Air Pollution

Of the four factors represented in the SRS, air pollution is the one most readily acknowledged by the general public. Most of these people, however, view the health outcomes of air pollution in relation to respiratory health. The relationship between fine particulate matter and chronic stress is a less known but arguably more serious issue due to chronic stress triggers being harder to acknowledge in real time. Fine particulate matter also comes from many sources that many may not be as aware of, such as the brake systems of cars.

Air pollution presents a particularly insidious hazard given that the disease affects respiratory and cardio-vascular systems (source). These two systems are sensitive to air pollution as air pollution directly damages the mechanics, and as a consequence the function, of lungs, heart, and the circulatory system (source).

In addition, both indoor and outdoor air pollution are main environmental hazards identified that affect not only our lungs but, in fact, our whole body. As we also breathe in the oxygen necessary to sustain life, we also breathe in harmful pollutants that enter our lungs and bloodstream to then travel through the whole of our system where they reach, virtually, all our cells (source). Pollutants directly damage our lungs and other organs, cause systemic inflammation (which can reduce the immune response), and initiate a stress response which, if chronic, can lead to subsequent damage to our bodies. Acute and chronic exposure to air pollution, therefore, weakens our whole system and depletes our body of resources that are essential to combat additional stressors.

The dangerous and important fact about fine particulate matter is that there is technically no safe amount that a person should be exposed to regularly (source). The SRS, therefore, starts the scale at zero and maxes at the WHO recommended level of particulate matter. These levels are much more conservative than some of the larger global targets but are feasible within the ranges of values London presents.