Coliform bacteria are always present in the digestive tract of animals and humans, as well as in their waste products. They can also be found on plants, soil and water, where contamination is a major problem due to the possibility of contracting diseases caused by various pathogens.
Harm to the body
Are coliform bacteria harmful? Most of them do not cause disease, however, some rare strains of E. coli can cause serious illness. In addition to humans, sheep and cattle may also be infected. It is worrying that contaminated water, in its external characteristics, is no different from ordinary drinking water in taste, smell and appearance. Coliform bacteria are found even in well water, which is considered to be impeccable in every sense. Testing is the only reliable way to find out about the presence of disease-causing bacteria.
Whathappens upon detection?
What to do if coliform bacteria or any other bacteria are found in drinking water? In this case, repair or modification of the water supply system will be required. When used for disinfection, a mandatory boil is provided, as well as retesting, which can confirm that the contamination was not eliminated if it was thermotolerant coliform bacteria.
Indicator organisms
Common coliforms are often referred to as indicator organisms because they indicate the potential presence of pathogenic bacteria in water, such as E. coli. While most strains are harmless and live in the intestines of he althy humans and animals, some can produce toxins, cause serious illness, and even death. If pathogenic bacteria are present in the body, the most common symptoms are gastrointestinal upset, fever, abdominal pain, and diarrhea. Symptoms are more pronounced in children or older family members.
Safe water
If there are no common coliform bacteria in the water, then with almost certainty it can be assumed that it is microbiologically safe to drink.
If they were found, then additional tests would be justified.
Bacteria love warmth andmoisture
Temperature and weather conditions also play an important role. For example, E. coli prefers to live on the surface of the earth and loves warmth, thus coliform bacteria in drinking water appear as a result of movement in underground streams during warm and humid weather conditions, while the smallest number of bacteria will be found in the winter season.
Impact chlorination
For the effective destruction of bacteria, chlorine is used, which oxidizes all impurities. Its amount will be affected by water characteristics such as pH and temperature. On average, the dry matter weight per liter is approximately 0.3-0.5 milligrams. It takes approximately 30 minutes to kill common coliform bacteria in drinking water. Contact time can be reduced by increasing the dose of chlorine, but this may require additional filters to remove specific tastes and odors.
Destructive ultraviolet light
UV rays are considered a popular disinfection option. This method does not involve the use of any chemical compounds. However, this agent is not used where the total coliform bacteria exceed one thousand colonies per 100 ml of water. The device itself consists of a UV lamp surrounded by a sleeve of quartz glass through which a liquid flows, irradiated with ultraviolet light. Raw water inside the machine must be completely clean and freefrom any visible contamination, blockage or turbidity to allow exposure of all harmful organisms.
Other cleaning options
There are many other treatments used to disinfect water. However, they are not recommended as long term for various reasons.
- Boiling. At 100 degrees Celsius for one minute, bacteria are effectively killed. This method is often used to disinfect water during emergencies or when needed. This takes time and is an energy intensive process and is generally only applied in small amounts of water. This is not a long-term or permanent option for water disinfection.
- Ozonation. In recent years, this method has been used as a way to improve water quality, eliminate various problems, including bacterial contamination. Like chlorine, ozone is a strong oxidizing agent that kills bacteria. But at the same time, this gas is unstable, and it can only be obtained with the help of electricity. Ozone units are generally not recommended for disinfection because they are much more expensive than chlorination or UV systems.
- Iodine. The once popular method of disinfection is now recommended only for short-term or emergency disinfection of water.
Thermotolerant coliform bacteria
This is a special group of living organisms that are able to ferment lactose when44-45 degrees Celsius. These include the genus Escherichia and some species of Klebsiella, Enterobacter and Citrobacter. If foreign organisms are present in the water, this indicates that it has not been sufficiently cleaned, re-contaminated, or contains nutrients in excess. If they are found, it is necessary to check for the presence of coliform bacteria that are resistant to elevated temperatures.
Microbiological analysis
Coliform organisms belong to a class of gram-negative bacteria that look like rods, they live and reproduce in the lower digestive tract of animals and humans. In general, bacteria include many varieties that are dangerous to one degree or another. Microbiological analysis also includes the identification of various viruses and parasites. Microbiological analysis is carried out not only to test drinking water, but also to check the safety of those water bodies where people enjoy spending their leisure time. Some, of course, are not afraid of swimming in the water where the "stick" was found, but the safety of such water is also regulated. There are certain hygienic requirements for the condition of surface waters.
If coliforms were found, this may indicate that pathogenic microorganisms have entered the water. Thus, various diseases begin to spread. In contaminated drinking water, strains of Salmonella, Shigella, Escherichia coli and many other pathogens can be found.range from mild digestive disorders to the most severe forms of dysentery, cholera, typhoid fever and many others.
Domestic sources of infection
The quality of drinking water is monitored, it is regularly checked by specialized sanitary services. And what can an ordinary person do to protect himself and protect himself from unwanted infection? What are the sources of domestic water pollution?
- Water from the cooler. The more people touch this device, the more likely it is that harmful bacteria will enter. Studies show that the water in every third cooler is simply teeming with living organisms.
- Rainwater. Surprisingly, the moisture collected after rain is a favorable environment for the development of coliform bacteria. Advanced gardeners don't even use this water to water their plants.
- Lakes and reservoirs are also at risk, since all living organisms multiply faster in stagnant water, and not just bacteria. The only exception is the oceans, where the development and spread of harmful forms is minimal.
- Pipeline condition. If the sewers have not been changed and cleaned for a long time, this can also lead to trouble.
