When people talk about the harmful effects of smoking, most of the attention is on the smoke itself. But everything that produces smoke also produces carbon monoxide, a chemical that, it turns out, may be more immediately dangerous than anything else in tobacco smoke. Carbon monoxide (chemical symbol CO) displaces oxygen in the body, and if enough of it builds up, it can cause the brain to shut down.
The carbon monoxide produced by smoldering tobacco is easy enough to measure, but how much of that actually makes its way into a smoker’s bloodstream? Previously, scientists had merely guessed about this, but new research has measured it by measuring the carbon monoxide in the air a person exhales 30 minutes after smoking. The researchers found that smokers acquire harmful levels of carbon monoxide from all forms of tobacco. The effective carbon monoxide levels are several times higher than was previously supposed.
The greatest danger was found in the recent fad of shisha, or fruit-scented tobacco smoked in a water pipe, usually known in the United States as a hookah. This was found to provide enough carbon monoxide to kill a person. These results startled everyone, including the researchers and the smokers involved. In most smokers, shisha-produced carbon monoxide displaced 8 to 12 percent of oxygen in the smoker’s bloodstream. These are levels somewhat higher than those of cigarette chain-smokers. But the amount of carbon monoxide produced in a pipe depends on the technique and the tobacco, and some smokers generated 10 times as much. (Burning fresh tobacco and inhaling very slowly would probably maximize the carbon monoxide levels, but this has not been tested.) Their blood carbon monoxide quickly passed the threshold level that medically is considered potentially fatal. In the worst cases, carbon monoxide built up to twice that level. There were no reports of actual deaths from this effect, but shisha carbon monoxide deaths surely must be occurring from time to time.
The thought of a few unfortunate people dying a quick death from tobacco smoke is troubling enough, but carbon monoxide affects anyone who breathes it in, and that means it affects everyone who smokes. By displacing oxygen, carbon monoxide reduces the energy available to every cell in the body, and this is especially evident in the brain. Carbon monoxide does not merely dull the brain and cause headaches and confusion, although that is bad enough. It creates a characteristic style of thinking. The carbon monoxide mind:
- Thinks paranoid thoughts
- Is especially suspicious of things near the edge of vision or hearing
- Magnifies things that are immediately present, and loses track of things that are not
- Has a diminished belief in time and change, so that it seems that the current experience is doomed to continue forever
The combination of suffering, confusion, paranoia, suspicion, loss of perspective, and hopelessness can be as dangerous as it sounds. People on carbon monoxide make bad decisions and are capable of extremely risky and harmful actions. It is easy to understand why carbon monoxide is associated with suicide. And now that we know how much carbon monoxide smokers inhale from cigarettes, it makes perfect sense that street criminals in literature are uniformly depicted as smokers. The high-risk, no-future thinking that it takes to be a street criminal is just like the kind of thinking produced by smoking tobacco.
It takes hours for carbon monoxide to work its way out of the body, so a person who smokes one pack of cigarettes per week or more has almost all of their thinking affected by carbon monoxide. Because of this, we can expect smokers to see things differently and behave differently.
Some of these differences could have economic significance. For example, we could predict that smokers may have lower saving rates. Part of the reason people save is because of a concern for the future, and carbon monoxide makes it harder to see into the future. It is a cliché that cigarette smokers worry more; perhaps this is reflected in economic behavior in a way that could be measured and verified.
We already knew that tobacco smoking was harmful, so the recommendation that smokers quit smoking is nothing new. Knowing a little more about tobacco’s immediate impact on brain function, by way of the carbon monoxide smokers take on, merely provides another reason to keep tobacco smoke out of your bloodstream.