How long can a human survive without water?
Hiking equipment
According to Tom Brown, the basic plan for survival is in the order of shelter (including clothing), water, fire, and food. Cody Lundin writes about the "Rule of 3s"; this relates to human survival without basics: three minutes without air, three hours without shelter, three days without water, or three weeks without food.
Yapunyah waterhole
Aquatic organisms which lack desiccation-resistant life-stages (i.e. cannot survive ‘drying out’), are reliant on refuges during drought, as are wetland-dependent organisms which do not readily disperse, or which cannot move long distances between isolated habitats. Such animals include all fish, some macroinvertebrates, the Cooper Creek Turtle "Emydura macquarii emmotti" and water rat "Hydromys chrysogaster".
Henry S. Tanner (doctor)
Because no one believed his claim that he had fasted for 42 days, in January 1880, Tanner, a practitioner of hygienic medicine, announced that he would repeat his experiment to show that humans can survive without food and would agree to submit himself to be placed “under the care of any medical society” that would provide adequate housing. On June 30, Tanner began his attempt to duplicate his 40-day fast and after the 6th day, the New York Times began a series of articles chronicling his day –to-day progress, each dispatch becoming more ominous in its anticipation that his death by starvation was imminent. As the twelfth night approached, a Times headline announced that “The End [was] Predicted to be at Hand”. But rather than deteriorating, by the twentieth day, Tanner’s condition improved and he “looked and acted better than ever”.
Water scarcity
Water scarcity is the lack of fresh water resources to meet water demand. It affects every continent and was listed in 2015 by the World Economic Forum as the largest global risk in terms of potential impact over the next decade. It is manifested by partial or no satisfaction of expressed demand, economic competition for water quantity or quality, disputes between users, irreversible depletion of groundwater, and negative impacts on the environment. One-third of the global population (2 billion people) live under conditions of severe water scarcity at least 1 month of the year. Half a billion people in the world face severe water scarcity all year round. Half of the world’s largest cities experience water scarcity.
Jesse Mugambi
Mugambi emphasizes that our survival as human beings across generations will depend on how we manage our ecology – the flora and fauna in all the habitats where human beings have their abode. The availability of fresh water determines the habitability of an environment. Most of the land on the continent of Africa has arable soils, but freshwater is very unevenly distributed. Fresh water can be obtained from rivers, fresh-water lakes and underground aquifers. The most cost-effective source of fresh water is rainwater harvesting. In his book Fresh Water to Eradicate Poverty he observes that Africa has the largest quantity of stable rainwater runoff, which may be harvested season after season, accumulating huge quantities to be used for agricultural, domestic and industrial applications. Rainwater harvesting can also help to recharge the rivers, lakes and underground aquifers. As a practicing ecologist, Professor Mugambi is a trustee of the Kenya Rainwater Association and the Utooni Development organization. He is also a member of the Ecumenical Water Network and the World Council of Churches Working Group on Climate Change. As a result of Global Warming there are unpredictable extremes every season in all regions, making survival difficult for communities that depend on seasonal rains for agriculture and staple food. The droughts are longer and more severe. The rains when they come are heavier and for shorter periods, making it difficult for crops to grow to maturity. The regularity of the seasons can no longer be taken for granted. Rehabilitation of local environments is a necessity rather than a luxury for all regions. Jesse Mugambi has worked with communities in various African countries to promote awareness about the global ecological crisis.
Bigu (grain avoidance)
Ge Hong chronicles the effects of grain avoidance. 
I have personally observed for two or three years men, who were foregoing starches, and in general their bodies were slight and their complexions good. They could withstand wind, cold, heat, or dampness, but there was not a fat one among them. I admit that I have not yet met any who had not eaten starches in several decades, but if some people cut off from starches for only a couple of weeks die while these others look as well as they do after years, why should we doubt that the (deliberate) fasting could be prolonged still further? If those cut off from starches grow progressively weaker to death, one would normally fear that such a diet simply cannot be prolonged, but inquiry of those pursuing this practice reveals that at first all of them notice a lessening of strength, but that later they gradually get stronger month by month and year by year. Thus, there is no impediment to the possibility of prolongation. All those who have found the divine process for attaining Fullness of Life succeeded by taking medicines and swallowing breath; on this they are all in perfect agreement. A moment of crisis, however, generally occurs at an early stage when medicines are being taken and starches abandoned and it is only after forty days of progressive weakening, as one uses only holy water and feeds solely on breath, that one regains strength. (15, tr. Ware 1966:246-7) 
This "holy water" refers to a Daoist "fu" 符 "talisman" dissolved in water. Ge Hong further cites an Eastern Wu historical example to show that drinking holy water cannot prevent death. When Emperor Jing of Wu (r. 258-264) heard about Shi Chun 石春, a Daoist healer "who would not eat in order to hasten the cure when he was treating a sick person," he exclaimed, 
"In a short time this man is going to starve to death." Then he had him locked up and guarded, and all that Shih Ch'un requested was two or three quarts of water for making holy water. It went on like this for more than a year, while his complexion became ever fresher and his strength remained normal. The emperor then asked him how much longer he could continue like this, and Shih Ch'un replied that there was no limit; possibly several dozen years, his only fear being that he might die of old age, but it would not be of hunger. The emperor then discontinued the experiment and sent him away. Note that Shih Ch'un's statement shows that giving up starches cannot protract one's years. Some today possess Shih Ch'un's method. (15, tr. Ware 1966:248-9)
Human right to water and sanitation
Following intense negotiations, 122 countries formally acknowledged "the Human Right to Water and Sanitation" in General Assembly Resolution 64/292 on 28 July 2010. It recognized the right of every human being to have access to sufficient water for personal and domestic uses (between 50 and 100 liters of water per person per day), which must be safe, acceptable and affordable (water costs should not exceed 3% of household income), and physically accessible (the water source has to be within 1,000 meters of the home and collection time should not exceed 30 minutes)." The General Assembly declared that clean drinking water is "essential to the full enjoyment of life and all other human rights". In September 2010, the UN Human Rights Council adopted a resolution recognizing that the human right to water and sanitation forms part of the right to an adequate standard of living.
End Water Poverty
End Water Poverty is an international campaign calling for sanitation and potable water for all. UN figures show that worldwide, 2.6 billion people live without anywhere to excrete in a sanitary manner and over one billion have no safe water to drink. Over 4,900 children every day from preventable water-related diseases.
Biological half-life
The biological half-life of water in a human is about 7 to 14 days. It can be altered by behavior. Drinking large amounts of alcohol will reduce the biological half-life of water in the body. This has been used to decontaminate humans who are internally contaminated with tritiated water (tritium). The basis of this decontamination method (used at Harwell) is to increase the rate at which the water in the body is replaced with new water.
Geoduck
Geoducks are one of the longest-living organisms in the animal kingdom. The oldest recorded specimen was 168 years old, but individuals usually live up to 140 years. A geoduck sucks water containing plankton down through its long siphon, filters this for food and ejects its refuse out through a separate hole in the siphon. Adult geoducks have few natural predators, which may also contribute to their longevity. In Alaska, sea otters and dogfish have proved capable of dislodging geoducks; starfish also attack and feed on the exposed geoduck siphon.
Famine
After China and India, there is a second tier of smaller countries with large water deficits – Algeria, Egypt, Iran, Mexico, and Pakistan. Four of these already import a large share of their grain. Only Pakistan remains marginally self-sufficient. But with a population expanding by 4 million a year, it will also soon turn to the world market for grain. According to a UN climate report, the Himalayan glaciers that are the principal dry-season water sources of Asia's biggest rivers – Ganges, Indus, Brahmaputra, Yangtze, Mekong, Salween and Yellow – could disappear by 2350 as temperatures rise and human demand rises. Approximately 2.4 billion people live in the drainage basin of the Himalayan rivers. India, China, Pakistan, Afghanistan, Bangladesh, Nepal and Myanmar could experience floods followed by severe droughts in coming decades. In India alone, the Ganges provides water for drinking and farming for more than 500 million people.
