12 Air Pollutants that kill Millions Every Year​

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Air pollution is the presence of dangerous substances in the air, which have harmful or undesirable effects on people’s health and the environment. 

However, when it comes to air quality, do you ever find yourself asking what exactly these pollutants are? Not to mention what the health implications could be for not only yourself, but also, for your family and friends?

This article has been solely written for the purpose of answering these questions. Read on to find a quick break-down of the most common air pollutants with their pernicious health and environmental effects. 

Carbon Monoxide (CO)

Carbon Monoxide is a colourless, odourless, and tasteless toxic gas. It forms when carbon fuels are burned, either at too high a temperature or in the presence of too little oxygen. It is mainly emitted directly from idling vehicle engines and vehicle deceleration. Other sources are also from combustion in power station processes, biomass burning, as well as residential ovens, boilers, propane heaters and fireplaces.

Carbon Monoxide is particularly dangerous, as upon entering the bloodstream, it inhibits the body’s ability to carry oxygen to vital organs and tissues. Those who are particularly susceptible are infants, the elderly, and individuals with heart and respiratory diseases. Extremely high concentrations can lead to death.

This article has been solely written for the purpose of answering these questions. Read on to find a quick break-down of the most common air pollutants with their pernicious health and environmental effects.

Carbon Monoxide (CO2)

Although CO2 is a vitally important gas for natural processes – as seen in photosynthesis – the gas is also widely considered as a pollutant when associated with cars, planes, power plants, and other human activities that involve the burning of fossil fuels such as gasoline and natural gas.

This is primarily due to the fact that CO2 is the most common of the greenhouse gases, which trap the sun’s heat in the earth’s atmosphere. This in turn, has a direct influence on climate change and global warming. Indeed, since the Industrial Revolution, humanity has pumped enough CO2 into the atmosphere over the past 150 years, that current levels are higher than they have been for hundreds of thousands of years. 

It is through this transformation of the planet that increasingly higher CO2 levels will dramatically increase air pollution and its related diseases, as well as cause extreme weather events like deadly heat waves. 

Nitrogen Oxide (NOx)

Nitrogen Dioxide (NO2) is a human made air quality pollutant, which is formed through the oxidation of Nitric Oxide (NO) during combustion processes found in power generation, industrial and vehicle traffic sources. Nitrogen dioxide and nitric oxide are referred to together as oxides of nitrogen (NOx).

Growing evidence now points to Nitrogen Dioxide’s adverse effects on the respiratory system, leading to increased symptoms of bronchitis, asthma, as well as reduced lung function and growth.

What is more, NOx  dissolves in water vapour to form smog and acid rain, which damages buildings, vegetation and materials, contributing to the acidification of terrestrial and aquatic ecosystems. It is also central to the formation of fine particles or particulate matter (PM)  and ground-level ozone (O3), both of which are associated with adverse health effects.

Ozone (O3)

Ground-level ozone is formed through chemical reactions between pollutants, such as NOx, CO, and volatile organic compounds (VOCs), in the presence of sunlight – hence of its main concern during the summer months.

Ozone is one of the major components of photochemical smog and is a key health risk linked to breathing problems, asthma, reduced lung function and respiratory diseases. Apart from its effects on human health, Ozone also greatly damages vegetation, which in turn, greatly affects crop yields and contributes to overall forest decline.

Particulate Matter (PM)

Airborne particulate matter (PM) is made up of a collection of inhalable and respirable particles of varying sizes and chemicals. Particles with a diameter of less than 10 microns (PM10), including fine particles less than 2.5 microns (PM2.5) pose the greatest risks to health, as they are capable of penetrating peoples’ lungs and entering their bloodstream.

The smaller the particle, the higher the health risk, due to their ability to penetrate deeper into the respiratory and circulatory systems. Overall, PM can cause damage to the lungs, heart and brain, and has been linked to cardiovascular and respiratory diseases, such as asthma, bronchitis and emphysema.

