Heart Disease, Traffic Jams and ADHD Share One Simple Solution: Drive Less

This is an excerpt from “Bikenomics: How Bicycling Can Save the Economy,” by Elly Blue (Microcosm Publishing, December 1, 2013, bikenomics.com). See our interview with Elly from spring 2013. 

Car exhaust is no laughing matter. Nearly half of residents in major urban areas in North America live close enough to highways and other large roads to experience serious problems as a result. Exposure to car emissions worsens and may cause asthma and other lung conditions, including lung cancer. There is evidence to suggest that it leads to hardening of the arteries and thence to heart disease. One study has found an increased risk of heart attacks while in traffic, either while driving or using public transportation. Breathing car exhaust may increase the risk of developing diabetes; it is certain, however, that people who have diabetes suffer disproportionately from the effects of air pollution.

Traffic flows and air quality improved with the odd-even license plate restriction in Beijing during the Olympics. Photo: ##http://www.traffictechnologytoday.com/news.php?NewsID=7991##Traffic Technology Today##

The worst effects of breathing polluted air are experienced where it is densest: in traffic. Spending time on and near highways, freeways, and other busy roads is terrible for your health. How near is a question that is still being studied, but researchers believe that the effects are worst within either a fifth or a third of a mile. People in cars or buses are exposed to considerably more air pollution, perhaps because of, rather than despite, being in a closed space. People walking and bicycling on or next to roads breathe more air, but inhale somewhat less pollution; and cyclists have been found to have even less risk if they are on paths that are separated from the road.

The burdens that come with air pollution are, as with so much else, not evenly distributed. Poverty and ethnicity are both major factors that determine the amount of car exhaust we breathe. Housing near a source of pollution, such as a freeway, busy road, or industrial site is generally where people with low incomes are able to live.

Children are particularly at risk, beginning before birth. Air pollution affects prenatal development, and a recent study suggests that exposure to air pollution such as diesel particulates, mercury, and lead may put a child at risk for autism. A separate study found double the rate of autism among children who live within 1,000 feet of a freeway in several major cities. Air pollution has also been linked, tentatively, to hyperactivity in kids and childhood cancers. And kids who have high daily exposure to car exhaust score lower on intelligence tests and have more depression, anxiety, and attention problems. This isn’t just a matter of where children live — one in three public schools in the U.S. are within a quarter mile of a highway, well within the danger zone.

Traffic jams and air pollution are often talked about at once, as though one inevitably causes the other, and that by fixing one you can also solve the other.

It doesn’t quite work that way.

When a road has heavy traffic, more pollution hovers around it. We tackle this problem in every way possible from the supply side, with regulations on tailpipe technology, subsidies for hybrid and electric cars. And we try to solve pollution in the same way we deal with congestion — by building bigger roads. The current federal transportation bill explicitly offers clean air funds to pay for road widening projects that can show reduced congestion — no matter how faulty the long-term assumptions.

But even the short-term congestion relief — a few minutes each day — doesn’t fix pollution. When people can drive faster, they drive farther. Induced demand means that if a road does its job as a development tool, the long term impact of pollution — both on that road and on surface streets that it feeds into — goes up astronomically. These short-term reprieves amount to expensive long-term investments in much greater air quality problems, as the freeway projects of the past have demonstrated.

Also, slow traffic doesn’t necessarily mean more pollution. Hyper-milers — people who compete to eke the best gas mileage possible out of their cars — know this well. You burn the least fuel, and thus pollute the least, when you drive at a slow speed, providing a steady flow of gas to the engine or, even better, coasting. The biggest cause of pollution is the traffic dance of constantly speeding up, slowing down, braking, and idling. In urban areas particularly, the faster the speed limit or the feel of the street, the more starting and stopping drivers do. When traffic speeds slow down overall, the flow becomes smoother, and the result is less pollution. Lower speed limits have also been found to reduce emissions at highway speeds.

The best scenario of all when it comes to air pollution has nothing to do with tailpipe filters or hybrid, electric, or zero emissions car technology. The way to reduce pollution is to reduce driving, plain and simple.

The best proof of this comes during the Olympics. Athletes, like the rest of us, can’t do their work well while breathing bad air, but unlike the rest of us their needs are seen as an urgent reason to reduce emissions. During the 1996 games in Atlanta, car travel restrictions resulted in 23 percent less morning traffic. During that time period, ozone concentrations decreased by 28 percent, and emergency care visits for asthma went down by 41 percent.  A study of Beijing residents before, during, and after their 2008 Olympics found that their heart health improved significantly during the traffic and industrial restrictions that were part of the $17 billion campaign to clean up the city’s air — but risk factors went right back up after the restrictions ended.