The Source (Ayreon album)
After finally escaping from Alpha, the surviving humans are injected with a drug made by The Chemist (Tommy Rogers), named "Liquid Eternity" but mostly referred to as "The Source", that will make their bodies able to live underwater and communicate by telepathy, as the world they are going to is an aquatic one; it will also drastically extend their lifespans, making them virtually immortal. They put themselves in suspended animation, as their trip will take many years ("Aquatic Race"). In their sleep, the humans dream of the beautiful world that awaits them ("The Dream Dissolves"). The former Alphans ultimately awaken as they reach Sirrah and mourn, aware that during the many years it took them to travel, their planet, together with all their loved ones, has come to an end ("Deathcry of a Race"). However, they are also filled with hope at the sight of their new world ("Into the Ocean").
Inedia
Some breatharians have submitted themselves to medical testing, including a hospital's observation of Indian mystic Prahlad Jani appearing to survive without food or water for 15 days, and an Israeli breatharian appearing to survive for eight days on a television documentary. In a handful of documented cases, individuals attempting breatharian fasting have died. Among the claims in support of Inedia investigated by the Indian Rationalist Association, all were found to be fraudulent. In other cases, people have attempted to survive on sunlight alone, only to abandon the effort after losing a large percentage of their body weight.
Inedia
In a television documentary produced by the Israeli television investigative show "The Real Face" (פנים אמיתיות) hosted by Amnon Levy, Israeli practitioner of Inedia Ray Maor (ריי מאור) who appeared to survive without food or water for eight days and eight nights. According to the documentary, he was restricted to a small villa and placed under constant video surveillance, with medical supervision that included daily blood testing. The documentary claimed Maor was in good spirits throughout the experiment, lost 17 lb after eight days, blood tests showed no change before, during or after the experiment, and Cardiologist Ilan Kitsis from Tel Aviv Sourasky Medical Center was "baffled."Hindu religious texts contain account of saints and hermits practicing what would be called inedia, breatharianism or Sustenance through Light in modern terms. In Valmiki's Ramayana, Book III, Canto VI, an account of anchorites and holy men is given, who flocked around Rama when he came to Śarabhanga's hermitage. These included, among others, the "...saints who live on rays which moon and daystar give" and "those ... whose food the wave of air supplies". In Canto XI of the same book a hermit named Māṇḍakarṇi is mentioned: "For he, great votarist, intent – On strictest rule his stern life spent – ... – Ten thousand years on air he fed..." (English quotations are from Ralph T. H. Griffith's translation).
Hydrothermal vent
While chemosynthesis occurring at the deep ocean allows organisms to live without sunlight in the immediate sense, they technically still rely on the sun for survival, since oxygen in the ocean is a byproduct of photosynthesis. However, if the sun were to suddenly disappear and photosynthesis ceased to occur on our planet, life at the deep-sea hydrothermal vents could continue for millennia (until the oxygen was depleted).
Hydrosphere
"Specific water availability is the residual (after use) per capita quantity of fresh water." Fresh water resources are unevenly distributed in terms of space and time and can go from floods to water shortages within months in the same area. In 1998 76% of the total population had a specific water availability of less than 5.0 thousand m3 per year per capita. Already by 1998, 35% of the global population suffered "very low or catastrophically low water supplies" and Shiklomanov predicted that the situation would deteriorate in the twenty-first century with "most of the Earth's population will be living under the conditions of low or catastrophically low water supply" by 2025. There is only 2.5% of fresh water in the hydrosphere and only 0.25% of water is accessible for our use.
Eternals (comics)
Due to the cosmic energy that suffuses an Eternal's body and the nigh-unbreakable mental hold they have over their physiological processes, the Eternals of Earth are effectively immortal. They live for millennia, do not fatigue from physical exertion, are immune to disease and poison, and are unaffected by environmental extremes of cold and heat. Most cannot be injured by conventional weaponry, and even if they somehow are, an Eternal can rapidly regenerate any damage as long as they are able to retain their mental hold over their bodies; this mental bond can be broken however. In the 2006 series it was also stated that Eternals are able to absorb oxygen directly from water, and therefore cannot drown. In the same series, Ikaris was plunged into molten metal and experienced great pain, but no physical injury, which the Deviants attributed to a forcefield which protects Ikaris even when unconscious. It is unclear if all Eternals share this degree of protection.
Inedia
Prahlad Jani is an Indian sadhu who says he has lived without food and water for more than 70 years. His claims were investigated by doctors at Sterling Hospital, Ahmedabad, Gujarat in 2003 and 2010. The study concluded that Prahlad Jani was able to survive under observation for two weeks without either food or water, and had passed no urine or stool, with no need for dialysis. Interviews with the researchers speak of strict observation and relate that round-the-clock observation was ensured by multiple CCTV cameras. Jani was subjected to multiple medical tests, and his only contact with any form of fluid was during bathing and gargling, with the fluid spat out measured by the doctors. The research team could not comment on his claim of having been able to survive in this way for decades.
Water
The UN World Water Development Report (WWDR, 2003) from the World Water Assessment Program indicates that, in the next 20 years, the quantity of water available to everyone is predicted to decrease by 30%. 40% of the world's inhabitants currently have insufficient fresh water for minimal hygiene. More than 2.2 million people died in 2000 from waterborne diseases (related to the consumption of contaminated water) or drought. In 2004, the UK charity WaterAid reported that a child dies every 15 seconds from easily preventable water-related diseases; often this means lack of sewage disposal; see toilet.
Underwater habitat
Underwater habitats are underwater structures in which people can live for extended periods and carry out most of the basic human functions of a 24-hour day, such as working, resting, eating, attending to personal hygiene, and sleeping. In this context 'habitat' is generally used in a narrow sense to mean the interior and immediate exterior of the structure and its fixtures, but not its surrounding marine environment. Most early underwater habitats lacked regenerative systems for air, water, food, electricity, and other resources. However, recently some new underwater habitats allow for these resources to be delivered using pipes, or generated within the habitat, rather than manually delivered.
Tritiated water
Tritiated water can be used to measure the total volume of water in one's body. Tritiated water distributes itself into all body compartments relatively quickly. The concentration of tritiated water in urine is assumed to be similar to the concentration of tritiated water in the body. Knowing the original amount of tritiated water that was ingested and the concentration, one can calculate the volume of water in the body.Tritiated water contains the radioactive hydrogen isotope tritium. As a low energy beta emitter with a half-life of about 12 years, it is not dangerous externally because its beta particles are unable to penetrate the skin. However, it is a radiation hazard when inhaled, ingested via food or water, or absorbed through the skin. HTO has a short biological half-life in the human body of 7 to 14 days, which both reduces the total effects of single-incident ingestion and precludes long-term bioaccumulation of HTO from the environment. Biological half-life of tritiated water in the human body, which is a measure of body water turnover, varies with season. Studies on the biological half-life of occupational radiation workers for free water tritium in the coastal region of Karnataka, India show that the biological half-life in the winter season is twice that of the summer season.
Space and survival
Many of the same existential risks to humanity would destroy parts or all of Earth's biosphere as well. And although many have speculated about life and intelligence existing in other parts of space, Earth is the only place in the universe known to harbor life. Eventually the Earth will be uninhabitable, at the latest when the Sun becomes a red giant in about 5 billion years. Mankind, or its intelligent descendants, then has to leave the Solar System to ensure survival of the human species.
