Japan's century-old hot spring hotel was exposed that it did not change water for half a year! How to "soak in the bath" healthily?

Written by/Reporter Zhao Tianyu Graphic Editor/Chen Yongjie

New Media Editor/Lv Bingxin

Interview with experts:

GAO Jianwei (Senior Engineer, Physical Geological Data Center, China Geological Survey)

Zheng Kedi (Director of the Expert Committee of China Geothermal Industry Working Committee)

Cheng Jiqun (Deputy Chief Physician, Department of Dermatology, Third Medical Center, PLA General Hospital)

Recently, a century-old hot spring hotel in Japan appeared on Weibo hot search, because it was exposed that the water had not been changed for half a year.

According to CCTV financial news, a few days ago, a century-old hot spring hotel in Japan was exposed to a scandal, it turned out that in this long-established hotel, the hot spring water that should have been changed once a week was only changed once every half a year, resulting in legionella exceeding the standard by 3,700 times, and guests have been infected and treated for medical treatment.

Soaking in hot springs has become more and more popular choice, not only to reduce physical fatigue, but also to relieve mental stress, especially for people living and working in the city, it is a good way to relax and well. However, with the "generalization" of the concept of hot springs today, some fake hot springs have also begun to confuse the public and fill up indiscriminately, causing a lot of losses to consumers. What water can be called a hot spring? How to distinguish a "fake hot spring"? What are the precautions for ordinary people to soak in hot springs?

Explore:

What exactly is "hot spring water"?

What exactly is a "hot spring"? In fact, so far, the mainland does not have an authoritative, official definition of "hot spring".

Gao Jianwei, senior engineer of the Physical Geological Data Center of the China Geological Survey, told reporters that hot springs are a valuable and multi-purpose hydrothermal geothermal resource. Only mineral water that springs naturally from underground holes or fissures, exceeds 25°C (or the spring mouth is 5°C higher than the local average temperature), and contains trace elements that are beneficial to human health, can be called hot spring water.

The causes of hot springs vary depending on the natural environment and geological conditions, but simply put, they can be summarized into two categories: sulfurous hot spring water formed by magma action (or volcanic action) inside the earth's crust, and carbonated hot spring water formed by surface water infiltrating into the formation. However, both types of hot springs have prerequisites: geothermal heat is necessary here for the hot springs to occur.

▲Outdoor hot spring (Image source: Visual China)

Gao Jianwei explained that due to plate movement, some places of tectonic, magmatic activity (including volcanic eruptions) are more frequent, if the crustal plate movement causes the surface to rise, there is uncooled magma below, it will continue to release heat to become a heat source, at this time if there are water-bearing rock layers in the nearby pores, the heated water will surge up, and then form hot springs. This kind of hot spring mostly occurs in areas where geological movements are more intense, and the Yangbajing Hot Spring in Tibet located on the Qinghai-Tibet Plateau is a typical representative.

The other is a hot spring formed by the infiltration cycle of surface water. The principle is that in some areas, rainwater and other surface water seep into the aquifer inside the earth's crust, and then form groundwater. Groundwater is heated by the geothermal heat below to become hot water, if there is a dense and airtight rock layer above the groundwater, the groundwater and gas will be "locked" inside, the pressure is increasing, and once there is a crack in the rock formation above, the groundwater will gush out.

Due to the large static pressure difference required, this type of hot spring is more common in valleys, such as Chengde City, Hebei Province, located in the valley of the Yanshan Mountains, which was also called "hot river" in the past because of the abundant geothermal water resources.

▲Schematic diagram of hot spring formation (Drawing: Wang Xueying)

However, in recent years, with the large-scale tourism development, the concept of hot springs has long been generalized. Zheng Keji, director of the Expert Committee of the China Geothermal Industry Working Committee, pointed out that in addition to the hot spring water that flows out naturally, geothermal water with a water temperature higher than 25°C is extracted through underground wells; Geothermal water that is heated and pressurized at the outlet of the water is called hot spring water.

It is also in the context of this standard generalization that the current hot spring industry has been "mixed", coupled with the uneven distribution of geothermal resources in the mainland, and even the emergence of indiscriminate "fake hot springs", so that "hot springs" become "high-priced baths", losing its own meaning.

Anti-counterfeiting:

How to identify the "lee ghost" in the hot spring

In addition to natural hot springs, there are currently many artificial hot springs in China, which are drilled and drilled wells to extract hot spring water from deep fault zones. Zheng Keji said that this kind of hot spring is also called a hot spring well, the water temperature can reach more than 25 °C, because it is artificially mined, so it cannot be called a natural hot spring, can only be called "hot spring" or "artificial hot spring".

However, many hot spring wells outlet temperature is low, coupled with the large loss of water temperature in the process of transporting hot springs, can not meet the requirements of customers, need to use heat exchanger to keep warm up, that is, in the transportation process or outlet heating, this kind of hot spring is called warming hot spring, is an artificial method to make up for temperature loss.

