nightshade
Lovin' The Homestead
agreed... but detergent and teat dip/ iodine should not cause any concerns. I would just wash them well before using them for water collection. This is for watering plants not drinking or watering livestock with. Your biggest concern when not buying food grade barrels is did it hold a petroleum product in it? If so it is no good for rainwater collection. The petro leaches into the plastic and will leach back into the water over time.