Peak water
The quality of drinking water is vital for human health. Peak water constraints result in people not having access to safe water for basic personal hygiene. "Infectious waterborne diseases such as diarrhea, typhoid, and cholera are responsible for 80 percent of illnesses and deaths in the developing world, many of them children. One child dies every eight seconds from a waterborne disease; 15 million children a year."
Water
Light in the visible electromagnetic spectrum can traverse a couple meters of pure water (or ice) without significant absorption, so that it looks transparent and colorless. Thus aquatic plants, algae, and other photosynthetic organisms can live in water up to hundreds of meters deep, because sunlight can reach them. Water vapour is essentially invisible as a gas.
Béla Bicsérdy
In the 1920s, Bicsérdy inspired a great many people in Transylvania and Hungary promoting a regime of a raw vegan diet (mostly fruits with some bread and raw milk), regular fasting, sunbathing, daily outdoor exercising and regular water-cure. He claimed that any person who followed his regime will be cured of illness and will live hundreds of years, just as known possible from ancient times (the Bible for example reported many long-lived people).
Fluid balance
The amount of water varies with the individual, as it depends on the condition of the subject, the amount of physical exercise, and on the environmental temperature and humidity. In the US, the reference daily intake (RDI) for water is 3.7 litres per day (l/day) for human males older than 18, and 2.7 l/day for human females older than 18 including water contained in food, beverages, and drinking water. The common misconception that everyone should drink two litres (68 ounces, or about eight 8-oz glasses) of water per day is not supported by scientific research. Various reviews of all the scientific literature on the topic performed in 2002 and 2008 could not find any solid scientific evidence that recommended drinking eight glasses of water per day. For example, people in hotter climates will require greater water intake than those in cooler climates. An individual's thirst provides a better guide for how much water they require rather than a specific, fixed number. A more flexible guideline is that a normal person should urinate 4 times per day, and the urine should be a light yellow color.
Tardigrade
Tardigrades are considered to be able to survive even complete global mass extinction events due to astrophysical events, such as gamma-ray bursts, or large meteorite impacts. Some of them can withstand extremely cold temperatures down to (close to absolute zero), while others can withstand extremely hot temperatures up to for several minutes, pressures about six times greater than those found in the deepest ocean trenches, ionizing radiation at doses hundreds of times higher than the lethal dose for a human, and the vacuum of outer space. They can go without food or water for more than 30 years, drying out to the point where they are 3% or less water, only to rehydrate, forage, and reproduce. Tardigrades that live in harsh conditions undergo an annual process of cyclomorphosis, allowing for survival in sub-zero temperatures.
Space Saves Society
Water covers the largest percentage of our planet’s surface and it is vital for our survival. However, many areas still suffer from absence of drinking water. The Water Supply and Sanitation Collaborative Council (WSSCC) refers that “Today 2.5 billion people, including almost one billion children, live without even basic sanitation. Every 20 seconds, a child dies as a result of poor sanitation. That's 1.5 million preventable deaths each year.”
Planetary habitability
An absolute requirement for life is an energy source, and the notion of planetary habitability implies that many other geophysical, geochemical, and astrophysical criteria must be met before an astronomical body can support life. In its astrobiology roadmap, NASA has defined the principal habitability criteria as "extended regions of liquid water, conditions favorable for the assembly of complex organic molecules, and energy sources to sustain metabolism". In August 2018, researchers reported that water worlds could support life.
Nanotechnology for water purification
Water is the most essential element to every life on this Earth. It’s a substance composed of the chemical elements hydrogen and oxygen. Water has always played a prominent role in human civilization. A sufficient supply of safe drinking water is one of the important requirement for a healthy life, but waterborne diseases plays a deadly role in creating large numbers of deaths in many parts of the world. All living things require water to grow and reproduce their own kind. Water is a tasteless and odorless liquid at room temperature. Water is the only substance that occurs naturally as a solid in the form of ice, a liquid and a gas which is in the form of water vapor. Water covers 71% of the entire Earth surface. The amount of water in this world isn't diminishing, but the demand is steadily increasing. Scientists believe that the world's population, will double by 2050. In addition to this, the amount of fresh water that is clean and safe to drink is steadily decreasing because of pollutants. So, people are in need of drinking water in its purest form. There are plenty of water purifiers available in the market which use different techniques like boiling, filtration, distillation, chlorination, sedimentation and oxidation. Currently nanotechnology plays a vital role in water purification techniques. In nanotechnology, nano membranes are used with the purpose of softening the water and removal of contaminants such as physical, biological and chemical contaminants. There are variety of techniques in nanotechnology which uses nano particles for providing safe drinking water with a high level of effectiveness. Some techniques have become commercialized.
Dog whelk
The dog whelk can only survive out of water for a limited period, as it will gradually become desiccated and die if emersed for too long. Metabolic processes within cells take place in solution, and a decrease in water content makes it impossible for the organism to function properly. In experiments it has been shown that 50% of dog whelks die at 40 °C, and it can be assumed that at temperatures lower than this a smaller proportion will be killed off. Furthermore, the dog whelk has to excrete ammonia directly into water, as it does not have the adaptation possessed by many upper shore species which would allow it to produce uric acid for excretion without loss of water. When kept emersed for seven days at a temperature of 18 °C, 100% of dog whelks die, in contrast to many periwinkle species which can lose even more water than the dog whelk (i.e. more than 37% of their total body mass) but survive as a result of their ability to excrete toxic waste products more efficiently.
Drinking
A daily intake of water is required for the normal physiological functioning of the human body. The USDA recommends a daily intake of "total water": not necessarily by drinking but by consumption of water contained in other beverages and foods. The recommended intake is 3.7 liters (appx. 1 gallon) per day for an adult male, and 2.7 liters (appx. 0.75 gallon) for an adult female. Other sources, however, claim that a high intake of fresh drinking water, separate and distinct from other sources of moisture, is necessary for good health – eight servings per day of eight fluid ounces (1.8 liters, or 0.5 gallon) is the amount recommended by many nutritionists, although there is no scientific evidence supporting this recommendation.
Entropy and life
For nearly a century and a half, beginning with Clausius' 1863 memoir "On the Concentration of Rays of Heat and Light, and on the Limits of its Action", much writing and research has been devoted to the relationship between thermodynamic entropy and the evolution of life. The argument that life feeds on negative entropy or negentropy was asserted by physicist Erwin Schrödinger in a 1944 book "What is Life?". He posed, "How does the living organism avoid decay?" The obvious answer is: "By eating, drinking, breathing and (in the case of plants) assimilating." Recent writings have used the concept of Gibbs free energy to elaborate on this issue.
While energy from nutrients is necessary to sustain an organism's order, there is also the Schrödinger prescience: "An organism's astonishing gift of concentrating a stream of order on itself and thus escaping the decay into atomic chaos – of drinking orderliness from a suitable environment – seems to be connected with the presence of the aperiodic solids..." We now know that the 'aperiodic' crystal is DNA and that the irregular arrangement is a form of information. "The DNA in the cell nucleus contains the master copy of the software, in duplicate. This software seems to control by "specifying an algorithm, or set of instructions, for creating and maintaining the entire organism containing the cell." DNA and other macromolecules determine an organism's life cycle: birth, growth, maturity, decline, and death. Nutrition is necessary but not sufficient to account for growth in size as genetics is the governing factor. At some point, organisms normally decline and die even while remaining in environments that contain sufficient nutrients to sustain life. The controlling factor must be internal and not nutrients or sunlight acting as causal exogenous variables. Organisms inherit the ability to create unique and complex biological structures; it is unlikely for those capabilities to be reinvented or be taught each generation. Therefore, DNA must be operative as the prime cause in this characteristic as well. Applying Boltzmann's perspective of the second law, the change of state from a more probable, less ordered and high entropy arrangement to one of less probability, more order, and lower entropy seen in biological ordering calls for a function like that known of DNA. DNA's apparent information processing function provides a resolution of the paradox posed by life and the entropy requirement of the second law.