The solution to both traffic congestion frustrations and the urgent public health crisis of air pollution is painfully obvious: We have to stop driving. Far from being an impossibility or a dreadful hardship, dramatically reducing the amount we drive is one of the easiest and most cost-effective measures we can take.

15 thoughts on Heart Disease, Traffic Jams and ADHD Share One Simple Solution: Drive Less

  1. Reason #1 that Mayor Lee should find a different location away from the already traffic gridlocked Bay Bridge area to build his legacy arena.

  2. “a recent study suggests that exposure to air pollution such as diesel particulates, mercury, and lead”

    No, it doesn’t. You didn’t even fact check with your link. The study looked at:


    particulate matter

    nitric oxide and

    nitrogen dioxide

    “A separate study found double the rate of autism among children who live within 1,000 feet of a freeway in several major cities”

    Here’s where you likely found that statement: http://www.sharedsolution.org/health-hazards/

    Here’s the link to the study cited for that proposition:


    It doesn’t say *anything* of the sort. (It would appear that someone misread “95% CI” to mean “95% increase”, which it doesn’t)

    ” one in three public schools in the U.S. are within a quarter mile of a highway, well within the danger zone.”

    The prior citations *all* note that freeways are being studied. This link notes proximity to “interstate, U.S. highway or state highway”–which includes a huge number of ‘city streets’–albeit 4 or more lanes, but roads *plainly* outside the research presented.

  3. Meanwhile, in the rest of the world…

    I note that the City of Toronto’s Public Health Department, headed by Toronto’s Medical Officer of Health, Dr. David McKeown, has issued a report on the effects of car drivers poisoning the citizens of that city. By way of their lethal poisons, just in the City of Toronto alone:

    Car drivers poison and kill 440 people every year.

    Car drivers poison and injure 1,700 people every year so seriously that they have to be hospitalized.

    Children and the elderly are most vulnerable to being poisoned by car drivers. In particular, children in Toronto experience 1,200 acute bronchitis episodes every year because they were poisoned by car drivers.

    Also, children in Toronto experience 68,000 asthma symptom days every year because they were poisoned by car drivers.

    The health costs due to people being poisoned by car drivers is about $2.2 billion in Toronto every year.

    Full details may be found on the official City of Toronto website at:


    My question is this: Where is the corresponding document for the City of New York? Are these inconvenient truths that the government just doesn’t want to know about?

    It is fairly easy to apply the same methodology to New York City. Even if one simply linearly scales for the population, that would give a fairly good set of results for the deaths and injuries due to people in New York being poisoned by car drivers.

  4. It’s not just the people who actually get sick enough to require medical intervention but also the fact that auto exhaust lessens the quality of life for everyone. It makes structures dirty and causes them to deteriorate. It makes going outside unpleasant or even unbearable. It has the effect of making some people, like me, nauseous when exposed to it. These things undoubtedly have a huge economic cost attached to them.

    I too would love to see a similar report for NYC. For me personally, auto exhaust makes going outside before about 8 PM difficult or impossible for the warmest 5 or 6 months of the year. This is despite the supposedly “cleaner” modern cars. No matter how clean cars are, until a few years ago SUVs didn’t have exhaust standards, and they comprised a rather large percentage of vehicles. Also, clean or not, when you have more vehicles the air will smell bad. I recall the air starting to smell better by the mid or late 1980s as cars got smaller and exhaust standards kicked in. And then in the early 1990s when SUVs took over the air smelled as bad as it did in the 1960s, if not worse.

    The inconvenient truth here is that in places like NYC the best off 1% or 10% likes to get around by car regardless of the negative effects of that on everyone else. In a true democracy they would be restricted from doing so to protect the non-driving supermajority. Unfortunately, we really live in a society of one dollar, one vote, not one person, one vote.

  5. The real disgusting perversion of our electoral system is the use of driver’s licences to register people to vote. Car drivers get to register to vote in a way that is fast, easy and convenient. However, if us peasants try to register to vote, we get hassled.

  6. Thanks for this important blog, Elly, that shows just how ‘toxic’ our roads, meaning the motor vehicles that they are built for, are to society – that’s all of us, but particularly those who live near them – usually the poorest among us. However, it should be pointed out that “driving less” is not the only solution. Driving ‘clean’, as in zero emission, is another alternative.

    Unfortunately, electric vehicles are very expensive – so there are ‘runner-up’ alternatives that include traditional, petroleum-consuming vehicles.

