This morning I got stuck behind a bus during my bike commute. It felt like I was sucking air right out of the exhaust pipe. But this usually doesn't happen, because I have tactics I use to keep my lungs safe most of the time. If you ride your bike in a polluted urban environment like Los Angeles, there's really a lot you can do to minimize the smog you breathe in.
First, if you have the option, you can cut your exposure to pollution by 10-30% just by riding in off-peak hours. The best time is early in the morning, before rush hour. Next best would be midday, or late at night.
If you're not commuting by bike, and you just like to ride for the fun of it, be a weekend warrior. Ride your bike on the days when there are fewer cars on the road.
If you commute to work, and have to ride your bike during rush hour, you can save your lungs by taking alternate routes.
Almost every busy street has other streets running parallel to it, and the traffic on these other streets can be a lot lower. If you can get just 50 feet away from the heaviest traffic, you can make a dramatic cut in the amount of pollution you breathe in.
In fact, a Danish study found that when you bike on streets with low traffic volume, you can reduce your exposure to pollution by 50% to 60% or even more.
And when you think about it, you'll have a safer, more quiet ride. Also more scenic. You're more likely to pass parks and gardens. You won't have to worry as much about being hit.
If you commute by bike, there might be stretches where you have to be on the busiest roads, but probably not for the entire route. Anything you can do to reduce the time you spend riding in traffic will pay off.
There will be more stop signs, and you might add an extra 10 minutes onto your journey. But you could also add years to your life.