Therese Neumann
Montague Summers in his book "The Physical Phenomena of Mysticism" speaks of her supposedly supernatural ability to survive for long periods without food or water.
Effect of spaceflight on the human body
Human physiology is adapted to living within the atmosphere of Earth, and a certain amount of oxygen is required in the air we breathe. If the body does not get enough oxygen, then the astronaut is at risk of becoming unconscious and dying from hypoxia. In the vacuum of space, gas exchange in the lungs continues as normal but results in the removal of all gases, including oxygen, from the bloodstream. After 9 to 12 seconds, the deoxygenated blood reaches the brain, and it results in the loss of consciousness. Exposure to vacuum for up to 30 seconds is unlikely to cause permanent physical damage. Animal experiments show that rapid and complete recovery is normal for exposures shorter than 90 seconds, while longer full-body exposures are fatal and resuscitation has never been successful. There is only a limited amount of data available from human accidents, but it is consistent with animal data. Limbs may be exposed for much longer if breathing is not impaired.
Harmony with nature
16. Without water, there is no life. Humans and all living things have the right to water, but water also has rights. All States and peoples worldwide should work together in solidarity to ensure that loss of vegetation, deforestation, the pollution of the atmosphere and contamination are prevented from continuing to alter the hydrological cycle. These cause desertification, lack of food, temperature increase, sea level rise, migrations, acid rain, and physical-chemical changes that can cause ecosystems to die.
Biochemical oxygen demand
Although the Royal Commission on Sewage Disposal proposed 5 days as an adequate test period for rivers of the United Kingdom of Great Britain and Ireland, longer periods were investigated for North American rivers. Incubation periods of 1, 2, 5, 10 and 20 days were being used into the mid-20th century. Keeping dissolved oxygen available at their chosen temperature, investigators found up to 99 percent of total BOD was exerted within 20 days, 90 percent within 10 days, and approximately 68 percent within 5 days. Variable microbial population shifts to nitrifying bacteria limit test reproducibility for periods greater than 5 days. The 5-day test protocol with acceptably reproducible results emphasizing carbonaceous BOD has been endorsed by the United States Environmental Protection Agency. This 5-day BOD test result may be described as the amount of oxygen required for aquatic microorganisms to stabilize decomposable organic matter under aerobic conditions. Stabilization, in this context, may be perceived in general terms as the conversion of food to living aquatic fauna. Although these fauna will continue to exert biochemical oxygen demand as they die, that tends to occur within a more stable evolved ecosystem including higher trophic levels.
Most pristine rivers will have a 5-day carbonaceous BOD below 1 mg/L. Moderately polluted rivers may have a BOD value in the range of 2 to 8 mg/L. Rivers may be considered severely polluted when BOD values exceed 8 mg/L. Municipal sewage that is efficiently treated by a three-stage process would have a value of about 20 mg/L or less. Untreated sewage varies, but averages around 600 mg/L in Europe and as low as 200 mg/L in the U.S., or where there is severe groundwater or surface water Infiltration/Inflow. The generally lower values in the U.S. derive from the much greater water use per capita than in other parts of the world.
Suicide methods
Death from dehydration can take from several days to a few weeks. This means that unlike many other suicide methods, it cannot be accomplished impulsively. Those who die by terminal dehydration typically lapse into unconsciousness before death, and may also experience delirium and deranged serum sodium. Discontinuation of hydration does not produce true thirst, although a sensation of dryness of the mouth often is reported as "thirst." The evidence this is not true thirst is extensive and shows the ill feeling is not relieved by giving fluids intravenously, but is relieved by wetting the tongue and lips and proper care of the mouth. Patients with edema tend to take longer to die of dehydration because of the excess fluid in their bodies.
Half-life
For example, the biological half-life of water in a human being is about 9 to 10 days, though this can be altered by behavior and various other conditions. The biological half-life of caesium in human beings is between one and four months.
Inedia
Inedia (Latin for "fasting") or breatharianism is the belief that it is possible for a person to live without consuming food. Breatharians claim that food, and in some cases water, are not necessary for survival, and that humans can be sustained solely by "prana", the vital life force in Hinduism. According to Ayurveda, sunlight is one of the main sources of "prana", and some practitioners believe that it is possible for a person to survive on sunlight alone. The terms "breatharianism" or "inedia" may also refer to this philosophy when it is practiced as a lifestyle in place of the usual diet.
Fresh water
Water is critical to the survival of all living organisms. Some organisms can thrive on salt water, but the great majority of higher plants and most mammals need fresh water to live.
Survival skills
A lack of water causes dehydration, which may result in lethargy, headaches, dizziness, confusion, and eventually death. Even mild dehydration reduces endurance and impairs concentration, which is dangerous in a survival situation where clear thinking is essential. Dark yellow or brown urine is a diagnostic indicator of dehydration. To avoid dehydration, a high priority is typically assigned to locating a supply of drinking water and making provision to render that water as safe as possible.
Space suit
The human body can briefly survive the hard vacuum of space unprotected, despite contrary depictions in some popular science fiction. Human flesh expands to about twice its size in such conditions, giving the visual effect of a body builder rather than an overfilled balloon. Consciousness is retained for up to 15 seconds as the effects of oxygen starvation set in. No snap freeze effect occurs because all heat must be lost through thermal radiation or the evaporation of liquids, and the blood does not boil because it remains pressurized within the body.
Bottled water
Bottled water is often stored as part of an emergency kit in case of natural disaster. The U.S. Federal Emergency Management Agency (FEMA) says the "safest" and "most reliable" source of drinking water is store bought bottled water. Commonly, disaster management experts recommend storing of water per person, per day for at least three days. This amount is intended to include water for drinking and cooking as well as water for hand washing, washing dishes, and personal hygiene. Factory-containers of water have an indefinite shelf life, as long as they remain unopened and undamaged. The sell-by date is voluntarily and individually set by manufacturers to indicate the length of time that they believe the water will taste and smell fresh, rather than to indicate any issue of contamination or food safety.
Pleopeltis polypodioides
The resurrection fern gets its name because it can survive long periods of drought by curling up its fronds and appearing desiccated, grey-brown and dead. However, when just a little water is present, the fern will uncurl and reopen, appearing to "resurrect" and restoring itself to a vivid green color within about 24 hours. It has been estimated that these plants could last 100 years without water and still revive after a single exposure.
Water
Fifty years ago, the common perception was that water was an infinite resource. At the time, there were fewer than half the current number of people on the planet. People were not as wealthy as today, consumed fewer calories and ate less meat, so less water was needed to produce their food. They required a third of the volume of water we presently take from rivers. Today, the competition for the fixed amount of water resources is much more intense, giving rise to the concept of peak water. This is because there are now nearly seven billion people on the planet, their consumption of water-thirsty meat and vegetables is rising, and there is increasing competition for water from industry, urbanisation and biofuel crops. In future, even more water will be needed to produce food because the Earth's population is forecast to rise to 9 billion by 2050.
