For a food to be labeled as natural, it must be free from food colors, artificial flavors and any other synthetic substances. (birthingnaturally.net)
Even more concerning is that potential toxic effects of synthetic substances interacting in cosmetics, both within the same product and when several cosmetic products are used repeatedly every day, are barely understood. (odylique.com)
It's far cheaper to extract oil from, say, citrus fruits than from flowers; companies that charge the same for every kind may very well be including synthetic substances. (health.com)