Urine
Urine is a liquid waste product produced by the kidneys and expelled from the body through the bladder and urethra. Typically yellow in color, urine consists mostly of water along with various waste substances such as urea, inorganic salts, and creatinine. It plays a crucial role in the body's waste management, filtering out excess water, salts, and nitrogen compounds from the bloodstream. The characteristics of urine, including its color, pH, density, and odor, can provide valuable insights into an individual's health, with tests like urinalysis commonly used to detect issues such as infections or drug use.
Historically, urine has been used for various practical purposes, including laundry and even the production of gunpowder due to its nitrogen content. Notably, urine has also contributed to advancements in organic chemistry, with significant discoveries stemming from its study in the 18th and 19th centuries. Despite some misconceptions, urine is not sterile, and its composition can indicate various health conditions, such as dehydration or liver disorders. Understanding urine's functions and implications can deepen one's awareness of both personal health and historical practices.
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Urine
Urine is watery-like excrement, typically yellow in color, which comes out of the human body from the bladder through the urethra. It is made by the kidneys, travels through two tiny tubes called ureters, and is then stored in the bladder. A normal bladder can hold up to two cups of urine for two to five hours. Urine contains the body's extra water and salt and nitrogen compounds that are filtered by the blood and the kidneys. Much can be determined about a person's health by the color, pH (acidity), density, and odor of his or her urine. The frequency of a person's urination can also give health care providers insight into a person's health. Various tests can be run on a person's urine to determine illness or what is going on in the body. The most common test is a urinalysis, which analyzes urine based on its physical and chemical makeup. A urinalysis can determine different scenarios such as if a person has a urinary tract infection or if a person has been using drugs.
Urotherapy, or urine therapy, the practice of using one's own urine or another person's urine for medicinal or cosmetic purposes, is a topic that has long been debated in the medical community. Most health experts say that urine is not sterile and should not be drunk or applied to skin to bring about health.
Brief History
Throughout the course of history, urine has had many different uses. When urine sits for long periods, it decays into ammonia. Because of this feature, it was used to clean clothing and soften animal hides. The ancient Romans often collected urine in the streets, and it was taken to places where laundry was done and poured over dirty clothing. Early European people also used urine to get stains out of clothing.
Another popular use for urine used to be to make gunpowder. To make gunpowder, there are a few things needed: charcoal and sulfur in small quantities and potassium nitrate, which was not manufactured on a large-scale until the early twentieth century. Before it was available through mass production, gunpowder was manufactured with urine. Gunpowder makers used urine because of the nitrogen that is naturally found in it. To make potassium nitrate from urine, ammonia from stale urine is mixed with oxygen to form nitrates. These nitrates, which are negatively charged, bind with positively charged metal ions. The substance is filtered and is then considered potassium nitrate. This potassium nitrate was then used as a component to make gunpowder.
Organic chemistry also got its start with urine. In 1828, German chemist Friedrich Wöhler created a substance identical to the compound urea by mixing silver cyanate with ammonium chloride. Creating urea from scratch disproved a hypothesis that living organisms were made up of substances different from inanimate objects like rocks or glass. This discovery proved that organic chemicals could be produced in a lab and that humans were a part of nature, not separate from it. This began the field of organic chemistry.
Alchemists, or people who tried to turn metal and other things into gold, spent a lot of time trying to get gold from urine, but this led to other important discoveries. German alchemist Henning Brand discovered white phosphorus when he distilled fermented urine in 1969. French chemist Hilaire Rouelle discovered the organic compound urea when he boiled urine dry in 1773.
Overview
In the human body, urine begins forming in the nephrons of the kidneys by filtrating blood plasma into the nephrons. This fluid passes through the nephron tube, and the components of it that can be used by the body are reabsorbed into the blood stream. Some of those components include amino acids and glucose. The rest of the material is considered waste and is stored in the bladder until it is expelled through a process called urination. Most of this waste contains water, almost 95 percent of it, but the rest is made from urea, inorganic salts, creatinine, ammonia, and other materials. Urine is stored in the bladder until it is expelled through a process called urination. This liquid has a pale-yellow color because the material also has pigmented products of blood broken down in it.
Healthy urine should have a pale-yellow color, but the color of a person's urine can give health experts information about a patient's health. If a person's urine is dark yellow that can indicate that he or she is dehydrated and do not have enough water in the body. Sometimes the color of urine can change based on what types of food a person has consumed. Pink urine can be caused by eating beets and greenish urine can be caused by eating asparagus or foods with green dyes. Sometimes the color of urine can help health professionals diagnose diseases. When urine has blood in it, that can be a symptom of many different conditions. If urine is dark orange or a brown color, it could be a symptom of jaundice, which is a yellowing of the skin due to an increase of bilirubin in the body. Dark orange or brown urine could also be a symptom of Gilbert's syndrome, a genetic liver disorder that causes an increase in bilirubin in the body.
There is other information that is available to health care professionals based on the makeup of urine. The volume and color tell about hydration levels. Elevated white blood cells can indicate a person has a urinary tract infection.
Contrary to widespread belief, urine is not sterile. This myth has roots in the 1950s, when Edward Kass, an epidemiologist, was searching for ways to test patients for urinary tract infections before performing surgery on them. He created a urine test that obtained urine midstream, and set a numerical cut-off for the number of bacteria in healthy urine: not more than 100,000 colony-forming units per millimeter of urine. If the bacteria count was below this amount, the patient tested negative for bacteria in the urine. Then people began to believe that there were no bacteria in urine, not understanding that the number just needed to be below a certain threshold.
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