Colonization of Mars
Human survival on Mars would require living in artificial Mars habitats with complex life-support systems. One key aspect of this would be water processing systems. Being made mainly of water, a human being would die in a matter of days without it. Even a 5–8% decrease in total body water causes fatigue and dizziness and a 10% decrease physical and mental impairment (See Dehydration). A person on Earth uses 70–140 litres of water per day on average. Through experience and training, astronauts on the ISS have shown it is possible to use far less, and that around 70% of what is used can be recycled using the ISS water recovery systems. Similar systems would be needed on Mars, but would need to be much more efficient, since regular robotic deliveries of water to Mars would be prohibitively expensive (the ISS is supplied with water four times per year). Some experts have argued for setting up open-air settlements by using special construction methodologies- like excavating deep into the Martian crust to depths where air pressures may be sufficient to allow humans to survive without pressurized suits.Potential access to in-situ water (frozen or otherwise) via drilling has been investigated by NASA.
Bloodthirsty: One Nation Under Water
When Trey dies in a fire at Wolfinger Biomed, Virgil has reason to suspect that his brother was murdered. Having nothing left to live for, Virgil decides to investigate his brother's death, even if that means staying in New Orleans long enough to die in the coming hurricane. What he uncovers is an underground cabal of hemovores - "an organism that ingests blood as the main part of its diet." Unlike vampires, the hemovores in "Bloodthirsty" are not supernatural beings; they are humans with a mutated gene that controls longevity. Their bodies are in a constant state of repair, which deprives their cells of oxygen. In order to compensate for this loss, they must consume fresh (oxygenated) human blood daily or they will die.
Life on Venus
It is plausible that microbial life originated on Venus if liquid water existed on its surface prior to the heating of the planet by the runaway greenhouse effect, but no longer exists. Assuming the process that delivered water to Earth was common to all the planets near the habitable zone, it has been estimated that liquid water could have existed on its surface for up to 600 million years during and shortly after the Late Heavy Bombardment, which could be enough time for simple life to form, but this figure can vary from as little as a few million years to as much as few billion. This might also have given enough time for microbial life to evolve to be aerial. There has been very little analysis of Venusian surface material, so it is possible that evidence of past life, if it ever existed, could be found with a probe capable of enduring Venus's current extreme surface conditions, although the resurfacing of the planet in the past 500 million years means that it is unlikely that ancient surface rocks remain, especially those containing the mineral tremolite which, theoretically, could have encased some biosignatures.
Prahlad Jani
Two observational studies of Jani have been conducted, one in 2003 and one in 2010, both involving Dr Sudhir Shah, a neurologist at the Sterling Hospitals in Ahmedabad, India, who had studied people claiming to have exceptional abilities, including other fasters such as Hira Ratan Manek. In both cases the investigators confirmed Jani's ability to survive healthily without food and water during the testing periods, although neither study was submitted to a scientific journal. When questioned six days into the 2010 experiment, the DRDO spokesperson announced that the study's findings would be "confidential" until results were established, and a further official press release by the team stated that any inside analysis information may be disclosed only at the discretion of the principal investigator, DIPAS. Uninvolved doctors and other critics have questioned the validity of the studies and stated their belief that, although people can survive for days without food or water, it is not possible to survive for years, especially since glucose, a substrate critical to brain function, isn't provided. The veracity of Mataji's claims has also never been independently confirmed with all tests being indigenously conducted.
Hypothermia
Those who are stiff with pupils that do not move may survive if treated aggressively. Survival with good function also occasionally occurs even after the need for hours of CPR. Children who have near-drowning accidents in water near can occasionally be revived, even over an hour after losing consciousness. The cold water lowers the metabolism, allowing the brain to withstand a much longer period of hypoxia. While survival is possible, mortality from severe or profound hypothermia remains high despite optimal treatment. Studies estimate mortality at between 38% and 75%.
Bactrian camel
Bactrian camels are exceptionally adept at withstanding wide variations in temperature, ranging from freezing cold to blistering heat. They have a remarkable ability to go without water for months at a time, but when water is available they may drink up to 57 liters at once. When well fed, the humps are plump and erect, but as resources decline, the humps shrink and lean to the side. When moving faster than a walking speed, they pace, by stepping forwards with both legs on the same side (as opposed to trotting, using alternate diagonals as done by most other quadrupeds). Speeds of up to have been recorded, but they rarely move this fast. Bactrian camels are also said to be good swimmers. The sense of sight is well developed and the sense of smell is extremely good. The lifespan of Bactrian camels is estimated at up to 50 years, often 20 to 40 in captivity.
Jill Farrant
Farrant is investigating the ability of certain species of plants which are able to survive without water for long periods of time. As Farrant explains, "[a]ll plants have the genes that enable desiccation tolerance, but most use them only when they make seeds. Resurrection plants can also switch these genes on in their leaves and roots whenever drought occurs." The ultimate goal of her research is to find applications that will lead to the development of drought-tolerant crops to nourish populations in arid, drought-prone climates, notably in Africa, and her research may have medicinal applications as well. Farrant believes food crops which can survive long stretches without water "will become more important as climate change (increasing drought) continues to impact on agriculture."
LifeStraw
The LifeStraw water filters are designed by the Swiss-based Vestergaard Frandsen. While originally developed for people living in developing nations and for distribution in humanitarian crisis, the LifeStraw has gained popularity as a consumer product. The LifeStraw is now used as a tool for survivalists and packed in emergency preparedness kits in addition to being used to help combat clean water scarcity worldwide. LifeStraw personal filters can provide clean water for up to a year, and the LifeStraw Family filters a maximum of 18,000 litres of water, providing safe drinking water for a family of five for up to three years.
Water scarcity
Hydrologists today typically assess water scarcity by looking at the population-water equation. This is done by comparing the amount of total available water resources per year to the population of a country or region. A popular approach to measuring water scarcity has been to rank countries according to the amount of annual water resources available per person. For example, according to the Falkenmark Water Stress Indicator, a country or region is said to experience "water stress" when annual water supplies drop below 1,700 cubic metres per person per year. At levels between 1,700 and 1,000 cubic metres per person per year, periodic or limited water shortages can be expected. When water supplies drop below 1,000 cubic metres per person per year, the country faces "water scarcity". The United Nations' FAO states that by 2025, 1.9 billion people will live in countries or regions with absolute water scarcity, and two-thirds of the world population could be under stress conditions. The World Bank adds that climate change could profoundly alter future patterns of both water availability and use, thereby increasing levels of water stress and insecurity, both at the global scale and in sectors that depend on water.
Khader Adnan
Almost two months into his hunger strike, it was reported that Adnan agreed to having electrolytes, vitamins, glucose, and salts added to the water he is drinking. His doctors noted that, "A fast in excess of 70 days does not permit survival. Infusion of liquids, adjustment of salts, and the addition of glucose and vitamin cannot prevent certain death due to such a protracted hunger strike."
Drinking water
The amount of drinking water required is variable. It depends on physical activity, age, health, and environmental conditions. In a temperate climate under normal conditions, adequate water intake is about for adult women and for adult men. Physical exercise and heat exposure cause loss of water and therefore may induce thirst and greater water intake. Physically active individuals in hot climates may have total daily water needs of or more. The European Food Safety Authority recommends per day for adult women and per day for adult men.
Water intoxication
Water intoxication can be prevented if a person's intake of water does not grossly exceed their losses. Healthy kidneys are able to excrete approximately 800 millilitres to 1 litre of fluid water (0.84 - 1.04 quarts) per hour. However, stress (from prolonged physical exertion), as well as disease states, can greatly reduce this amount.
Feeding Everyone No Matter What
As a backup plan, it is even possible that humans could eat this predigested biomass. In a sun-obscuring crisis, stored food would last the human population less than one year. The book shows how many of these solutions can be ramped up in less than one year.
