuter exposure to ultrafine particles (UFPs), lung deposited surface area (LDSA), and noise in Ho Chi Minh City, Vietnam

Introduction

Transport is a main contributor to air and noise pollution, particularly in urban areas with the high number of motorized vehicles. Promoting active transport (i.e., cycling and walking) and public transport is an instrumental factor in reducing traffic-related air and noise pollution. However, commuters of these transport modes are often exposed to high air and noise pollution than other commuter groups.

Methods

The levels of exposure to UFP, LDSA, and noise during commuting of different transport modes in Ho Chi Minh City (HCMC) were measured and compared. Then, the dose of inhaled pollutants during commuting was calculated for each commuter group by considering the travel time and minute ventilation.

Results

The level of exposure to air and noise pollution varies across transport modes. Cyclists and motorcyclists were exposed to the highest level of air and noise pollution. Motorcyclists and cyclists were exposed to the highest UFP number concentrations during their trips, 3.6*10⁵ and 3.1*10⁵ particles/cm³, respectively. Car commuters were exposed to the lowest air and noise pollution level, followed by bus commuters. When considering the minute ventilation and travel time, cyclists inhaled significantly higher levels of air pollution than other commuters, followed by pedestrians, motorcyclists, bus commuters, and car users. As a result, the health impacts of exposure to traffic-related air and noise pollution for active commuters could be greater than other commuter groups.

Conclusions

Promoting active and public transport is a promising approach to improving air quality and reducing congestion in HCMC. Using these transport modes also has potential positive health effects on commuters through physical activities. However, active commuters are faced with the highest risk of exposure to high air and noise pollution levels. To promote active transport and public transport in HCMC, measures to reduce the level of exposure to air and noise pollution for these commuter groups are needed.