What Analogies Can We Draw Between Air Pollution and Smoking?

Understanding Cigarette Smoke

When comparing cigarette smoking and air pollution, we must never underestimate the dangers that cigarette smoke poses to human health. There is no level of exposure to cigarette smoke that may be considered safe. The effects of cigarette smoking are not only felt by smokers but also by those around them, the so-called the “passive smokers”. Passive smoking includes inhaling second-hand smoke, which comes from a burning cigarette and the smoke exhaled by the smoker, and absorbing third-hand smoke, which is the residue of second-hand smoke that builds up on indoor surfaces over time.

Cigarette smoke is a complex mixture of thousands of chemical compounds, many of which are also found in other sources of air pollution. Smoke is a product of combustion and contains gaseous chemicals, liquid aerosols, and particulate matter.

Carbon monoxide, formaldehyde, benzene, hydrogen cyanide, nitrous oxides, and polycyclic aromatic hydrocarbons are just a few of the harmful substances found in cigarette smoke. These substances can lead to multiple and varied adverse human health effects, such as cancer, lung disease, heart disease, stroke, and reduced fertility.

Hazardous Components of Cigarette Smoke

Hundreds of the chemicals in cigarette smoke are toxic, and over 70 are known to be carcinogenic. Any substance that can cause or aggravate cancer is referred to as a carcinogen . These include: –

• 1,3-butadiene which is the most significant cancer risk in cigarette smoke.
• Polycyclic Aromatic Hydrocarbons (PAHs) which are a class of compounds known for their carcinogenic and mutagenic properties and more than five hundred different PAHs have been identified in tobacco smoke .
• Acrolein and acetaldehyde are some of the chemicals with the greatest potential to irritate the respiratory tract.
• Cyanide, arsenic, and cresols which have the most significant potential to harm cardiovascular health.

Cigarette smoke also contains carbon monoxide (CO). CO drastically reduces the amount of oxygen carried in the blood. The blood’s ability to carry oxygen is significantly reduced by CO. As a result, the heart must work harder, and the body’s organs receive less oxygen than they require, which increases the risk of heart disease and stroke.

Understanding Air Pollution

New research from Harvard University estimated that air pollution from fossil fuel emissions caused over 8.5 million deaths in 2018 for the first time surpassing the WHO’s annual estimates of 8 million premature deaths due to tobacco.

The term air pollution is used to describe anything that can affect indoor or outdoor air quality. Smog that pollutes the air in our urban environments can contain many of the chemicals found in cigarette smoke, it also contains additional pollutants that lead to additional potentially adverse health complications. Vehicle exhaust fumes, biomass burning , manufacturing and milling emissions and their associated downstream activities, and cigarette smoke all add to this pollution.

Several chemicals and by-products are created during these process that adversely effect on the health of exposed populations. These include particulate matter, polycyclic aromatic hydrocarbons (PAHs), carbon monoxide, aldehydes, organic acids, volatile organic compounds, nitrogen, sulphur, ozone, and inorganic substances.

Hazardous Components of Air Pollution

Tiny airborne particles, also known as Particulate Matter (PM), pose a serious threat to air quality. PM is often too small to be seen with the human eye. PM10 consists of coarse particles smaller than 10 microns, while PM2.5 are fine particles smaller than 2.5 microns. The average human hair is about 70 microns in diameter, making it 30 times larger than the largest speck of PM2.5. PM can consist of a wide range of solids and liquids, including metals, organic compounds, biological material, carbon, sulphates, nitrates, and other minerals. PM2.5 particles are considered the most dangerous type of pollution because they are small enough to get deep into the lungs when inhaled. Some can then enter the bloodstream, where they could spread to various organs.

Volatile Organic Compounds (VOCs) are sometimes referred to as hydrocarbons, this group of gaseous pollutants include a wide variety of different chemicals. VOCs can be naturally occurring or man-made. Common outdoor VOCs include emissions from oil and gas industry and vehicle exhaust. VOCs are also found indoors, contained in emissions from common household items such as manufactured furniture, fabrics, cleaning supplies, paint, and even building materials.

Sulphur dioxide (SO2) is created by the burning of fossil fuels, particularly by power plants and other industrial facilities. Ships, trains, and other vehicles can also emit SO2 if they burn fuel with a high sulphur content.

Carbon monoxide (CO) is a by-product of combustion and is released when something is burnt. Sources of CO include vehicle emissions, liquid fuel stoves, and other activities that burn fossil fuels. CO gas is both colourless and odourless and can be harmful if inhaled.

Nitrogen Dioxide (NO2) is a highly reactive gas produced when fossil fuels are burnt. The main sources of NO2 pollution include emissions from cars, buses, trucks, power plants and biomass burning. NO2 can also react with other airborne chemicals to produce both PM and Ozone.

Ozone (O3) occurs naturally in the stratosphere but can also be formed at ground level through reactions between different types of chemicals, such as organic compounds and nitrogen oxides. Once created, ozone can interact with other airborne pollutants to produce even more air pollution.

Are These Heath Risks Avoidable and Reversable?

Cigarette smoking was linked to lung cancer in 1964, and anti-smoking campaigns began in 1967. These campaigns have had a positive impact on public health in the United States, with smoking prevalence in male decreasing from 51.1% to 21.6% in 2010, and prevalence in women diminishing from 33.3% to 16.5% in the same period .

Air pollution is a global environmental health risk that affects populations in developed and developing countries alike, with 99% of the world’s population consistently exposed to air pollution levels that exceed the guidelines set by the World Health Organization (WHO) (Annual mean values of 15 μg/m3 for PM10 and 5 μg /m3 for PM2.5) .

Research shows that up to 90% of cancer cases are caused by environmental or lifestyle factors and that more than 90% of lung cancer deaths are caused by smoking and smog .

It can be argued that the ongoing indiscriminate industrial and agricultural practices that pollute the air and prioritise profit over people and the environment represent an assault on the environment and the people’s constitutional rights. These practices are unsustainable and need to be phased out before they have further negative consequences on human health.

While smoking causes disability and premature death are entirely preventable, the hazardous health effects of air pollution will not be avoidable for billions of people in the near future.

A recent study shows that the benefits of having clean air policies are even larger than previously calculated, as the findings suggest that long-term exposure to air pollution is damaging human health and especially to lung health. If the long-term cumulative effects of air pollution were to be included in policymakers’ cost-benefit calculations, the benefits of clean air outweigh the cost not properly addressing indiscriminate industrial and agricultural polluting practices .

Society must act now if it is to reverse the current and future adverse health effects of air pollution.