Passenger pigeon
The passenger pigeon drank at least once a day, typically at dawn, by fully inserting its bill into lakes, small ponds, and streams. Pigeons were seen perching on top of each other to access water, and if necessary, the species could alight on open water to drink. One of the primary causes of natural mortality was the weather, and every spring many individuals froze to death after migrating north too early. In captivity, a passenger pigeon was capable of living at least 15 years; Martha, the last known living passenger pigeon, was at least 17 and possibly as old as 29 when she died. It is undocumented how long a wild pigeon lived.
Health effects of radon
The effects of radon, if found in food or drinking water, are unknown. Following ingestion of radon dissolved in water, the biological half-life for removal of radon from the body ranges from 30 to 70 minutes. More than 90% of the absorbed radon is eliminated by exhalation within 100 minutes, By 600 minutes, only 1% of the absorbed amount remains in the body.
Halicephalobus mephisto
"Halicephalobus mephisto" is resistant to high temperatures, it reproduces asexually, and feeds on subterranean bacteria. According to radiocarbon dating, these worms live in groundwater that is 3,000–12,000 years old. The worms are also able to survive in waters with extremely low levels of oxygen, lower than one percent of the level of most oceans. It is named after Mephistopheles, which means "he who loves not the light" and alludes to the fact it is found so deep under the Earth's surface.
Drinking
Like nearly all other life forms, humans require water for tissue hydration. Lack of hydration causes thirst, a desire to drink which is regulated by the hypothalamus in response to subtle changes in the body's electrolyte levels and blood volume. A decline in total body water is called dehydration and will eventually lead to death by hypernatremia. Methods used in the management of dehydration include assisted drinking or oral rehydration therapy.
Narwhal
Narwhals can live up to at least 50 years. Mortality often occurs when the narwhals suffocate after they fail to leave before the surface of the Arctic waters freeze over in the late autumn. As narwhals need to breathe, they drown if open water is no longer accessible and the ice is too thick for them to break through. Maximum aerobic swimming distance between breathing holes in ice is less than which limits the use of foraging grounds, and these holes must be at least wide to allow an adult whale to breathe. The last major entrapment events occurred when there was little to no wind. Entrapment can affect as many as 600 individuals, most occurring in narwhal wintering areas such as Disko Bay. In the largest entrapment in 1915 in West Greenland, over 1,000 narwhals were trapped under the ice.
Elixir of life
In the eight-century "Man'yōshū", 'waters of rejuvenation' (, ) are said to be in the possession of the moon god Tsukuyomi. Similarities have been noted with a folktale from the Ryukyu Islands, in which the moon god decides to give man the water of life (), and serpents the water of death (sïnimizï). However, the person entrusted with carrying the pails down to Earth gets tired and takes a break, and a serpent bathes in the water of life, rendering it unusable. This is said to be why serpents can rejuvenate themselves each year by shedding their skin while men are doomed to die.
Fish physiology
Breathing air is primarily of use to fish that inhabit shallow, seasonally variable waters where the water's oxygen concentration may seasonally decline. Fish dependent solely on dissolved oxygen, such as perch and cichlids, quickly suffocate, while air-breathers survive for much longer, in some cases in water that is little more than wet mud. At the most extreme, some air-breathing fish are able to survive in damp burrows for weeks without water, entering a state of aestivation (summertime hibernation) until water returns.
Cryptobiosis
Anhydrobiosis is the most studied form of cryptobiosis and occurs in situations of extreme desiccation. The term "anhydrobiosis" derives from the Greek for "life without water" and is most commonly used for the desiccation tolerance observed in certain invertebrate animals such as bdelloid rotifers, tardigrades, brine shrimp, nematodes, and at least one insect, a species of chironomid ("Polypedilum vanderplanki"). However, other life forms, including the resurrection plant "Craterostigma plantagineum", the majority of plant seeds, and many microorganisms such as bakers' yeast, also exhibit desiccation tolerance. Studies have shown that some anhydrobiotic organisms can survive for decades, even centuries, in the dry state.
UN-Water
The physical world of water is closely bound up with the socio-political world, with water often a key factor in managing risks such as famine, migration, epidemics, inequalities and political instability. Since 1900, more than 11 million people have died as a consequence of drought and more than 2 billion have been affected by drought, more than any other physical hazard.
Water scarcity in Africa
The most immediately apparent impact of water scarcity in Africa is on the continent's health. With a complete lack of water, humans can only live up to 3 to 5 days on average. This often forces those living in water deprived regions to turn to unsafe water resources, which, according to the World Health Organization, contributes to the spread of waterborne diseases including typhoid fever, cholera, dysentery and diarrhea, and to the spread of diseases such as malaria whose vectors rely on such water resources, and can lead to diseases such as trachoma, plague, and typhus. Additionally, water scarcity causes many people to store water within the household, which increases the risk of household water contamination and incidents of malaria and dengue fever spread by mosquitoes. These waterborne diseases are not usually found in developed countries because of sophisticated water treatment systems that filter and chlorinate water, but for those living with less developed or non-existent water infrastructure, natural, untreated water sources often contain tiny disease-carrying worms and bacteria. Although many of these waterborne sicknesses are treatable and preventable, they are nonetheless one of the leading causes of disease and death in the world. Globally, 2.2 million people die each year from diarrhea-related disease, and at any given time fifty percent of all hospital beds in the world are occupied by patients suffering from water-related diseases. Infants and children are especially susceptible to these diseases because of their young immune systems, which lends to elevated infant mortality rates in many regions of Africa. Water scarcity has a big impact on hygiene.
Water
The existence of liquid water, and to a lesser extent its gaseous and solid forms, on Earth are vital to the existence of life on Earth as we know it. The Earth is located in the habitable zone of the solar system; if it were slightly closer to or farther from the Sun (about 5%, or about 8 million kilometers), the conditions which allow the three forms to be present simultaneously would be far less likely to exist.
Vegetarianism
Research funded by the U.S. National Institutes of Health has shown that the average Adventist in California lives 4 to 10 years longer than the average Californian. The research, as cited by the cover story of the November 2005 issue of "National Geographic", asserts that Adventists live longer because they do not smoke or drink alcohol, have a day of rest every week, and maintain a healthy, low-fat vegetarian diet that is rich in nuts and beans. The cohesiveness of Adventists' social networks has also been put forward as an explanation for their extended lifespan.
Since Dan Buettner's 2005 "National Geographic" story about Adventist longevity, his book, "The Blue Zones: Lessons for Living Longer From the People Who've Lived the Longest", named Loma Linda, California a "blue zone" because of the large concentration of Seventh-day Adventists. He cites the Adventist emphasis on health, diet, and Sabbath-keeping as primary factors for Adventist longevity.
Water security
Water, in absolute terms, is not in short supply planet-wide. But, according to the United Nations water organization, UN-Water, the total usable freshwater supply for ecosystems and humans is only about 200,000 km of water – less than one percent (<1%) of all freshwater resources. Usable fresh water includes water not contaminated or degraded by water-altering chemicals, such as sewage or any other harmful chemicals from continuous previous use. In the 20th century, water use has been growing at more than twice the rate of the population increase. Specifically, water withdrawals are predicted to increase by 50 percent by 2025 in developing countries, and 18 per cent in developed countries. One continent, for example, Africa, has been predicted to have 75 to 250 million inhabitants lacking access to fresh water. By 2025, 1.8 billion people will be living in countries or regions with absolute water scarcity, and two-thirds of the world population could be under stress conditions. By 2050, more than half of the world's population will live in water-stressed areas, and another billion may lack sufficient water, MIT researchers find.
