Description: The first testing was MPN in 1908, then use of membrane filtration system in 1950. Currently there are enzyme testing, rapid microbial detection and home water testing kits.
History of Water Testing
Water testing dates back as early as 1908. During this time period the most common water testing was most probable number (MPN). This testing was also called the multiple tube or dilution tube method. This test uses multiple sample tubes that has a growth media (organism) added to the tubes, they are then introverted and observed for gas formation. This gas formation is an indicator of coliform. Then, based on the number of tubes that had a reaction, a probable number was calculated. This test had flaws such as providing false positives.
In the 1950s the membrane filtration method was introduced. This test filters water through a membrane. If there are any bacteria it would be located on the surface of the filter. The filter is then placed in a petri dish and analyzed within 24 hours. Using a microscope, coliform was detected and counted. There was a drawback; other bacteria could over take the filter and the coliform could not be located or counted.
In the 1990s new water testing became available. Three enzyme tests were approved and they are more reliable as they change color when the water tests positive when coliform bacteria is present. These three enzymes included: Coliert, Coliert-18 and Colisure. These enzyme tests still take 18 to 24 hours for an incubation period. The water sample is then run through an UV light. The water will change color depending on the enzyme being used in the testing. Like other testing methods there are some drawbacks, this includes that the results can be subjective. Not all colors are clear change depending on bacteria in the water. The observer can make a mistake in determining coliform bacteria in the water.
In 2014 the Tecta Rapid Microbial detection was approved. This takes all the guess work out of testing public water. Using a special bottle, it separates the organisms into the bottom of the container. A colored florescent light reacts to the organisms. Depending on the level of contamination and what the contamination is, the test results can be provided in 2 to 10 hours.
Testing with AquaKnow
Water testing for your home has improved over the last few years. If you think that your water is contaminated, AquaKnow has residential and business water testing kits available. There are a variety of kits for city water, well water and even test for pesticides. One of the common testing kits available is the City Water Deluxe testing kit. This tests for heavy metals, disinfectants, chemicals and radiological concerns.
If your water is cloudy, has a strange taste or you begin to have skin irritation, don’t take unnecessary chances. Get your water tested. AquaKnow provides fast, reliable affordable tests. For more information on water testing click here.