Oxygen is the third most abundant element in the universe and makes up nearly 21% of the earth's atmosphere. Oxygen accounts for nearly half of the mass of the earth's crust, two thirds of the mass of the human body and nine tenths of the mass of water. Large amounts of oxygen can be extracted from liquefied air through a process known as fractional distillation. Oxygen can also be produced through the electrolysis of water or by heating potassium chlorate (KClO3). Oxygen is a highly reactive element and is capable of combining with most other elements. It is required by most living organisms and for most forms of combustion. Impurities in molten pig iron are burned away with streams of high pressure oxygen to produce steel. Oxygen can also be combined with acetylene (C2H2) to produce an extremely hot flame used for welding. Liquid oxygen, when combined with liquid hydrogen, makes an excellent rocket fuel. Ozone (O3) forms a thin, protective layer around the earth that shields the surface from the sun's ultraviolet radiation. Oxygen is also a component of hundreds of thousands of organic compounds, according to the Jefferson Lab.

But more importantly, oxygen sustains life. Without a doubt, oxygen is the most essential element for all existence, according to the Global Healing Center. Through normal oxidation (the chemical union of an element with oxygen, such as what occurs during digestion, burning, or rusting), the universe regenerates by breaking down and reconstructing itself over and over infinitely. The life-enhancing element O2 (two atoms of oxygen joined as one molecule) is a critical component of the air you breathe. It is the element that sustains you. It is what you use to digest food and to break down toxins in your bodies so that they can be removed. Sometimes these things don't work so well.

•Pollutants in the air that you breathe, especially from your internal environments, reduce the level of oxygen available to you.
•Infirmities in our bodies can make it difficult to breathe at all, and can make it difficult to fully use the oxygen that you breathe in.

Oxygen bars have become increasingly popular among urban hipsters, and new bars keep popping up all over major cities, according to AskMen.com. Claiming to energize, relax and invigorate, these bars have fiercely loyal customers and are pulling in a fortune. But is paying for oxygen a breath of fresh air or just a load of hot air? Customers have the option of breathing unscented oxygen or choosing from a variety of fragrances. A session usually lasts from five to 20 minutes, and costs about $1 per minute. A regular user may come to a bar up to three times a week. Some oxygen bars offer other services, such as massages, health food and energy drinks. Most oxygen bars use a concentrator machine that filters out nitrogen and other atmospheric gases to produce oxygen that is about 95% pure.

Oxygen bar proponents claim that purified oxygen produces a blitz of health benefits, including:

--Reduced stress
--Increased energy
--Increased alertness
--Alleviation of the symptoms of hangovers, headaches and sinus problems.

While some people claim to feel long-term effects, others report feeling no difference. Some say it helps them sleep better and wake up with more drive. Bar owners also say their usual clientele includes marathon runners, students (before big tests) and older couples (before having sex). However, scientific data says that purified oxygen does very little, as our blood is already saturated with 99% oxygen. Any effect that may occur would dissipate within a few minutes, as the blood re-circulates. Although oxygen bars offer a respite from the many air pollutants found in large cities, many believe that it's the same as stepping into any building or car with an air filtration system.

Dr. Ron Balkissoon, a pulmonologist at the National Jewish Medical and Research Center in Denver, says that excess oxygen can increase the production of free radicals, those pesky overactive molecules that can greatly damage tissue over time. If you know your nutrition, you should eat lots of antioxidants to prevent free radicals. Balkissoon also says that too much oxygen can cause pulmonary edema, or fluid in the lungs.

Scented oxygen can also be dangerous, especially if the fragrance is oil-based. Dr. Norman Edelman, consultant for scientific affairs with the American Lung Association, says that tiny droplets of oil can accumulate in the lungs, and result in a kind of pneumonia called lipoid pneumonia. If that's not enough, excessive oxygen can be harmful for people with respiratory problems like emphysema. Those with medical conditions requiring oxygen should have it dispensed by a doctor.

According to Discovery Fit & Health, the average adult at rest inhales and exhales something like 7 or 8 liters (about one-fourth of a cubic foot) of air per minute. That totals something like 11,000 liters of air (388 cubic feet) in a day. The air that is inhaled is about 20-percent oxygen, and the air that is exhaled is about 15-percent oxygen, so about 5-percent of the volume of air is consumed in each breath and converted to carbon dioxide. Therefore, a human being uses about 550 liters of pure oxygen (19 cubic feet) per day. A person who is exercising obviously uses a lot more oxygen than that.

Some patients under certain types of heath care regimens use oxygen therapy, which can be self administered at home, according to Health Day News. If you're using at-home oxygen therapy, remember that you'll need to be very cautious around anything that has a flame or can ignite. The ADAM Encyclopedia offers these safety suggestions:
--Make sure there are working smoke detectors throughout your home, and keep a fire extinguisher handy.
--Never smoke or allow smoking around the oxygen; stay a minimum of 6 feet from any smoker.
--Keep the oxygen at least 6 feet from any fireplace, stove or electric appliance such as a hairdryer, electric toothbrush or razor, electric blanket, electric toy, space heater or electric baseboard heater.
--Keep the oxygen as far away as possible from an oven or stove while cooking, and be very wary of grease splatters.
--Keep the oxygen away from any flammable liquid.

Oxygen is critical to sustain life. Without it, cells in the human body begin to atrophy and die. You can only survive a few minutes without oxygen, but too much of it is also dangerous. Your body was made to consume just the right amount, but sometimes that perfect level changes due to illness or other stressors in your body. If you have health care challenges that are causing difficulty in breathing or other medical problems, see your doctor to find out what is causing the problem. Oxygen is one luxury you cannot afford to lose.

Until next time.