One Water
The UN World Water Development Report (WWDR, 2003) from the World Water Assessment Program indicates that, in the next 20 years, the quantity of water available to everyone is predicted to decrease by 30 percent. 40 percent of the world's inhabitants currently have insufficient fresh water for minimal hygiene. More than 2.2 million people died in 2000 from waterborne diseases (related to the consumption of contaminated water) or drought. In 2004, the UK charity WaterAid reported that a child dies every 15 seconds from easily preventable water-related diseases.
Microcystin-LR
Cyanobacteria prefer to live in water bodies such as lake, ponds, reservoirs, and slow-moving streams. When the water is warm there are enough nutrients available for the bacteria to survive. Most cyanobacteria produce toxins, of which microcystin is only one group. When a cyanobacterium dies, its cell wall degrades while the toxins are released in the water. Microcystins are extremely stable in water and withstand chemical breakdown such as hydrolysis or oxidation. The half-life of this toxin is 3 weeks at pH 1 and 40 °C. At typical conditions in the environment, however, the half-life is 10 weeks.
Madre de aguas
It is said that it inhabits rivers and lakes, which never dry out while it lives there. Madre de aguas lives for hundreds of years, and anyone who tries to kill or capture it dies. It also is said to be a fearsome animal that when hungry could completely engulf a calf.
Food security in Madagascar
According to the 2009 Human Development Report of the United Nations Development Programme, about two thirds of the population live below the poverty threshold, 30 percent are illiterate, only 47 percent have access to safe water, with a life expectancy at birth of 61 years. Madagascar ranked 135th out of 169 countries in the human development index.
Waseda University
On October 21, 2007, Waseda University celebrated its 125th anniversary. Ōkuma often talked about the "125 years of life" theory: "The lifespan of a human being can be as long as 125 years. He will be able to live out his natural lifespan as long as he takes proper care of his health", because "physiologists say that every animal has the ability to live five times as long as its growth period. Since a man is said to require about 25 years to become fully mature, it follows that he can live up to 125 years of age." This theory propounded by Ōkuma was very popular and often referred to in the media of the time.
Deuterium
Deuterium can replace the normal hydrogen in water molecules to form heavy water (DO), which is about 10.6% denser than normal water (so that ice made from it sinks in ordinary water). Heavy water is slightly toxic in eukaryotic animals, with 25% substitution of the body water causing cell division problems and sterility, and 50% substitution causing death by cytotoxic syndrome (bone marrow failure and gastrointestinal lining failure). Prokaryotic organisms, however, can survive and grow in pure heavy water, though they develop slowly. Despite this toxicity, consumption of heavy water under normal circumstances does not pose a health threat to humans. It is estimated that a person might drink of heavy water without serious consequences. Small doses of heavy water (a few grams in humans, containing an amount of deuterium comparable to that normally present in the body) are routinely used as harmless metabolic tracers in humans and animals.
Tamara Rahn
Thanks to her alien physiology, Tamara has superhuman strength on Earth, which increases under water, although she has an inability to breathe out of water in Earth air for more than a few minutes without artificial aid. She has superhuman water speed, stamina, and durability. She has the ability to survive underwater for indefinite periods, and specially developed vision which gives her the ability to see clearly in the murky depths of the ocean.
Biological immortality
Hydras are a genus of the Cnidaria phylum. All cnidarians can regenerate, allowing them to recover from injury and to reproduce asexually. Hydras are simple, freshwater animals possessing radial symmetry and no post-mitotic cells. All hydra cells continually divide. It has been suggested that hydras do not undergo senescence, and, as such, are biologically immortal. In a four-year study, 3 cohorts of hydra did not show an increase in mortality with age. It is possible that these animals live much longer, considering that they reach maturity in 5 to 10 days. However, this does not explain how hydras are consequently able to maintain telomere lengths.
Science and inventions of Leonardo da Vinci
How by means of a certain machine many people may stay some time under water. How and why I do not describe my method of remaining under water, or how long I can stay without eating; and I do not publish nor divulge these by reason of the evil nature of men who would use them as means of destruction at the bottom of the sea, by sending ships to the bottom, and sinking them together with the men in them. And although I will impart others, there is no danger in them; because the mouth of the tube, by which you breathe, is above the water supported on bags of corks.
UNESCO Convention on the Protection of the Underwater Cultural Heritage
"all traces of human existence having a cultural, historical or archaeological character which have been partially or totally under water, periodically or continuously, for at least 100 years"
Radon
The effects of radon if ingested are similarly unknown, although studies have found that its biological half-life ranges from 30–70 minutes, with 90 percent removal at 100 minutes. In 1999 National Research Council investigated the issue of radon in drinking water. The risk associated with ingestion was considered almost negligible. Water from underground sources may contain significant amounts of radon depending on the surrounding rock and soil conditions, whereas surface sources generally do not.
Health in Liberia
After the thirteen year long civil war, populations in the slums of Liberia skyrocketed. At this point around 60% of the population, or 2.5 million people, do not meet the poverty line. The people were left with little choice of where to obtain water or sanitation. To date Liberia still lives with bad sanitation conditions, with up to 10 people sharing the same toilet without disinfectant and an extreme lack of clean consumable water. For every four people living in Liberia, there is one living without access to any clean drinking water or substantial sanitation. Every five deaths that occur in Liberia is due to people drinking contaminated drinking water. Due to extreme public defecation, the World Health Organisation discovered that 58% of Liberia's water was contaminated with E coli. The E coli present in the water cause many illnesses such as diarrhea and vomiting throughout the population. The water crisis in Liberia has reached catastrophic levels. Action has been taken by many non-profit organizations, one of which is called Waves for Water who are providing water filters for clean drinking water to over 60,000 Liberian people.
Inedia
Hira Ratan Manek (born 12 September 1937) claims that since 18 June 1995 he has lived on water and occasionally tea, coffee, and buttermilk. Manek states that Sungazing is the key to his health citing yogis, ancient Egyptians, Aztecs, Mayans and Native Americans as practitioners of the art. While he and his proponents state that medical experts have confirmed his ability to draw sustenance by gazing at the sun, he was caught on camera eating a big meal in a San Francisco restaurant in the 2011 documentary "Eat the Sun".
Water supply and sanitation in Ethiopia
It is important for water to be drinkable and usable for daily use. Without any clean water there would more chances at water related diseases. The World Bank also stated that in Ethiopia from 2011-2015 every 64 in 1000 infants pass away before the age of 1. So in Ethiopia there is a 6.4% chance that one's infant would not be able to survive more than one year. Also take in account that these 6.4% infants are mostly born in the rural areas of Ethiopia.
Tanka people
Some Chinese myths claim that animals were the ancestors of the Barbarians, including the Tanka people. Some ancient Chinese sources claimed that water snakes were the ancestors of the Tanka, saying that they could last for three days in the water, without breathing air.
Salt poisoning
Although humans cannot survive on seawater alone—and, indeed, will sicken quickly if they try—some people have claimed that up to two cups a day, mixed with fresh water in a 2:3 ratio, produces no ill effect. During the 18th century, British physician Richard Russell (1687–1759) advocated the practice as part of medical therapy in his country. In the 20th century, René Quinton (1866–1925), in France, would also endorse the practice. Currently, the practice is widely used in Nicaragua and other countries, supposedly taking advantage of the latest medical discoveries.) In his 1948 book, "Kon-Tiki", Thor Heyerdahl reported drinking seawater mixed with fresh in a 2:3 ratio during the 1947 expedition. The French physician Alain Bombard (1924–2005) survived an ocean crossing (1952–53) in a small Zodiac rubber boat using mainly raw fish meat, which contains about 40 percent water (like most living tissues), as well as small amounts of seawater and other provisions harvested from the ocean. His findings were challenged, but an alternative explanation was not given. A few years later, an American sailor and adventurer, William Willis (1893–1968), claimed to have drunk two cups of seawater and one cup of fresh per day for 70 days without ill effect when he lost part of his water supply.
