Using a skin-blurring makeup primer before you apply foundation is a given for most beauty obsessives—but one of the go-to ingredients, silicone, remains debatable. "Silicones smooth and plump the skin while locking in moisture due to their occlusive nature," says Melodie Reynolds, founder of Elate Beauty. However, concerns have risen amongst clean beauty fans and environmentalists alike that silicones—a rubber-plastic hybrid— may not "simply dissolve as they go down the drain," as Reynolds puts it. While research is still ongoing, opting for a silicone-free makeup primer can help assuage any worries. Ahead, shop our editor-approved formulas that smooth skin and lock in makeup, all without silicone.