Cinnamon-flavored applesauce pouches sold in grocery and dollar stores last year poisoned hundreds of American children with extremely high doses of lead, leaving anxious parents to watch for signs of brain damage, developmental delays and seizures.The Food and Drug Administration, citing Ecuadorean investigators, said a spice grinder was likely responsible for the contamination and said the quick recall of three million applesauce pouches protected the food supply.But hundreds of pages of documents obtained by The New York Times and the nonprofit health newsroom The Examination, along with interviews with government and company officials in multiple countries, show that in the weeks and months before the recall, the tainted applesauce sailed through a series of checkpoints in a food-safety system meant to protect American consumers.The documents and interviews offer the clearest accounting to date of the most widespread toxic exposure in food marketed to young children in decades. Children in 44 states ate the tainted applesauce, some of which contained lead at extraordinarily high levels.Time and again, the tainted cinnamon went untested and undiscovered, the result of an overstretched F.D.A. and a food-safety law that gives companies, at home and abroad, wide latitude on what toxins to look for and whether to test.“It’s amazing in a bad sense what a catastrophic failure this was,” said Neal Fortin, director of the Institute for Food Laws and Regulations at Michigan State University. “Largely, the food supply regulatory system is based on an honor system.”We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.