Air Pollution And Its Effects On Health

In the past decade, the severe air pollution problem in fast developing countries, particularly in China, has caused highly social and scientific attention. In 2014, 92 % of the world population are exposed over to the WHO Air Quality Guidelines (AQG) PM2.5 concentration level of 10 μg/m3 (World Health Organization, 2016). Ambient particulate matter (PM) pollution ranked as the third leading risk factor in India and Nepal, and ranked as the fifth in China (GBD 2015 Risk Factors Collaborators, 2016). In 2012, about 3 million deaths globally were attributed solely to ambient air pollution, and around 87% of it occurred in low- and middle-income countries (World Health Organization, 2016).

Over the past decade, particulate matter (PM) is increasing the air pollution at an exceeding

Air pollution has been recognized as a major threat to environmental health, and the effects that it can have on the population are extremely varied. In the environmental aspects, air

Evidence suggests a role for particles and other traffic-related components in particular (Chiu et al, 2014). Exposure to environmental toxicants, such as air pollution starting in utero, couple potentially alter course of lung growth and affect both the structure and function of the respiratory system. Studies link prenatal air pollution exposure, including fine particulate matter and polycyclic aromatic hydrocarbons, with wheeze, respiratory tract infections, and reduced lung function in

Everyone in the New York metropolitan area breathes air that fails to meet the health standards, and citizens suffer serious health impact from breathing that dirty air. The relationship between air pollution and health affects everyone. Air pollution is constantly affecting people and putting them at sick, even though the degree of pollution is not at its highest. The public health significance of smoke, dust, gas, pollen, and microorganisms in the air are with a range of adverse health effects. These diseases spread and cause new disease to originate. Exposure to common urban air link to a wide range of adverse health outcomes, including respiratory and cardiovascular diseases, asthma exacerbation, reduced lung function and premature death.

The Clean Air Act enforces several programs that protect public health by regulating emission of hazardous air pollutants. These programs focus on many factors designed to improve public health and the environment. One focus includes the reduction of outdoor air pollutants that are responsible for causing acid rain, haze, smog, and other issues. Another requires the progressive elimination of production and use of chemicals proven responsible for depletion of the stratospheric ozone. The CAA also aims to reduce emissions of hazardous air pollutants that are suspected or known to cause detrimental health effects, including asthma and cancer. The most serious health risks are associated with two of the six common pollutants: particles and ozone. The efforts of the CAA have led to drastic improvements in the levels of these two pollutants. Between 1980 and 2012, the EPA found that national concentrations of ozone improved by 25%. Particle concentrations began being measured in 2000, and it was found that between 2000 and 2012, fine particle concentrations improved 37% and coarse particle concentrations improved 27% (2015). Due to these improvements, Americans inhale lower amounts of dangerous pollutants, which led to the prevention of 205,000 premature deaths solely in the year 1990 (U.S. Environmental Protection Agency,

Size of particulates in air pollution also play a major factor in the exacerbation of lung diseases. Studies shown a correlation between air particulate size (10pg/m3) and a 10% to 25 % increase in bronchitis or chronic cough in patients with COPD9.

Epidemiologic studies have determined that the following are the major air pollutants contributing to respiratory diseases: sulfur dioxide (SO2), nitrogen dioxide (NO2), ozone (O3), and particulate matter (PM) less than 10 mm and less than 2. 5 mm in diameter (PM10 and PM2.5, respectively) (Baldi et al., 1999; Chew et al., 1999; McConnell et al., 1999; McDonnell et al., 1999; Neukirch et al., 1998; Ostro et al., 1998; Sheppard et al., 1999; Taggart et al., 1996). Particulate matter is the product of solid and liquid particles being directly emitted into the air from such things as diesel engine soot, road and agricultural dust, and manufacturing processes, while SO2, NO2, and O3, are predominately byproducts of fuel combustion.