As long as the outlet temperature and trace elements meet the standards, hot springs that have only undergone heat exchange without water exchange can also be counted as qualified. But some behaviors that make a fuss about "water" are naked "counterfeit products".

Gao Jianwei said that some hot spring water comes from the surface, "heats" along pipes laid from the ground and then returns to the ground, giving people the illusion of underground hot spring water; In some areas, the amount of groundwater is insufficient, so the hot spring water is repeatedly heated and recycled. This type of hot spring is very impure and very different from naturally occurring hot springs, and the effect is greatly reduced.

▲Consumers should be able to distinguish which are fake hot springs (Image source: Visual China)

What's more, some scenic spots or merchants that do not have hot spring conditions at all, in order to attract consumers, add sulfur powder mixed with artificial hot water to impersonate hot spring water, so as to achieve the purpose of fake reality. According to people familiar with the matter, the price of sulfur powder is not high, the price per catty is only 4-6 yuan, but 1 kilogram of sulfur powder brewed hot spring water is enough for a 40-square-meter pool, which can be regarded as a "high-yield product".

For many consumers, the greatest attraction of hot springs is their curative effect. Therefore, hot spring companies spared no expense in publicity. "Contains a variety of minerals and trace elements that are beneficial to the human body, beauty and beauty, strengthens the body, can treat arthritis, skin diseases..."

How can ordinary consumers distinguish between real and fake hot spring water? Zheng Kedi said that the simplest is to judge by the state after soaking: the real hot spring water comes from the deep surface of the earth, contains a large amount of sodium, belongs to soft water, people can feel a slight buoyancy during the soaking process, and the skin has a smooth feeling after soaking. On the contrary, fake hot spring water is hard water, mainly composed of calcium, and the skin will turn white and appear folded after soaking.

You can also tell the difference between real and fake hot springs by region. According to the data, mainland hot springs are mainly distributed in Tibet, Yunnan, Taiwan, Guangdong and Fujian, accounting for more than 50% of the total number of hot springs in the country, followed by Liaoning, Shandong, Jiangxi, Hunan, Hubei and Sichuan. Geothermal resources are mainly distributed in tectonic activity zones and large sedimentary basins, the former of which are more concentrated, such as Tibet, Yunnan and Sichuan areas, the southeast coastal belt and the Liaodong-Jiaodong area. The latter resources are widely distributed, such as the Beijing-Tianjin-Tang region of the North China Basin. "The northwest region of the mainland, the Loess Plateau, the Huanghuai region and the Yangtze River Delta region are not rich in geothermal resources, especially the Loess Plateau." Gao Jianwei said.

Focus on health:

Who is not suitable for hot springs?

Many people like to soak in hot springs for more than half a day, but they do not know that such a practice is likely to "oversoak", or even cause physical discomfort and suffer from "hot spring disease".

In fact, according to the different components contained in the water, hot springs can be divided into acidic springs, alkaline springs and neutral springs: acidic hot springs can promote blood circulation, improve blood vessel function, and have a certain bactericidal effect, but are not suitable for patients with kidney disease and people with poor stomach. Alkaline springs have a certain effect on skin diseases, rheumatism, and arthritis, but the "side effects" are also more obvious, and they are not very friendly to people with skin allergies, and it is easy to "exert too much force".

▲Hot spring is a kind of leisure that citizens love in winter (Image source: Visual China)

Especially the most common sulfur hot springs in alkaline springs, Cheng Jiqun, deputy chief physician of the Department of Dermatology of the Third Medical Center of the PLA General Hospital, told reporters that if the sulfur hot spring is too long, the sulfur component is easy to irritate the skin, coupled with the natural hot springs around the big city itself is not much, artificial sulfur hot springs are easy to cause the skin to dry out. If you scrub continuously, the protective layer of the skin is severely damaged and it will become more dry and itchy.

"Even some people with a bad skin foundation, such as people who are prone to allergies, will suffer from dry dermatitis, scratching the skin and causing an infection that can easily cause a rash, resulting in folliculitis, which is more common clinically." Cheng Jiqun said.

Some people, because of high water temperature and accelerated blood circulation, may experience symptoms such as chest tightness, palpitation, shortness of breath, dizziness, and even increase blood pressure in some patients with underlying cardiovascular diseases, resulting in physical discomfort in a short period of time. Cheng Jiqun suggested that patients in the acute onset of various diseases, patients with underlying skin diseases, elderly people with chronic diseases such as high blood pressure, diabetes, heart disease, and children who are not yet adults are not suitable for hot springs.

"Especially in the northern region, the winter climate itself is relatively dry, ordinary people soaking in hot springs for a long time can easily cause skin diseases, or follow the principle of moderate and moderate amount, and do a good job of moisturizing after soaking in hot springs." If possible, try to go to a high-star hot spring club, or a hot spring with better sanitation and water quality, which can also reduce the probability of 'hot spring disease'. Cheng Jiqun said.

Produced by: Popular Science Central Kitchen

Executive Producer: Beijing Science and Technology News | Beike Media

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