# Energy, Society, and the Environment/Fine Air Particulates and Subsequent Effect on Mortality/Morbidity
## Particulate Matter (PM)

Particulate Matter (PM) refers to small hazardous particles which can be concentrated to varying degrees in breathable air. Generally fine particulate matter is categorized by size using PM with a subscript of the largest diameter size permissible to that category (PM$_1$, PM$_{2.5}$, PM$_{10}$) (Zhang, 2016). The size of these categories are measured in μm of diameter and can have different compounds categorized in them. Specifically PM$_{2.5}$ is of importance because it is believed to pose the greatest health risk, and in it is many compounds that are expelled through various industries into the environment. PM$_{2.5}$ can be of a primary or secondary source, primary sources are considered those which have been directly expelled into the air during an industrial process whereas secondary sources are those of which have been formed due to reactions between already existing gaseous pollutants like sulfates, and nitric oxides (Zhang, 2016). Particulate matter tends to be large enough to refract light and is the largest cause for smog and poor visibility in cities and heavily industrialized areas.

### Health Risks

According to the World Health Organization (WHO) approximately 7 million people die due to air pollution each year. Of the 7 million it is estimated that 4.2 million people die due to poor ambient (outdoor) air quality (World Health Organization). Particulate matter is small enough that it can remain airborne for large amounts of time giving better chance to be inhaled. Along with poor air quality, many of the particulates that remain in the air also contribute to altering the climate which can affect many facets of life such as agriculture to further contribute to their effect on health (World Health Organization). Particulate matter appears to have a significant effect on mortality and morbidity; increasing chances of being diagnosed with cancers, respiratory issues (such as COPD), stroke, heart disease, and pulmonary disorders (Laden et al, 2006). Currently the WHO estimates that 90% of people are living in areas with particulate concentration higher than the maximum recommended (World Health Organization).

### Prevention and Repair

As stated earlier these particulates are heavily supplied by industrial activity associated with the burning of coal and fossil fuels (Zhang, 2016). This indicates that green initiatives could be implemented to mitigate the increased output of these particulates.
Zhang, Z. (2016). "Emission Standards and Control of PM$_{2.5}$ From Coal-Fired Power Plant". IEA Clean Coal Centre.
World Health Organization (WHO). "Air Pollution". Gotten on March 18th from: https://www.who.int/health-topics/air-pollution#tab=tab_1
Laden, F., Schwartz, J., Speizer, F. E. & Dockery, D. W. "Reduction in fine particulate air pollution and mortality: extended follow-up of the Harvard six cities study". Am. J. Respir. Crit. Care Med. 173, 667–672 (2006).
United States Environmental Protection Agency: https://www.epa.gov/pm-pollution/particulate-matter-pm-basics
United States Environmental Protection Agency. "Particle Pollution and Your Health". Brochure Available at: https://nepis.epa.gov/Exe/ZyPDF.cgi?Dockey=P1001EX6.txt