Ancient Age

The oldest antecedents are found in Mesopotamia and date back to the fourth millennium BC. C. when clay pipes, sewers and toilets were invented. In the city of Uruk, the first internal pit toilet was found, dating back to 3,200 BC. C.[7]​.

In the Neolithic village of Skara Brae, in Scotland, small internal rooms with a common drain were found around 3,000 BC. C.[8]​.

It was the Indus Valley civilization in northwest India and Pakistan that hosted the first known urban sanitation systems in the world. In Mohenjo-Daro (2800 BC), toilets were built on the outer walls of houses, which had vertical pipes through which waste was evacuated to cesspools or sewers. It was discharged into nearby bodies of water or into cesspools, which were emptied and cleaned periodically.[10]​.

The oldest latrine in the region was found in Southeast Asia. At the archaeological site of Rạch Núi"), in southern Vietnam, during the excavation of a Neolithic village, a toilet dated to 1500 BC was found. The excavation also provided important clues about the primitive society of Southeast Asia, as more than 30 coprolites were found, which contained fish and destroyed animal bones, providing information on the diet of humans and dogs, and on the types of parasites. that they carried.[11]​.

The city of Rome once had more than a million inhabitants. Rome had an extensive underground drainage system.[12]​ In the center of Rome there were 144 public latrines, although the number of seats in each of them is not known.[13]​ The Romans distinguished between individual "vateres" (latrinae) and collective ones (foricae). The action of defecating was not an intimate act, but something that was done in public, sharing talk and jokes, and even a finished stick in a sponge that they used to clean themselves.[14]​ In Roman civilization, running water latrines were sometimes part of public baths. Roman toilets were located above open sewers that were periodically "flushed" with running water. The Romans and Greeks also used chamber pots, which they took to meals and drinking sessions.[15]​.

In Pompeii, public and private latrines emptied their water into cesspools that were located under the sidewalks. Although there were many public latrines, the toilets also began to be moved to the upper floors of the insulae in a trend towards isolating the latrine within the building, making it, increasingly, a single space. Over time, they also moved from wooden seats to stone ones. The Romans knew certain repellents, such as a mixture of coriander and olive oil, or sometimes they had a slave fan the flies.[12] A team of British anthropologists investigated hundreds of bags of human excrement from Herculaneum and found in an 86 m long tunnel. The 774 bags provided a lot of information about the diet of the Romans, who ate a large amount of vegetables and a great diversity of foods: from sea urchins and dormice to fish, figs, olives and eggs.[16]​.

Middle Ages

In Sri Lanka, toilet and washbasin construction techniques developed over several stages. At the Abhayagiri complex in Anuradhapura, toilets and baths are known to date back to the centuries BC. C. to d. C. At Polonnaruwa and Anuradhapura, toilets from the century AD. C. al they had elaborate decorative motifs carved around them. Various types of toilets were developed; among them, sinks with annular wells, underground terracotta pipes leading to septic tanks, urinary pits with large bottomless clay vessels of decreasing size placed one on top of the other. These vessels under the urinals contained "sand, lime and charcoal" through which the urine was filtered to the ground in a purification process.[17]​.

Quevedo, in a scene from Buscón called Don Pablos, indicates the use of the "service" to evacuate. This consisted of a kind of potty that collected excrement or urine and was emptied directly onto the public street with the prior notice: "Water is coming!"[18] The cabin or room where the potties were kept was also called "service", which would later be called "toilet".

John Harington described in 1596 a predecessor of the toilet that was emptied using a valve.

The hydraulic closure system with a siphon, or S-shaped tube, was patented by Alexander Cumming in 1775.

The peculiarity of the water toilet is that it has an angled drain, so that water is retained in it, forming a hydraulic seal or siphon, which prevents the passage of unpleasant odors. The removal of organic matter to sanitation requires a device that produces a discharge of a large flow of water in a very short time, leaving nothing but clean water in the elbow of the hydraulic seal. This device can be a cistern or a special valve called a flushometer.

The cisterns, which can be high (fixed to the wall at a height of almost two meters) or low, have a filling mechanism, with a level valve, which cuts off the water inlet when it reaches a certain level, and a discharge mechanism, activated by the user. Due to its position, the tall cistern requires less water to operate.

In some public toilets and hotels, to avoid vandalism, built-in cisterns are used behind the wall that supports the toilet, located higher than the low cistern and lower than the high cistern, so that only the activation button is visible from the cistern, being large enough to serve as a cistern register for repairs.

In collective toilets, where the frequency of use may be high, flushometers are used, which avoid having to wait the time necessary to fill the cistern between one use and the next. However, the use of this device should be limited, because it requires larger diameter pipes and, if the installation has many devices of this type connected, it may require its own installation, different from the normal one. On the contrary, it has the advantage, in collective public toilets, that it is more difficult to damage it due to vandalism.

The different categories of toilets include:.

