My colleague Doug Brugge offers a primer on what happens to people who live within 400 meters of major highways. To expand on this a bit, there are a whole lot of pollutants that come out of tailpipes but among the most important health hazards, now that we've put various kinds of emission control devices on cars, are so-called ultrafine particles (UFPs), which are less than 2.5 microns in diameter. That's really, really small. They are completely invisible, and odorless. You could breathe in millions of them with every breath and not know it.
They go right through the lungs into the blood stream and enter cells. They appear to cause generalized inflammatory responses, atherosclerosis, and to be acute triggers of heart attacks. As Doug tells us, the WHO says that something like 3.2 million deaths worldwide are caused by ambient particulate matter, and they're responsible for more lost years of life and healthy life than lots of risks we worry about more, including physical inactivity, high serum cholesterol, and occupational injuries.
But the risk is very localized. They're very highly concentrated close to major highways -- not so much urban arteries, which was counter-intuitive for me. But the point is the vehicles are going fast on the highway, so a lot more fuel is going through the engines than is the case in urban streets no matter how congested. But get 300 or 400 meters away from the interstate, and the level goes down to background.
About 4% of Americans live within 150 meters of a major highway, which is already bad news. I would very much want to be quite a bit farther away than that. So wanna guess who those folks are? This CDC report tells us. Anyway, you know the answer:
The greatest disparities were observed for race/ethnicity, nativity, and language spoken at home; the populations with the highest estimated percentage living within 150 meters of a major highway included members of racial and ethnic minority communities, foreign-born persons, and persons who speak a language other than English at home (Table). The estimated percentage of the population living within 150 meters of a major highway ranged from a low of 2.6% for American Indians/Alaska Natives and 3.1% for non-Hispanic whites to a high of 5.0% for Hispanics and 5.4% for Asians/Pacific Islanders. Likewise, the estimated proportion of the population living near a major highway was 5.1% for foreign-born persons, 5.1% for persons who speak Spanish at home, and 4.9% for persons who speak another non-English language at home.Poor people, immigrants. There are a whole lot of reasons why poor people are less healthy and don't live as long, and no it's not because they're irresponsible, lazy moochers. It's because their conditions of life are unfavorable. That's called injustice.