Ecological Effects of Air Pollution Ellen Chris Crystal

Introduction

Why is PM important? (You’re really asking? ;) ) It is widely accepted that particulate matter (PM) has damaging affects on respiratory health. Given that PM is harmful to human health, let’s look at the causes of exposure and the extent to which pedestrians and bicyclists experience it. Picture courtesy of Tesa-clean-air.com

There were “…no differences in…PM2.5, or PM10 concentrations between driver[s] and cyclist[s], but [the study] reported four times higher respiratory exposure to cyclists from increased particle deposition as a result of elevated breathing rates during exercise.” Quiros et al. (2013). Ultrafine particle exposures while walking, cycling, and driving along an urban residential roadway. Atmospheric Environment, 73, 186. This reinforces my previous conclusion about the role of one’s mode of transportation (on foot, bike, vehicle) in moderating his or her exposure to PM.

“PM2.5 respiratory exposures…are functions of…arithmetic concentration…to which the individual is exposed, the length of each trip…, and gender-average breathing rates…130, 390, and 580 mL s^-1 for driving, walking, and cycling modes, respectively.” Quiros et al. (2013). Ultrafine particle exposures while walking, cycling, and driving along an urban residential roadway. Atmospheric Environment, 73, 187. Looking at breathing rate helps determine a person’s exposure to PM. One engaging in physical activity (i.e. cycling or walking) breathes heavier than one who’s driving. The faster you breathe, the greater your potential for PM inhalation.

 Table 1  UFP and PM2.5 concentration and respiratory exposures categorized by mode and period. The units for each category as specified under each column heading. GSD denotes  geometric standard deviation; SD denotes one arithmetic standard deviation.  UFP PM2.5  Average concentration geometric  mean (GSD) [# cm3]  Respiratory exposure arithmetic  mean SD [# inhaled trip1]  Average concentration arithmetic  mean SD [mg m-3]  Respiratory exposure arithmetic  mean SD [mg inhaled trip1]  Walking, 25 min trip1  Morning (1.83)  Afternoon (1.73) þ 5.59  Evening (1.64) þ 6.12  Cycling, 7 min trip1  Morning (1.85)  Afternoon (1.77)  Evening (1.98)  Driving with windows OPEN, 4 min trip1  Morning (1.95)  Afternoon (1.98)  Evening (1.85)  Driving with windows CLOSED, 4 min trip1  Morning (2.73)  Afternoon (1.97)  Evening (1.94)

Trees

Chemistry  Photosynthesis  Carbon  Oxygen  Carbon sequestration  Pg of carbon per year  Biomass of trees  VOC

Deforestation  Developing countries  Tropical rainforests  Pg C in 1990s  Pg C  Industrial agriculture  Palm  Cattle

Slash & Burn

Global carbon emissions