The source of the microorganisms
Typically, these contaminants can come from wastewater, surrounding animal activities or animal carcasses. Wastewater includes sewage, industrial water that may contain organic contaminants and any other water that has been used for human activities.
Wildlife activities can promote the formation of microorganisms in the water, mainly due to defecation along the edges of water bodies that could accumulate in the water.
The risks associated with their presence
The presence of microorganisms in water can create several problems to it. These include colour, odour and taste. However, the risks to be considered are those associated with the consumption of contaminated water. First, the presence of microorganisms in water suggests the presence of pathogens. Drinking water containing pathogens can lead to problems such as diarrhea, vomiting, cramps, nausea, headaches, intense fatigue and even death.
Types of microorganisms
Simply put, microorganisms fall into 7 categories:
- Bacteria;
- Archaea;
- Protozoa;
- Algae;
- Fungi;
- Viruses; and
- Multicellular animal parasites
Techniques for Their Removal
Effective treatment methods for these types of contaminants are generally known as disinfection methods. These include chemical disinfection techniques, physical disinfection techniques and physical-chemical disinfection techniques.
Among the most widespread disinfection technologies, we find the following.
- Chlorination: consists of adding chlorine or chlorine derivatives to the water to eliminate microorganisms.
- Ultraviolet irradiation: it consists of the emission of ultraviolet rays to alter the DNA of microorganisms in order to prevent their proliferation.
- Ozonation: similar to chlorination, ozonation consists of the addition of ozone as an oxidizing product to eliminate microorganisms.
Even if there are other techniques for the treatment of microorganisms, the three mentioned above are undoubtedly the most widespread and used.