Water filtered by Berkey systems can be used for bottle preparation or as drinking water for infants. Pollutants have been removed from the water and minerals have been retained. Take extra precautions if the filtered water comes from untreated water such as rainwater or a natural borehole to ensure that the system is fully operational and that the filtered water does not contain residual pollutants due to extremely heavy pollution or an exceptional pollutant that is not completely removed from the filtered water.
More information on natural spring water filtration here.