Sources of PM include combustion engines (both diesel and petrol), solid-fuel (coal, lignite, heavy oil and biomass) combustion for energy production in households and industry, as well as other industrial activities (building, mining, manufacture of cement, ceramic and bricks, and smelting).

Sulfur Dioxide (SO2)

Sulfur Dioxide is an invisible toxic gas. It is created mainly from industrial processes, such as the generation of electricity from coal, oil or gas that contains sulphur.

Exposure to SO2 affects lung function and the respiratory system, as well as irritation of the eyes. Inflammation of the respiratory tract from SO2 can aggravate chronic bronchitis and asthma, as well as the risk of infection.

SO2 also combines with atmospheric water to form sulfuric acid – the main component of acid rain, which damages buildings, vegetation and materials.

What is more, high SO2 concentrations in the air can lead to the formation of other sulfur oxides (SOx). SOx can in turn react with other compounds in the atmosphere to create secondary particulate matter (PM2.5).

Hydrogen Sulfide (H2S)

Hydrogen sulfide (H2S) is a colorless gas best known for its characteristic odor of rotten eggs. Due to its occurrence in nature, and its production in numerous industrial activities, it is regarded as both an environmental and industrial pollutant.

H2S can cause respiratory and cardiovascular irritation with early symptoms of eye irritation, as well as headaches, nausea or vomiting even at low levels. Exposure to high concentrations can be extremely hazardous and lead to respiratory paralysis and unconsciousness, which rapidly induces death.

Additionally, H2S is a major component of the sulphur cycle. It is oxidised in the atmosphere to form SO2, which then further forms SOx. 

Ammonia (NH3)

Ammonia is a colourless gas with a pungent odour. As a part of the nitrogen cycle, its main sources are natural, such as agricultural processes – particularly livestock waste management and fertiliser production. Indoors causes can include cleaning solutions and cigarette smoke.

Low concentrations of Ammonia in the environment are normal and required for plant nutrition, however multiple issues arise as its concentration arises. This is due to its pollutive capabilities and its contribution to eutrophication and acidification of terrestrial and aquatic ecosystems.

Additionally, due to its corrosive nature, Ammonia irritates the eyes, nose, throat and respiratory tract if inhaled in small amounts, and is poisonous when in larger quantities. Moreover, NH3 forms secondary particulate matter (PM2.5), when combined with nitrates and sulphates in the atmosphere.

Volatile organic compounds (VOCs)

Volatile organic compounds (VOCs) consist of a large group of carbon-containing molecules, such as hydrocarbons, alcohols, aldehydes, and organic acids. Although also found outdoors, due to incomplete combustion processes and from emissions in volatile industry byproducts, VOCs are typically found indoors. Internal sources range from cleaners and disinfectants, air fresheners, carpets, wallpaper, pesticides, solvents, and tobacco smoke. 

Inhaling high concentrations of VOCs can cause difficulty breathing and nausea, as well as irritation to the eyes, nose and throat. Damage to the central nervous system and other organs has also been proven, with the most pernicious of cases leading to cancer. Overall, the negative effects of VOCs have been attributed as ‘Sick Building Syndrome’. Additionally, some VOCs combine with nitrogen dioxide (NO2) to form ground-level ozone (O3), which contributes to the formation of secondary particulate matter (PM2.5).

So what can we do to tackle these air pollutants and make our air cleaner?

Through the implementation of the densest and most technologically advanced network of air quality sensors in the world we can tackle air pollution together.

By providing the tools to monitor, analyse and report on air quality data, we empower local communities, regional municipalities, and national governments with the information to develop policies for a cleaner planet. 

Not only do Persium Pods provide the most accurate air quality data on the market, but also through unparalleled deep-machine learning and AI systems, which can be found in both our MapView and Dashboard applications, Persium provides the most comprehensive and accurate picture of the quality of air you breathe. 

Because everyone, regardless of their background, neighbourhood, nationality, or income, should have the right to breathe clean air. 

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