Air Pollution from automobile exhaust harms health
More science links pollution from tailpipes with ill health and death
As many others are, I’ve been overwhelmed with the news of the war in Ukraine. Each morning I scan the headlines, which tell me about the destruction, stupidity, and waste of the war.
The one direct effect of the war on things here in the United States, and elsewhere, is the jump in oil and gas prices. Politically, oil companies have their front groups like the Heritage Foundation, which have jumped on this price rise and are using it as an opportunity to cheerlead for looser regulations and giveaways for the oil corporations. Their friends in Congress, like Ted Cruz, are going to bat for them as well. Yet, as I mentioned in this publication earlier this month, there are some who see this as an opportunity to get more electric vehicles on the road.
Electric vehicles are seen as a way of reducing the amount of CO2 we pump into the air. They may also improve our health by eliminating car exhaust from highways and city streets. As the benefits of reducing air pollution—approximately 12 percent of all deaths worldwide in 2019 were caused by indoor and outdoor air pollution, ranking fourth among risk factors (behind hypertension, smoking, and bad diets)—seem so ever clear, it’s a wonder why reducing this pollution is not a priority.
Occasionally checking the air quality of where I live can be reassuring. It is usually ranked as “Good” or better, although it sometimes can be a mystery when I see that, only a few miles away, the map indicates that the air quality is moderate or poor. Are those folks driving their cars like crazy? Are they setting bonfires and throwing in all their plastic waste?
The most disconcerting experience of air pollution are the occasional days when the winds blow from the north, bringing all the pollution and smog from Los Angeles down our way. On those days, looking out over the ocean, I see a huge brown cloud looming over the waters of the Pacific. As it looks like it is hovering over the water and not close to shore, it’s easy to pretend that the dirt and toxins of the cloud are far away, but I know that I’m breathing in that dirty air.
Recent science
In a paper published in Particle and Fibre Toxicology in February scientists describe their finding that exposure to particulate matter from diesel exhaust messes up the microbial organisms in one’s gut. Our bellies are a menagerie of microbes, most of which are acquired in infancy. It has been found that not only are these bacteria essential for proper digestion, they play a part in our respiratory and circulatory functions, our ability to regulate weight, and even play a part on our emotional health. There are five different types of gut microbes firmicutes, bacteroidetes, actinobacteria, proteobacteria and verrucomicrobia. Each is important in its own way.
The scientists in this study exposed mice to diesel exhaust for 30 days. In experiments of this kind, diesel exhaust is used as a catch-all for traffic related air pollution. After a month of inhaling diesel fumes, the microbes in the guts of the mice were messed up. The mice had fewer actinobacteria, which are useful in maintaining homeostasis, the ability of the body to keep itself in a steady state. Messing up these microbes has been associated with cardiovascular disease in humans.
More science findings between air pollution and health problems
In another paper, researchers looked at and summarized the findings of other controlled experiments using diesel fumes. In all these studies the research subjects were humans, not mice. The paper was also published in the journal Particle and Fibre Toxicology in February.
Several of the studies found an increase in what is called oxidative stress, which is damage to tissue on a cellular level. Exposure to particulate matter from vehicle exhaust causes cells to release free radicals and peroxides. These can damage lipids, proteins, and even DNA. The list of maladies caused by oxidative stress is long and includes ADHD, cancer, heart failure, presenile dementia, chronic fatigue syndrome, and depression.
Some studies showed a link between diesel fumes and pulmonary inflammation and cardiovascular disfunction (rheumatic heart disease, angina, stroke, etc.). Other studies showed air pollution bringing about an increase in blood pressure and an impairment of cognitive functioning.
Particulate matter from diesel exhaust also exacerbated symptoms for asthmatics. If you are allergic to anything, dust, pollen, etc., air pollution will worsen your symptoms. And if you get the flu, being in an environment that has polluted air will make your coughing and sneezing worse.
It’s decades too late for me to use this as an excuse for my poor schoolwork, but people who have been exposed to air pollution over a long period of time—months or years—don’t perform as well on tests for verbal and math skills as folks who have not had similar exposure. Scientists and others fear that children are particularly susceptible to this adverse effect on cognitive ability. Tests on teens show that air pollution adversely affects their neurobehavioral functions.
Reducing CO2 emissions and reducing global heating aside, it seems ever so clear that moving away from oil as the fuel for our cars and trucks would be a great boon for our health. Knowing this, how can we continue to give our support to the oil companies?
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