For decades, the conversation over vehicular traffic and its affect on air quality, human health, and the environment has centered on engine emissions. It’s simple, really. The motor burns fossil fuels, and despite greatly improved systems in recent years, exhaust from that burning comes out the tailpipe and into the air. Government regulation and industry effort has been focused on reducing the amount of emissions from our cars for a long time.
Unfortunately, as I found out today, emissions from the engine are not the only danger to human respiratory health that come from our highways. A recent study published by the Georgia Institute of Technology shows that metals in the air from brakes and tires cause serious health issues, too.
Here’s the breakdown:
- Our vehicles emit metals such as as copper, iron, and manganese as we drive them.
- These metals interact with particles of sulfate already in the air to produce “a toxic aerosol.”
- The sulfate changes the solubility of the metal particles. This is key, since our cars emit the particles in a insoluble form. After spending time with sulfate, however, they become soluble. This means that the metal can go right into the bloodstream after being inhaled.
- Researchers used a test to determine the oxidative potential of the emissions and found that it was associated, statistically, with hospital admissions for asthma and wheezing.
Obviously, this all falls into the “not good, but glad to know” category. It means that low-emission vehicles, like electric cars, are still putting material in the air that can harm us. It means that if you live close to a major roadway, you might want to be concerned about what you’re breathing. The study collected data from two sites in Atlanta, one close to a roadway, and another 420 meters away. While it found fewer particles in the air that was farther away from the road, there was still enough to cause problems with your health.
All of this makes me rethink our relationship with cars. Improving technology has greatly reduced the amount of particulate matter our engines put into the air, but this study shows me that we have a long way to go in making our cars truly clean. Indeed, as a layman toward auto engineering, I wonder if metals coming from brakes and tires will ever be completely addressed. After all, these systems depend on friction, and that means they wear out. As your tires go from new to bald, that rubber has to go somewhere. The same is true for your brake pads. It turns out that the missing material from these items is in the air, and eventually, in our bloodstreams.
So where does that leave us with cars? Newer cars with lower fuel emissions would seem to be outputting the same amount of brake and tire particulate as older vehicles. I don’t have an answer, but I wonder if we eventually won’t drive cars, or at least view them as a personal necessity like we do now. Other forms of transportation may appear that lessen our collective impact on the environment and our health.
But that is many decades away. For now, the answer might be simply driving less. Combining multiple trips into one, carpooling, riding a bike, or even walking may be the best defense against adding to our already-dirty air.
Clean Air Clicks
- Dust from mining costs an Australian town $300 million
- Flecks of Extraterrestrial Dust, All Over the Roof. Not all of the dust around you is from your neighborhood. Interestingly, a Norwegian jazz musician spent eight years studying the subject, training himself to distinguish between dust particles from Earth and those from outer space.
- Best Dusting Tools for Spring Cleaning. The air you breathe inside your house is important. Consumer Report’s article will help you see what technique is best for what job.