Bacteria Discovery Kit, available from our partner.What kinds of reactive oxygen species are created during the irradiation of oxygenated water with UVA? How do these reactive oxygen species contribute to the disinfection process?.What is the technical difference between sterilization and disinfection? Is SODIS a sterilization or a disinfection procedure?.Is SODIS just as effective with glass bottles as it is with clear plastic PET bottles?.In which parts of the world is SODIS used?.In doing this science fair project, you can become a part of that mission. One of the missions of science research is to help improve human health and life. You will test different exposure times and compare the results to boiling water.
In this microbiology science fair project, you will investigate the exposure time to UVA light that is required for a bottle of water to be disinfected. If the temperature of the water rises above 50☌, the disinfection process proceeds three times faster. The IR portion of the spectrum heats the water. The UVA reacts with the oxygen dissolved in the water and produces highly reactive forms of oxygen that are thought to kill pathogens in the water by causing fatal DNA damage and destroying the cell walls of bacteria. The UV spectrum is also separated into several portions, one of which is UVA, which has a spectrum of 320 nm–400 nm. So what exactly does the sunlight do to the organisms in the water, making it safe to drink? Light from the Sun can be separated into several sections, three of which are as follows: visible light (400–700 nanometers (nm)), ultraviolet (UV) light (10 nm–400nm), and infrared (IR) light (700 nm–1 millimeter (mm)). After a certain amount of time (which you'll be investigating in this science fair project), the water will be ready to drink. Place the bottle on a black iron sheet or on your roof, where it will have access to sunlight. Now fill the bottle fully and close the lid. Shake the bottle for 20 seconds to aerate it. Highly turbid water protects the pathogens from the Sun's radiation. PET bottles are recyclable and have a "1" surrounded by a triangle symbol on the bottom.
The first step is to find a PET bottle with a lid and clean it well.
#Oxygen not included disinfect water free
This process takes advantage of sunlight, which is free and readily available, and plastic polyethylene terephthalate (PET) bottles, which are available around the world. In this situation, there is a water-disinfection procedure that is available, solar disinfection, also known as SODIS. Fuel for boiling water might not even be available. However, there are significant safety issues when using these chemicals.īut what if you live in an undeveloped nation? You might not have the financial resources available to purchase chemicals. Both iodine tinctures and calcium hypochlorite are better at treating contaminated water than bleach is. If the water is cloudy before you've chemically treated it, then double the number of bleach drops and double the amount of time that it stands. Add two drops of bleach for every quart or liter of water, stir or shake the water, and then let it stand for at least 30 minutes. To treat the water chemically, first filter the water and then use regular, unscented household bleach. Let the water cool, and then transfer it to a clean container. According to the Environmental Protection Agency (EPA), the best way to disinfect water is to first filter the water and then boil it vigorously for 1–3 minutes. These pathogens can be present in water anywhere. In fact, more than 1.5 million children under the age of 5 years die each year of water-borne diseases in Africa and Asia. Often, when a person who doesn't have access to good health care contracts one of these diseases, it can be fatal. These include Vibrio cholerae (a bacteria that results in cholera), Shigella dysenteriae (a bacteria that causes dysentery), Giardia lamblia (a parasite that results in giardia), and viruses like polio. Water can be contaminated with several types of water-borne pathogens. The lack of safe water can be due to drought, war, or perhaps a town doesn't have the money or infrastructure to provide clean water to its citizens. The United Nations International Children's Emergency Fund (UNICEF) and the World Health Organization (WHO) estimate that 1 billion people do not have access to safe drinking water. However, there are people that don't have the luxury of clean and safe water. Our towns and cities provide us with clean and safe drinking water because they have the means and infrastructures to clean and disinfect water. You probably go about your day without giving your abundant and clean water a second thought. Water is necessary for growing plants, many of which produce food for us.