This warning label is required by California Law for all products and produce made within the state. California has the strictest heavy metal testing in the world. Even some of the produce (i.e., spinach) at local grocery stores must bear the Prop 65 warning. This warning lets consumers know a product comes from the ground and that soil may contain traces of chemicals or heavy metals. Suja Organic Greens goes through strict 3rd party testing, is certified USDA Organic & Non-GMO Project Verified to ensure we are delivering the highest quality & safest products to our consumers.