What is Euglena?
Euglena is a type of algae that is considered a novel hybrid between plant and animal: it moves around like an animal, but photosynthesizes like a plant. Euglena's bright green color makes it very visible in water, where it can create "blooms" in areas that have a high concentration of organic waste.
Euglena is a "protist," along with other life forms such as the amoeba and paramecium. These single-celled forms are capable of movement; euglena uses a flagellum to propel itself through the water. However, it also contains green chloroplasts, which convert its food (green algae) into energy.
Euglena Waste Excretion
Euglena has a "contractile vacuole," which it uses to excrete water and waste. The vacuole, like a microscopic bladder, draws in excess water and then pushes it out through a hole in the cell membrane. The hole then recloses, and euglena's cell is again complete and free of waste. This type of waste excretion system is found in other types of protists, including paramecium.
Euglena and Pollution
Euglena likes to feed on green algae, which grows in waters with high nitrogen levels. As waste accumulates in the water, green algae grows; this can attract vast numbers of euglena, resulting in bright green "blooms" that color both water and beaches. Although euglena is microscopic and invisible to the naked eye, when it appears in vast numbers it can be seen as a green, slimy film that forms on any wet surface and on the surface of water. Euglena blooms look much like the algae they consume, but this is only because the algae's color is visible in their "bodies" even as they consume it.
Scientists are researching the possible use of euglena as a pollution indicator: it may be an effective way of discovering polluted water and of following water runoff. However, although euglena is found in polluted areas, it does not consume waste and pollution.
It may also be possible to apply euglena to exhaust emissions from factories and industrial plants: it can be grown under very high concentrations of carbon dioxide, and may be able to reduce carbon dioxide levels in emissions.