Clearing the Air: A Review of the Effects of Particulate Matter Air Pollution on Human Health

Abstract

The World Health Organization estimates that particulate matter (PM) air pollution contributes to approximately 800,000 premature deaths each year, ranking it the 13th leading cause of mortality worldwide. However, many studies show that the relationship is deeper and far more complicated than originally thought. PM is a portion of air pollution that is made up of extremely small particles and liquid droplets containing acids, organic chemicals, metals, and soil or dust particles. PM is categorized by size and continues to be the fraction of air pollution that is most reliably associated with human disease. PM is thought to contribute to cardiovascular and cerebrovascular disease by the mechanisms of systemic inflammation, direct and indirect coagulation activation, and direct translocation into systemic circulation. The data demonstrating PM's effect on the cardiovascular system are strong. Populations subjected to long-term exposure to PM have a significantly higher cardiovascular incident and mortality rate. Short-term acute exposures subtly increase the rate of cardiovascular events within days of a pollution spike. The data are not as strong for PM's effects on cerebrovascular disease, though some data and similar mechanisms suggest a lesser result with smaller amplitude. Respiratory diseases are also exacerbated by exposure to PM. PM causes respiratory morbidity and mortality by creating oxidative stress and inflammation that leads to pulmonary anatomic and physiologic remodeling. The literature shows PM causes worsening respiratory symptoms, more frequent medication use, decreased lung function, recurrent health care utilization, and increased mortality. PM exposure has been shown to have a small but significant adverse effect on cardiovascular, respiratory, and to a lesser extent, cerebrovascular disease. These consistent results are shown by multiple studies with varying populations, protocols, and regions. The data demonstrate a dose-dependent relationship between PM and human disease, and that removal from a PM-rich environment decreases the prevalence of these diseases. While further study is needed to elucidate the effects of composition, chemistry, and the PM effect on susceptible populations, the preponderance of data shows that PM exposure causes a small but significant increase in human morbidity and mortality. Most sources agree on certain "common sense" recommendations, although there are lonely limited data to support them. Indoor PM exposure can be reduced by the usage of air conditioning and particulate filters, decreasing indoor combustion for heating and cooking, and smoking cessation. Susceptible populations, such as the elderly or asthmatics, may benefit from limiting their outdoor activity during peak traffic periods or poor air quality days. These simple changes may benefit individual patients in both short-term symptomatic control and long-term cardiovascular and respiratory complications.

Climate change and respiratory diseases

“…Comparing the current situation (1990-2009) with the baseline period , the largest increase in ozoneassociated mortality and morbidity due to climate change (4-5%) occurred in Belgium, Ireland, the Netherlands and the UK [42]. Exposure to outdoor particulate matter influenced by climate change has been associated with respiratory symptoms, decreased lung function, worsening of asthma and the development of chronic bronchitis [43]. In the Mediterranean area (Greece, Spain, Italy, etc.…”

Applying land use regression model to estimate spatial variation of PM2.5 in Beijing, China

“…proved to be associated with a wide variety of health effects such as aggravation of existing heart and lung disease and premature mortality (Anderson et al 2012;Dockery et al 1993;Jerrett et al 2005b;Pope and Dockery 2006). Several epidemiological studies (Breitner et al 2011;Hou et al 2010;Zhang et al 2013;Zhang et al 2012) have evaluated the association of exposure to particulate matter with adverse health impacts in Beijing.…”

Public health management: life expectancy and air pollution

“…(Keijzer et al, 2016) The most significant air pollutants causing increased mortality rate are particulate matter air pollutants: PM2,5 of 2,5 μm aerodynamic diameter and PM10 of 10 μm aerodynamic diameter. (Anderson et al, 2012) Dziunabek et al (2017 analyzed the high correlation between long-term inhalation exposure to the mixture of PM10, BaP, Cd, Pb and, the length of life of the people from Silesia province in Poland.…”