A new study has found that some water filters not only fail to remove potentially harmful permanent chemicals from drinking water, but may actually increase the amount of these toxins if they are not properly maintained,media reported. The study was conducted by researchers from Duke University and North Carolina State University. The team found that not all household water purifiers remove toxic perfluoroalkyl substances (PFAS).
The toxin, known as PFAS, usually comes from pesticides and foams used by firefighters. Unlike some toxins, these substances are called “permanent chemicals” because they remain in the environment, especially in drinking water. Exposure to these chemicals can cause negative health effects such as thyroid disease and cancer.
Some water filters can remove these chemicals, but according to new research, they have different effects. In general, two-stage and concealed reverse osmosis filters can almost remove the PFAS toxin contained in water.
However, more commonly used activated carbon filters, such as tap filters, have greater variability in whether they can be removed from these substances. At the same time, in some cases, whole-house water filtration systems actually increased the amount of PFAS water;
Two-stage filters and reverse osmosis filters remove 94% or more of PFAS, while activated carbon filters remove an average of 73% of all PFAS toxins, while some have no obvious effect. Sadly, the researchers point out, the most efficient choice costs are much more expensive, meaning that lower-income people are more vulnerable to toxins than wealthier families who can afford these systems.