Air’s journey in quick-growing cities

Text and pictures by Kabisha Velauthapillai

Have you ever thought about the journey our air takes to eventually reach the depths of our lungs? From our lungs, the air goes on a fluid adventure through our blood, reaching our brain, our heart, and the tips of our toes. What about our air’s journey before we breathe it in? Where does it come from? A lot of research on environment and health is focused on this exactly: the journey of air pre-breath and the journey post-breath. We’re finding out just how complicated the air around us is. Our air is made of tiny particles. Some particles keep us healthy, while others contribute to bad health like heart and lung disease.

With air being everywhere, all around us, all the time, air pollution is hard to get away from. Air pollutants come from very different places. For instance, what’s the first thing you thought of when you read the words “air pollution”. For a lot of people, the first image they think of is the distant factory with a thick greyish smoke rising from it. Pollution from factories can seem hard to stop, but there’s another, more common, more immediate place that might be a bit easier for us to act on as average citizens. This ‘place’ is TRAFFIC.

Traffic on highway study city

A main highway passing from the North to the South of the city.

That’s right, the collective of vehicles we drive throughout the day, week, month, year all add up. Traffic ends up being a major source of air pollution in cities around the world. It’s especially a problem in cities growing at a very quick pace. The quick growth often means we don’t have enough time to plan for a city structure and city services that can accommodate a growing number of people. With more people, streets are more crowded and more vehicles are zooming, sometimes zig-zagging, from one place to another. In the Global South many are moving from rural areas to cities, searching for stable opportunities for their families and themselves. That’s why quick-growing cities with increasing traffic are particularly common in the Global South.

Research on traffic-related air pollution is abundant in the Global North, where there are more resources put toward these studies, but the research is greatly lacking in the Global South. You may be asking: “well, what’s wrong with applying traffic research from the Global North to cities in the Global South?” That’s a great question. The thing is, cities in the North have typically been around for much longer, meaning more preparation for growth. They also typically experience different environments compared to cities in the South. Remember when we were talking about the journey of air at the beginning? We’re bringing that right back here. The types and amounts of harmful tiny air particles can be different in Global South and Global North cities. They are often different between Global South cities too, because of climate types, altitude, types of economies, and a lot more. This is why it’s important to study the journey of air in different cities, especially when the information is not there.

Women walking in an alley

An alley in El Alto Viento: one of the study neighbourhoods.

Traffic-related air pollution in the Global South is a public health dilemma, calling policy makers and urban planners to the table. However, to get these stakeholders involved, we need well thought-out, properly designed research in epidemiology, which studies the health of populations. We need to research the types and amounts of harmful air pollutants and how they can affect people’s health. This was the goal of a pilot study conducted by the Baumgartner research group this summer. The interdisciplinary, multi-country team collected data in Bucaramanga, Colombia. Right now, we are analyzing the data, trying to better understand how air pollution might affect the health of people in Bucaramanga.

Scientific equipment

An outdoor roof kit set-up.

By figuring out the types and amounts of harmful tiny air particles and their impacts on health, we can better understand how the air we breathe can also negatively affect us. Many of us have families and roots in the Global South, making it all that much important to study the impacts of air pollutants on the health of people. It’s essential that such research takes place through South-North collaborations, supporting people who are already engaged in cities in the Global South. Maintaining a culture of solidarity with our partners in the South is key for working toward improved health of the global population.

In addition to these studies, it’s important to get the word out about traffic-related air pollution: what it is, how it affects our health, what people are doing about it, and what we CAN do about it. Each one of us have the right to know and to engage in this discussion on an issue that affects us all.

More about the author here.

Marching to a Different Beat: No Pulse, No Problem

Image from University Health Care System

By Amy McKean

We have seen it in countless movies and tv shows. The protagonist walks in and sees someone they care about lying down and unresponsive. This hero immediately rushes over to see if they are alive by checking for a pulse, but that may not be enough information anymore. Research into left ventricular assist devices (LVADs) have shown that we do not need a pulse to live.

Most of us have heard of pace makers, devices that can be used to aid or replace the electrical system in the heart. The electrical signal is responsible for causing muscle contractions that lead to the heart beating and the movement of blood throughout the arteries and veins of the circulatory system. Pace makers can be used when the only problem is with the electrical signal. With Heart Failure, the muscle of the heart is weak or damaged and therefore unable to sufficiently pump blood throughout the body. In this case, the problem requires more than an electrician; we need a plumber to work on the blood flow.

Many cases of Heart Failure do not require the replacement of an entire heart, but rather, the heart just needs some help. LVADs have been providing this assistance for a few decades now. They provide an alternative path for blood to travel and be pumped throughout the body. Initially these devices attempted to mimic the pumping action of the heart by using positive displacement pumps. This style of pump has a chamber that fills with liquid and is forced out by the chamber reducing in size. While these pumps worked to an extent, there were still problems such as size and reliability. A better pump required marching to a different beat.

Centrifugal and axial flow pumps are different than positive displacement pumps and work by the rotation of an impeller blade. The blood flowing through such a device will move continuously and not have the natural beat pattern observed in our heart. The full effects of removing an individuals pulse are still under investigation, but what is known is that these devices can be used to help prolong an individual’s lives successfully. If you come across someone alive, but without a pulse, they are probably not a zombie. They likely are closer to a cyborg, with a mechanical device operating in place of their heart.

More about the author

2 different types of LVAD (Rogers et al., 2017)

Blog authors are solely responsible for the content of the blogs listed in the directory. Neither the content of these blogs, nor the links to other web sites, are screened, approved, reviewed or endorsed by McGill University. The text and other material on these blogs are the opinion of the specific author and are not statements of advice, opinion, or information of McGill.