Protozoa

Protozoa are single-celled microorganisms that belong to the kingdom Protista, which are a diverse group of eukaryotic microorganisms that can be found in various aquatic environments, including freshwater and marine ecosystems. Some protozoa are free-living, while others can be parasites, that play essential roles in nutrient cycling that are often found in sediments, on submerged surfaces, and in the water column itself. They’re known to thrive in a wide range of aquatic habitats, including lakes, rivers, ponds, oceans and even in moist soil, found in both freshwater and saltwater environments. Protozoa are primarily heterotrophic, which means they obtain their nutrition by consuming other microorganisms, organic matter, and particulate material present in water. Some protozoa are free-living, while others can be parasitic, causing diseases in humans and other animals and posing health risks, with examples such as pathogenic protozoa include Giardia and Cryptosporidium, which can cause gastrointestinal illnesses when ingested via contaminated water. Water treatment processes, including filtration and disinfection, are designed to remove or inactive pathogenic protozoa from drinking water to ensure its safely for consumption.