Food - Drink
Why Filtering Water Doesn't Necessarily Make It Safe To Drink
By ELIAS NASH
Due to widespread pollution, water quality is deteriorating all over the world, leading to increased purchases and use of portable water filters. However, putting your water through a filter is not always enough to make it safe to drink, especially when it comes to viruses like E.coli, salmonella, giardia, and norovirus.
The National Park Service explains the very small holes in water filters can sift out dirt and bacteria, but viruses are small enough to pass through. The most effective type of filter is a reverse osmosis system, which uses multiple screens, an activated carbon filter, and a mesh membrane to remove microscopic contaminants.
Another water safety practice is UV purification, which uses ultraviolet light to kill microorganisms. However, if you live in an area with low-quality, potentially contaminated water, the most surefire way to kill bacteria and viruses is to boil your water for one minute, or for three if you live at a higher elevation.