Vulcan (Star Trek)
Vulcans are typically depicted as stronger, faster, and longer-lived than humans (although discrepancies have occurred—and although not as long as Vulcans, humans have been shown to live longer in the Star Trek universe than today—presumably as the result of advances in medical science). Vulcans are about three times as strong as an average human because of their home planet's higher gravity, although their durability is equal to humans. There are instances of them living over two hundred and twenty years. Having evolved on a desert world, Vulcans can survive without water for longer periods than humans. Vulcans can also go without sleep for as long as two weeks. Romulans are similar in appearance to Vulcans, with whom they share a common ancestry; they even appear almost identical on Starfleet sensors, with just a minute difference between them ("The Enterprise Incident").
LifeStraw
The LifeStraw is a water filter designed to be used by one person to filter water for drinking. It filters a maximum of 4000 litres of water, enough for one person for three years. It removes almost all of waterborne bacteria and parasites. In addition to the classic LifeStraw, the manufacturer also produces other styles on the LifeStraw product: the LifeStraw Family, a larger unit designed for family use, and the LifeStraw Go Water Bottle, which incorporates a LifeStraw filter into a plastic sports water bottle.
Prahlad Jani
Dr. Michael Van Rooyen, director of the Harvard Humanitarian Initiative, dismissed the observation results as "impossible", observing that the bodies of profoundly malnourished people quickly consume their own body's resources, resulting in liver failure, tachycardia and heart strain. A spokeswoman for the American Dietetic Association stated that, "The bottom line is that even fasting for more than a day can be dangerous. You need food to function." Nutrition researcher Peter Clifton also disagreed with study results, accusing the research team of "cheating" by allowing Jani to gargle and bathe, and stating that a human of average weight would die after "15 to 20 days" without water. People who avoid food and water to emulate mystical figures often die. Sanal Edamaruku characterized the experiment as a farce for allowing Jani to move out of the CCTV cameras' field of view, claiming that video footage showed Jani was allowed to receive devotees and to leave the sealed test room for sunbathing. Edamaruku also said that the gargling and bathing activities were insufficiently monitored. Edamaruku was denied access to the site where the tests were conducted in both 2003 and 2010, and accuses Jani of having "influential protectors" responsible for denying him permission to inspect the project during its operation, despite having been invited to join the test during a live television broadcast. The Indian Rationalist Association observed that individuals making similar claims in the past have been exposed as frauds.
Cretaceous–Paleogene extinction event
In stream communities, few animal groups became extinct because such communities rely less directly on food from living plants and more on detritus washed in from the land, protecting them from extinction. Similar, but more complex patterns have been found in the oceans. Extinction was more severe among animals living in the water column than among animals living on or in the sea floor. Animals in the water column are almost entirely dependent on primary production from living phytoplankton, while animals on the ocean floor always or sometimes feed on detritus. Coccolithophorids and mollusks (including ammonites, rudists, freshwater snails, and mussels), and those organisms whose food chain included these shell builders, became extinct or suffered heavy losses. For example, it is thought that ammonites were the principal food of mosasaurs, a group of giant marine reptiles that became extinct at the boundary. The largest air-breathing survivors of the event, crocodyliforms and champsosaurs, were semi-aquatic and had access to detritus. Modern crocodilians can live as scavengers and survive for months without food, and their young are small, grow slowly, and feed largely on invertebrates and dead organisms for their first few years. These characteristics have been linked to crocodilian survival at the end of the Cretaceous.
Byrrah
He can survive only for 10 minutes out of water, unless he uses a special serum that gives him the ability to breathe air. His stamina, agility, and reflexes are reduced when out of the water.
Infra-Worlders
The Infra-Worlders are a society of humans led by Captain that has lived for five decades in a gigantic submarine named the "Infra-World." These humans have been "evolved" so that their bodies can withstand the water pressure at 5,000 fathoms beneath the ocean's surface; as a result, they cannot live on the surface of the world.
Inhumans
Even without using the Terrigen Mist, the Kree modifications, combined with centuries of selective breeding, have given all Inhumans certain advantages. Their average lifespan is 150 years and an Inhuman in good physical condition possesses strength, reaction time, speed, and endurance greater than the finest of human athletes. Karnak and other normal Inhumans who are in excellent physical shape can lift one ton and are physically slightly superior to the peak of normal human physical achievement. Exposure to the Terrigen Mist can both enhance and in some cases reduce these physical capabilities. Most Inhumans are used to living in a pollution-free, germ-free environment and have difficulty tolerating Earth's current level of air and water pollution for any length of time.
Rock squirrel
They can withstand long periods of time without water, some even up to 100 days.
Water
For those who have healthy kidneys, it is rather difficult to drink too much water, but (especially in warm humid weather and while exercising) it is dangerous to drink too little. People can drink far more water than necessary while exercising, however, putting them at risk of water intoxication (hyperhydration), which can be fatal. The popular claim that "a person should consume eight glasses of water per day" seems to have no real basis in science. Studies have shown that extra water intake, especially up to at mealtime was conducive to weight loss. Adequate fluid intake is helpful in preventing constipation.
An original recommendation for water intake in 1945 by the Food and Nutrition Board of the United States National Research Council read: "An ordinary standard for diverse persons is 1 milliliter for each calorie of food. Most of this quantity is contained in prepared foods." The latest dietary reference intake report by the United States National Research Council in general recommended, based on the median total water intake from US survey data (including food sources): for men and of water total for women, noting that water contained in food provided approximately 19% of total water intake in the survey.
Camel
Camels have a series of physiological adaptations that allow them to withstand long periods of time without any external source of water. The dromedary camel can drink as seldom as once every 10 days even under very hot conditions, and can lose up to 30% of its body mass due to dehydration. Unlike other mammals, camels' red blood cells are oval rather than circular in shape. This facilitates the flow of red blood cells during dehydration and makes them better at withstanding high osmotic variation without rupturing when drinking large amounts of water: a camel can drink of water in three minutes.
Hilton Hotema
In "Man's Higher Consciousness", Hotema wrote that man was designed to live 80,000 to 100,000 years, before his teeth and alimentary canal were subject to degeneration. It was published in 1952 as "Man's Miraculous Unused Power" using the pen name Kenyon Klamonti. George R. Clements (AKA Hilton Hotema, AKA Kenyon Klamonti) claimed he became a vegan at 9 years of age after reading a book about health at school. He said he lived as a breatharian-fruitarian for almost 80 years. He lived to 92 years of age." Hotema is documented in the book "The Struggle Between Religion & Science" by Marshall J. Gauvin.
Food security
Regionally, Sub-Saharan Africa has the largest number of water-stressed countries of any place on the globe, as of an estimated 800 million people who live in Africa, 300 million live in a water-stressed environment. It is estimated that by 2030, 75 million to 250 million people in Africa will be living in areas of high water stress, which will likely displace anywhere between 24 million and 700 million people as conditions become increasingly unlivable. Because the majority of Africa remains dependent on an agricultural lifestyle and 80 to 90 percent of all families in rural Africa rely upon producing their own food, water scarcity translates to a loss of food security.
Cold shock response
Hypothermia from exposure to cold water is not as sudden as is often believed. A person who survives the initial minute of trauma (after falling into icy water), can survive for at least thirty minutes provided they don't drown. However, the ability to perform useful work (for example to save oneself) declines substantially after ten minutes (as the body protectively cuts off blood flow to "non-essential" muscles).