The pedestal toilet is designed so that the person using it can do so in a sitting position for both defecation and urination. Therefore, it has a height of around 40 cm (centimeters) and a special plate to support the thighs comfortably.

However, it is traditional for men to use it in a standing position to urinate, using their penis to guide the urine into the device. There are opinions that question this use by men: most of the advice to teach children to use the device[22]​ and the proposals of some politicians. According to these proposals, the reasons for encouraging the use of the toilet in a sitting position in men are to have "bathrooms clean of puddles and splashes" and the fact that in this position the bladder is evacuated more effectively and reduces the risk of prostate problems. Proposals of this type have been made by Viggo Hansen of the Swedish Left Party[23][24]​ and the Taiwanese minister Stephen Shen.[25]​ The device designed for urinating in a standing position is the urinal.

When someone decides to use the toilet, they are inevitably contaminating the water. It is estimated that a family of five that uses it contaminates more than 150,000 L (liters) of water by transporting about 250 kg (kilograms) of feces and 2,500 L of urine in a year.

Wastewater treatment plants (WWTP) can help minimize the negative environmental impact that this can have, reducing the spread of infectious diseases (such as gastroenteritis and cholera, among others), but, in 90% of cases in the world, wastewater does not receive treatment and goes directly into the environment.[26]​ In addition, there are many types of drugs and other chemicals that cannot be reliably eliminated in WWTPs.[27]​.

The provision of toilets as part of sanitation interventions contributes to improving health and social development outcomes. A review of various studies conducted in Africa, Asia and Latin America concluded that sanitation and hygiene interventions reduce the risk of diarrhea, leading to a decrease in morbidity of 37% on average.[28]​.

Some experts suggest that the Western toilet, which is the most widespread today, is poorly designed, since it forces the user to sit down to defecate. Apparently, this position is not the most efficient or the most hygienic to fulfill this physiological need, given that the human organism has not evolved to defecate in a sitting position, but rather in a squatting position, like other primates.[29]​[30]​ Defecating sitting involves a greater expenditure of body oxygen, especially in asthmatics or the elderly with respiratory diseases and they may become deficient in oxygen by having to support their own weight. The solution is to defecate in a squatting position, but body is supported by an ergonomic seat.

The field of ecological sanitation offers other ways to treat excreta, without contaminating the environment and taking advantage of the material as a valuable resource. There are dry ecological toilets with urine separation and dry toilets that use absorbent material instead of water. ArborLoo are very economical and allow the land where trees are to be planted to be fertilized, instead of generating sewage that pollutes rivers and seas.

Ancient Age

The oldest antecedents are found in Mesopotamia and date back to the fourth millennium BC. C. when clay pipes, sewers and toilets were invented. In the city of Uruk, the first internal pit toilet was found, dating back to 3,200 BC. C.[7]​.

In the Neolithic village of Skara Brae, in Scotland, small internal rooms with a common drain were found around 3,000 BC. C.[8]​.

It was the Indus Valley civilization in northwest India and Pakistan that hosted the first known urban sanitation systems in the world. In Mohenjo-Daro (2800 BC), toilets were built on the outer walls of houses, which had vertical pipes through which waste was evacuated to cesspools or sewers. It was discharged into nearby bodies of water or into cesspools, which were emptied and cleaned periodically.[10]​.

The oldest latrine in the region was found in Southeast Asia. At the archaeological site of Rạch Núi"), in southern Vietnam, during the excavation of a Neolithic village, a toilet dated to 1500 BC was found. The excavation also provided important clues about the primitive society of Southeast Asia, as more than 30 coprolites were found, which contained fish and destroyed animal bones, providing information on the diet of humans and dogs, and on the types of parasites. that they carried.[11]​.

The city of Rome once had more than a million inhabitants. Rome had an extensive underground drainage system.[12]​ In the center of Rome there were 144 public latrines, although the number of seats in each of them is not known.[13]​ The Romans distinguished between individual "vateres" (latrinae) and collective ones (foricae). The action of defecating was not an intimate act, but something that was done in public, sharing talk and jokes, and even a finished stick in a sponge that they used to clean themselves.[14]​ In Roman civilization, running water latrines were sometimes part of public baths. Roman toilets were located above open sewers that were periodically "flushed" with running water. The Romans and Greeks also used chamber pots, which they took to meals and drinking sessions.[15]​.

In Pompeii, public and private latrines emptied their water into cesspools that were located under the sidewalks. Although there were many public latrines, the toilets also began to be moved to the upper floors of the insulae in a trend towards isolating the latrine within the building, making it, increasingly, a single space. Over time, they also moved from wooden seats to stone ones. The Romans knew certain repellents, such as a mixture of coriander and olive oil, or sometimes they had a slave fan the flies.[12] A team of British anthropologists investigated hundreds of bags of human excrement from Herculaneum and found in an 86 m long tunnel. The 774 bags provided a lot of information about the diet of the Romans, who ate a large amount of vegetables and a great diversity of foods: from sea urchins and dormice to fish, figs, olives and eggs.[16]​.

