Reducing pollution intake while walking or cycling

We don’t often think about how pollutants directly affect our own health, outside of issues like lead poisoning, radioactive leaks, or Beijing smog. However, there are much more subtle everyday health risks associated with pollution, especially air pollution created by traffic.

As cities and their populations continue to grow, and as people increasingly turn to walking or cycling for transportation or for recreation, they are being increasingly exposed to toxic chemicals produced by cars and buses.

But luckily for us city dwellers, Alex Bigazzi at the University of British Columbia has figured out the optimal speeds for cyclists and walkers to move along busy city streets in order to minimize the amount of pollution they breathe in.

“The faster you move, the harder you breathe and the more pollution you could potentially inhale, but you also are exposed to traffic for a shorter period of time. This analysis shows where the sweet spot is,” Bigazzi says.

The key is to walk or cycle at certain speeds, to achieve what Bigazzi calls minimum-dose speeds.

“If you move at much faster speeds than the MDS—say, cycling around 10 kilometers (6 miles per hour) faster than the optimal range—your inhalation of air pollution is significantly higher,” says Bigazzi.

The speeds in question vary by age and sex but luckily, they align pretty well with the speeds people normally move. While your speed might need to be modified a bit, you’re probably doing it right already.

Research like this is useful because it drives home the human cost of pollution, something that gets people paying a little more attention, on average, than the sufferings of animals they don’t see on a daily basis.

While this study does help people mitigate the effects of pollution, it also helps to illustrate how much we need to work on alternative energy in order to make our cities less polluted in the first place.