The term “air pollution” has become so ubiquitous that when anyone hears those words, they have an understanding of what they mean. To a degree, it is an accepted fact of the modern world that the air we breathe is contaminated in some way, but most people don’t realise the severity of the problem, the effects it can have on health, or the potential there is to combat the ongoing epidemic. In a series of articles, CleanTechnica will be examining the issues surrounding air pollution in more depth, and this first article will act as an introduction to some of the main issues.
In broad terms, air pollution is any gas or substance that is released into the earth’s atmosphere in large enough quantities to harm the health of humans or animals, negatively affect the growth of plants, damage the manmade and natural environment, or cause other problems such as bad odours or poor visibility. While air pollution can be the result of natural activities — for example, a volcanic eruption — human activity is the greatest modern cause of air pollution.
Air pollution is measured through a combination of monitoring stations and modeling. Modeling is the mathematical simulation of how air pollutants are dispersed in the atmosphere, whereas monitoring stations measure the concentration of pollutants in the air. The most commonly measured pollutants are ground-level ozone, nitrous oxide, sulfur dioxide, carbon monoxide, and particulate matter.
Ground-level ozone is created by chemical reactions between nitrous oxide and volatile organic compounds in the presence of sunlight. Breathing in ozone can cause a multitude of health problems, especially in parts of the population that are sensitive to lung problems, such as those with asthma, children, and the elderly.
Nitrous oxide is released into the atmosphere through the burning of fuel, mainly coming from the emissions of vehicles. It has serious environmental impact, forming acid rain and also impacting visibility.
Sulfur dioxide is also released into the atmosphere via the burning of fossil fuels, and short-term exposure to high levels can damage the respiratory system and may cause breathing difficulties.
A high level of carbon monoxide is most dangerous in an enclosed environment, but a high outdoor level can also be dangerous for those who suffer from heart disease. The greatest source of carbon monoxide is vehicle emissions.
For particulate matter, there are two common forms measured — PM2.5 and PM10. Both are a mixture of solid particles and liquid droplets, with PM10 being particles that are less than 10 microns and smaller, an PM2.5 being particles that are 2.5 microns and smaller. We’ll be looking at this measure in more depth.
The data provided by these methods make up an air quality index (AQI) that indicates the level of air pollution. AQIs vary from country to country on account of differing national air quality standards, but they all signal the health risks present according to the degree of pollution. The higher the AQI, the greater the likelihood of experiencing adverse health effects.
Looking Closer at the Air Quality Index
The air quality index is measured in real time for more than 70 countries in the world and displayed via aqicn.org. Here you can see current air quality and the health effects it might have for different cities and regions.
Particulate matter 2.5 is a key measure of air pollution. These particles are small enough to travel through a person’s respiratory tract into the lungs, resulting in all manner of health problems, such as lung cancer, chronic bronchitis, and heart disease. The particles themselves come from various sources, but the burning of fossil fuels to power vehicles is a key contributor. This makes PM2.5 a big issue for densely populated inner-city areas with large amounts of traffic, such as New York City. Two midtown NYC districts exceed the World Health Organisation (WHO) guidelines for acceptable levels of 12 micrograms per cubic metre. The city is currently addressing this and other related issues.
What is alarming is that when you look at the AQI and presence of PM2.5 for a city such as Beijing, the levels are frequently at a level high enough to cause health problems for everyone, with people who are sensitive to air quality – such as those with respiratory difficulties like asthma – being advised to avoid outdoor activities and exertion. In some locations in Beijing, the PM2.5 is as high as 172, which when compared to an average of 21 in Berlin shows just how serious this is.
7 Million Premature Deaths
The extent of the health problem posed by air pollution is vast. In terms of diseases, it contributes to heart disease, cancer, stroke, respiratory problems, and more. It’s an almost silent killer that one may barely notice, yet the impact that it has on mortality is devastating. In 2012, the World Health Organisation reported that an estimated 7 million people die prematurely each year as a result of the effects of air pollution. That’s a staggering 1 in 8 global deaths. By any definition, this represents a crisis.
When we move beyond the health costs and start to factor in the financial costs that air pollution inflicts on the world economy, concern only deepens. According to a joint study by the World Bank and the Institute for Health Metrics and Evaluation (IHME), the productivity losses and degraded quality of life due to air pollution costs the world economy $5 trillion per year.
Fossil Fuels Still #1 Cause
While it won’t be news to anyone that human beings are the greatest contributors to the air pollution epidemic, it is worth pressing the point home that the production of carbon dioxide through the burning of fossil fuels is still the single largest cause of air pollution. We are still dependent on fossil fuels for the production of energy and for almost all aspects of transportation. In the US, according to the Environmental Protection Agency, 30% of greenhouse gas emissions are due to electricity production, with transportation coming in as the second biggest contributor at 26%. Given that our need for energy and transportation is going to keep increasing rather than lessening, something needs to change.
The push towards clean, renewable energy sources and electric vehicles are significant steps, and the Paris agreement will play a big part in combatting the root cause of a lot of air pollution. There has also been a proliferation of technological advancements that have helped to reduce or remove contaminants from exhaust streams, and there are continual developments being made by forward-thinking startups determined to find ways to address the problem. This is a global crisis that needs a global solution.
At CleanTechnica, we will be looking in more depth at the challenges, solutions, and issues surrounding air pollution in future articles. If you have an idea of an area you think we should cover, get in touch.