NMCL (the Berkey manufacturer) has released test results for the removal of perfluorinated chemicals from drinking water. Perfluorinated chemicals are chemicals such as PFOAs, PFOCs and C8, they are used in the manufacture of teflon, stain resistant fabric and fire retardants. The Black Berkey water filters were found to remove perfluorinated chemicals to a level of more than 99.9%.
Perfluorinated chemicals are carcinogenic and accumulate in the environment. These chemicals recently (July 2017) came into the news due to an alarm raised by the Dutch authorities over the dumping of waste water containing GenX, a similar chemical compound which is closely related to perfluorinated chemicals. For more information regarding the effectiveness of the Black Berkey water filters in the removal of GenX please see our blog post from August 2017.
For the complete perfluorinated chemical reduction lab report please see: Perfluorinated Chemical Reduction Lab Test Results.