    The California Air Resources Board has a “drive clean” webpage that rates all vehicles.”>

  7. It would be even better if more people would drive vehicles appropriate for their uses. You don’t need an SUV at all unless you go regularly offroad or pull trailers. If you rarely drive with more than one person in the car, then a very small “neighborhood” type of vehicle, or even an electric bicycle, makes much more sense than a sedan. Too many people buy vehicles based on their worst case usage, not their daily usage. You can always rent a different vehicle for those times when your current vehicle is inadequate. People don’t buy moving vans in case they move. There’s no reason to buy vehicles based on what you might do with them twice a year. You increase your operating expenses the other 363 days. You also needlessly add to pollution.

    In my opinion, in urban areas we should pass laws mandating zero emissions vehicles only within, say, a decade. That will give people plenty of time to adjust by either buying a zero emission vehicle, or planning for a life in the city without a car.

  8. California has, in fact, passed a zero emission regulation that is clearly affecting the auto market, not just in California but throughout the U.S.

    From the governor’s “2013 ZEV Action Plan” [PDF]:

    “In March 2012, Governor Brown issued an executive order directing state government to help accelerate the market for zero-emission vehicles (ZEVs) in California. The Executive Order
    established several milestones on a path toward 1.5 million ZEVs in California by the year 2025….”

    To read how it’s affecting the market, see Planetizen, May 2013: Electric Vehicles Are Money Losers, But That’s Expected

  9. Mr. Love, what state do you live in? Here is California, the DMV issues “Non-driver ID” cards, which can be used for identification at government agencies and financial institutions, can be shown to law-enforcement officers, and can probably be used for voter ID. And in the US, most “peasants” have pickup trucks.

  10. I think he lives in the state that contains Toronto. And it is an interesting bit of bias that he points out in our respective democracies — if you drive, you carry the idea necessary to register to vote, fly commercial airlines, etc. Imagine the reaction if we declared that a driver’s license was only adequate as ID for driving purposes; that you needed a separate ID for everything else.

  11. Unless there’s been major corrections applied to the article above since your criticism, I think you’re picking nits. The link you mention:



    “Adjusting for sociodemographic factors and maternal smoking, maternal residence at the time of delivery was more likely be near a freeway (? 309 m) for cases than for controls [odds ratio (OR) = 1.86; 95% confidence interval (CI), 1.04–3.45]. Autism was also associated with residential proximity to a freeway during the third trimester (OR = 2.22; CI, 1.16–4.42). After adjustment for socioeconomic and sociodemographic characteristics, these associations were unchanged. Living near other major roads at birth was not associated with autism.”

    and in particular

    “We found little evidence of confounding by the socioeconomic and sociodemographic characteristics included in this analysis.”

    Their odds ratios are 1.86 and 2.22 — close enough to 2x for me — and they said freeway, and they said 309 meters, which is quite close to 1000 feet. They did not say “lead” or “mercury”, but their discussion of likely causes specifically mentioned automobile emissions, including particulate matter, polycyclic aromatic hydrocarbons, SO2, CO, O3, NO2.

    Their analysis seemed to point in the direction of particulate matter; they discussed the geographic distribution of PM around freeways, as well as some of the biological pathways through which it might cause damage. And yes, I see that they did not find a statistically significant correlation with proximity to “major roads”, but Elly Blue quoted their work accurately (at least, in the version of this article that I read). This apparently suggests PM as a cause, but you go into a study with the hypoheses that you start with, and if you discover suggestions of some better hypotheses after the fact, that has to be a new study.

    I checked your other criticisms, and I don’t think they rise above the level of nitpicking; if you track them down to research articles and academic websites, they seem to say what Elly Blue says they say.

  12. Reminds me of my first wife (divorced long ago). She had the attitude that anyone over 18 who didn’t drive was not “grown up” and would rather remain “dependent”. I think this is a common attitude among many Americans–“normal people” drive their own cars (and SUVS, minivans, etc.), while “losers” ride public transit and “long-haired hippie vegan types” ride bicycles. Not saying this is right, or “sustainable”, but it’s the vibe I get from folks outside the Streetsblog world.

  13. Hey, just noticed something else, and it *really* should be something you change: ADHD (in the headline) and Autism (in the article) are NOT the same thing. There is some overlap, but it’s more than even reductionist to equate them.

    Do recognize that the hed may have been written by someone other than the author.

  14. This actually makes sense as there is an upsurge of diseases that can be attributed to the pollution. However, there is no definite way of avoiding this trend and so many people continue getting caught up in it. intergratedmedicine.com

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