The Great American Rain Barrel is a re-purposed shipping drum for food products and is Food Grade polyethylene, UV protected and BPA free.  It starts as a  place to store and ship food products.  To  retrofit the barrel for water collection, holes are drilled into the lid and sides of the barrel so it is no longer sealed. It is designed to collect water off of your roof, which will have bacteria and contaminants.  Rain barrels are not for storing drinking water.