The World Health Organization estimated that more than 800,000 deaths worldwide were due to outdoor air pollution. Air pollution is a growing issue in industrialized areas due to exposure from industrial and traffic sources. Harm to the human body occurs from exposure to and inhalation of particulate matter (PM) (Barnes et al., 2012). PM is liquid or solid particles in the air, that when small enough in size, can be harmful to the human body when inhaled. Two common sizes of particulate matter are PM_10 and PM_2.5. PM_10 are particles that are 2.5 to 10 micrometers in size, and includes dust, mold and pollen just to name a few. PM_2.5 are particles that are 2.5 micrometers or smaller in size, and consists of particles from vehicles, industries, and burning. Smaller particles are able to get into the lungs and potentially cause serious health problems (Environmental Protection Agency [EPA], 2015). These health problems include acute cardiovascular events, changes to blood pressure, coagulation, myocardial perfusion, and chronic respiratory diseases (Barnes et al., 2012).

Epidemiologic studies have indicated that air pollution can induce COPD exacerbations. The increased concentration of dioxide (SO2) and nitrogen dioxide (NO2) in particulate matter up to 10 μm in aerodynamic diameter, and black smoke particulate matter can increase respiratory mortality in patients with COPD [113, 114]. Some clinical studies showed that air pollution may account for approximately 6 to 9% of admissions, depending on the time of year [114]. Patients with COPD have also been shown to be at increased risk of death associated with urban particle air pollution [115]. Studies in vitro have shown that diesel exhaust particles stimulated production of pro-inflammatory cytokines such as GM-CSF and IL-8. These cytokines may be involved

Thus, deposition of PM2.5 on alveoli was found to trigger an inflammatory response and oxidative stress, accompanied with the release of a host of pro-inflammatory mediators, vasoactive molecules and reactive oxygen species into the circulation. These will subsequently affect the vascular integrity and induce thrombogenesis138, 140. Also, it has been proposed that PM2.5 can modulate the autonomic nervous system and result in increased vasoconstriction and change heart rate variability, which will potentially enhance the risk of developing arrhythmias and thrombosis141. Importantly, it has been found that the dose-response relationship between particulate matter exposure and cardiovascular mortality is also non-linear142. In fact, the observed dose-response curve was steep at low levels, suggesting that a consequential adverse cardiovascular outcome can happen as a result of exposure to low levels142. Interestingly, a study suggested that PM2.5 is responsible for more than 90% of the predicted harm caused by thirdhand smoke pollutants143. In summary, clearly, there is substantial evidence in the literature that PM2.5 from ambient air pollution and smoking exerts harmful effects on the cardiovascular system. However, whether e-cigarettes PM2.5 produces similar effects is not known yet, but warrants investigation. This notion is

Among all the air pollutants in ambient air, PM affects more people than any other pollutant. The effects of PM on the public health occur at experienced levels of exposure currently by most urban and rural inhabitants in both developed and developing countries. (Bhola Gurjar, 2010) The major toxic elements of PM included sulfates, nitrates; ammonia, sodium chloride, and carbon, mineral organic and inorganic substances are inhaled toxic air with every breath. Chronic exposure of these particles can increase the chances for the public to develop the following medical issues:

Bhatnagar explains that majority of the chemicals that are linked to lung cancer are absent in these products, however, particulate matter remains which is what we should be concerned about. He describes the particulate matter as “small particles found in the atmosphere and is what is responsible for the health effects of air pollution.” His scientific approach in stating facts from various studies as well as his knowledgeable background makes him an effectively credible presenter.

When talking about air pollution we categorize the particles with the term particulate matter (PM). Suspended particulate matter (PM) is divided into three groups based on the diameter of the particle. PM2.5 refers to particles with a diameter less that 2.5 micrometers (µm), PM10 classifies particles with a diameter between 2.5 and 10 µm, and >PM10 defines particles with a diameter greater than 10 µm. The relative risk of developing cancer as a result of exposure to air pollution is generally small, but the attributable risk (relative risk multiplied by the number of exposed people) is high. Because exposure is so high ambient air pollution

“Air pollution is contamination of the indoor or outdoor environment by any chemical, physical or biological agent that modifies the natural characteristics of the atmosphere. Household combustion devices, motor vehicles, industrial facilities and forest fires are common sources of air pollution. Pollutants of major public health concern include particulate matter, carbon monoxide, ozone, nitrogen dioxide and sulfur dioxide. Outdoor and indoor air pollution cause respiratory and other diseases, which can be fatal.” (n.d world health organization para. 1)