Middle Ages

In Sri Lanka, toilet and washbasin construction techniques developed over several stages. At the Abhayagiri complex in Anuradhapura, toilets and baths are known to date back to the centuries BC. C. to d. C. At Polonnaruwa and Anuradhapura, toilets from the century AD. C. al they had elaborate decorative motifs carved around them. Various types of toilets were developed; among them, sinks with annular wells, underground terracotta pipes leading to septic tanks, urinary pits with large bottomless clay vessels of decreasing size placed one on top of the other. These vessels under the urinals contained "sand, lime and charcoal" through which the urine was filtered to the ground in a purification process.[17]​.

Quevedo, in a scene from Buscón called Don Pablos, indicates the use of the "service" to evacuate. This consisted of a kind of potty that collected excrement or urine and was emptied directly onto the public street with the prior notice: "Water is coming!"[18] The cabin or room where the potties were kept was also called "service", which would later be called "toilet".

John Harington described in 1596 a predecessor of the toilet that was emptied using a valve.

The hydraulic closure system with a siphon, or S-shaped tube, was patented by Alexander Cumming in 1775.

The peculiarity of the water toilet is that it has an angled drain, so that water is retained in it, forming a hydraulic seal or siphon, which prevents the passage of unpleasant odors. The removal of organic matter to sanitation requires a device that produces a discharge of a large flow of water in a very short time, leaving nothing but clean water in the elbow of the hydraulic seal. This device can be a cistern or a special valve called a flushometer.

The cisterns, which can be high (fixed to the wall at a height of almost two meters) or low, have a filling mechanism, with a level valve, which cuts off the water inlet when it reaches a certain level, and a discharge mechanism, activated by the user. Due to its position, the tall cistern requires less water to operate.

In some public toilets and hotels, to avoid vandalism, built-in cisterns are used behind the wall that supports the toilet, located higher than the low cistern and lower than the high cistern, so that only the activation button is visible from the cistern, being large enough to serve as a cistern register for repairs.

In collective toilets, where the frequency of use may be high, flushometers are used, which avoid having to wait the time necessary to fill the cistern between one use and the next. However, the use of this device should be limited, because it requires larger diameter pipes and, if the installation has many devices of this type connected, it may require its own installation, different from the normal one. On the contrary, it has the advantage, in collective public toilets, that it is more difficult to damage it due to vandalism.

The different categories of toilets include:.

The pedestal toilet is designed so that the person using it can do so in a sitting position for both defecation and urination. Therefore, it has a height of around 40 cm (centimeters) and a special plate to support the thighs comfortably.

However, it is traditional for men to use it in a standing position to urinate, using their penis to guide the urine into the device. There are opinions that question this use by men: most of the advice to teach children to use the device[22]​ and the proposals of some politicians. According to these proposals, the reasons for encouraging the use of the toilet in a sitting position in men are to have "bathrooms clean of puddles and splashes" and the fact that in this position the bladder is evacuated more effectively and reduces the risk of prostate problems. Proposals of this type have been made by Viggo Hansen of the Swedish Left Party[23][24]​ and the Taiwanese minister Stephen Shen.[25]​ The device designed for urinating in a standing position is the urinal.

When someone decides to use the toilet, they are inevitably contaminating the water. It is estimated that a family of five that uses it contaminates more than 150,000 L (liters) of water by transporting about 250 kg (kilograms) of feces and 2,500 L of urine in a year.

Wastewater treatment plants (WWTP) can help minimize the negative environmental impact that this can have, reducing the spread of infectious diseases (such as gastroenteritis and cholera, among others), but, in 90% of cases in the world, wastewater does not receive treatment and goes directly into the environment.[26]​ In addition, there are many types of drugs and other chemicals that cannot be reliably eliminated in WWTPs.[27]​.

The provision of toilets as part of sanitation interventions contributes to improving health and social development outcomes. A review of various studies conducted in Africa, Asia and Latin America concluded that sanitation and hygiene interventions reduce the risk of diarrhea, leading to a decrease in morbidity of 37% on average.[28]​.

Some experts suggest that the Western toilet, which is the most widespread today, is poorly designed, since it forces the user to sit down to defecate. Apparently, this position is not the most efficient or the most hygienic to fulfill this physiological need, given that the human organism has not evolved to defecate in a sitting position, but rather in a squatting position, like other primates.[29]​[30]​ Defecating sitting involves a greater expenditure of body oxygen, especially in asthmatics or the elderly with respiratory diseases and they may become deficient in oxygen by having to support their own weight. The solution is to defecate in a squatting position, but body is supported by an ergonomic seat.

The field of ecological sanitation offers other ways to treat excreta, without contaminating the environment and taking advantage of the material as a valuable resource. There are dry ecological toilets with urine separation and dry toilets that use absorbent material instead of water. ArborLoo are very economical and allow the land where trees are to be planted to be fertilized, instead of generating sewage that pollutes rivers and seas.