You also devote a lot of the book to industry efforts that try to discredit the science about tobacco, secondhand smoke, and fine particulate matter from energy sources—all in the name of protecting profits.
I think the starting point was the tobacco industry responding to the evidence about the harmful effects of smoking. It established a model and approach that was fairly sophisticated and moderately effective in pushing back the timeframe when public health and regulatory efforts could convince people that smoking was a bad idea. While industry may have delayed regulation and public awareness, it was not ultimately successful. In developed countries, smoking rates are way down, and secondhand smoke is less prevalent as smoking is usually pushed outside of buildings in countries like the U.
And fine PM are now regulated; even in counties like China, where fine PM is still very high, they are trying to reduce the levels.
As a society we need to be respectful of scientific evidence. There is a tendency in the media—and among the public and policymakers—to not understand how science works. But at any point in time you have to make some decisions with what evidence you have and implement the best policy and practice that is consistent with what you know at that time.
I try to keep an open mind, though, that the evidence can change. The EPA under the Trump administration is relaxing coal emission standards—what will be the impact? The Trump administration has been trying to set back standards to what they were before the Obama administration. In Britain, air pollution is second only to smoking as a health risk, causing as many as one fifth of all deaths in my adopted hometown. Across Europe, it kills more than 15 times as many people as car crashes. Nothing is as elemental, as essential to human life, as the air we breathe.
Yet around the world, in rich countries and poor ones, it is quietly poisoning us. Not far from where I grew up, and many years later, researchers took advantage of the natural experiment created when highways in New Jersey and Pennsylvania replaced the old-fashioned tollbooths where we used to hand cash to an attendant or toss coins into a basket with the high-tech kind that charge the fee electronically as you zoom past. The switchover dramatically reduced backups at the collection points, and the researchers found rates of premature birth dropped by about 9 percent for pregnant women within a mile and a quarter radius of where the old booths had been.
While that change was positive, it made clear the disturbing link between the highway exhaust so many of us breathe and a pregnancy outcome that can have lifelong consequences for babies born early.
None of us can. And that invisibility is a strange feature of this crisis. When smokers succumb, they know their own actions, and those of the tobacco companies that fed their habit, helped bring about their illness. But, in a world powered by fossil fuels, we all travel from place to place, use electricity, heat our homes, and few of us fully grasp the effects. The gains that come when air gets cleaner are similarly difficult to see. But those whose years are lengthened, and those who love them, never know it.
And why. Is air pollution an inevitable part of modern life, something we must resign ourselves to living with? Or are there more malign forces at work, too, keeping us wedded to the old, dirty ways of doing things when better alternatives exist?
And, most importantly, what would it look like to do things differently, to build a cleaner, healthier world? Mobile Newsletter banner close. Mobile Newsletter chat close. Mobile Newsletter chat dots. Mobile Newsletter chat avatar. Mobile Newsletter chat subscribe. Physical Science. Chemical Elements. Is it harmful to breathe percent oxygen? Just Breathe Now what would happen if you breathed percent oxygen? In humans breathing percent oxygen at normal pressure, here's what happens: Fluid accumulates in the lungs.
Gas flow across the alveoli slows down, meaning that the person has to breathe more to get enough oxygen. Chest pains occur during deep breathing. The total volume of exchangeable air in the lung decreases by 17 percent. This released CO2 increases the concentration of CO2 in a closed room. Other sources of CO2 in a room include smoking, cooking using a gas or wood stove, and using fireplaces. Any open flame in your home is creating CO2.
However, if you are in an area with exposure to fire or combustion, whether natural or man-made, CO2 levels in that area may become dangerously high. CO2 is not poisonous; as a gas, CO2 itself will not hurt you.
This is an important fact to remember, as carbon dioxide is a vital part of the environment. The human breathing mechanism actual revolves around CO2, not oxygen. Without carbon dioxide, humans wouldn't be able to breathe. Carbon dioxide acts as a simple asphyxiant; in other words, as CO2 levels in a closed room rise, carbon dioxide replaces the oxygen your body needs.
Because carbon dioxide is an asphyxiant, it mostly affects your brain. At moderate CO2 levels, around ppm, there are observable effects on your thinking. These same levels also reduce concentration and focus, as well as create discomfort from breathing stuffy air.
At higher levels, around ppm, there are significant reductions in cognitive functioning , especially for tasks that require higher-level thinking. People feel fatigued and report having more headaches. These conditions are less common but can still occur regularly in schools and poorly ventilated buildings.
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