While Maura's heart is in the right place in trying to get Jane to eat better, the chemicals she lists from the cupcake packaging will not harm the fetus in such quantities. (Anything, of course, can harm a person if ingested in large enough quantities, including plain water.) The fact that such chemicals are also used for industrial practices does not mean that they are not edible. Calcium carbonate, for instance, is commonly used in antacids; pregnancy can lead to heartburn, which would be treated with an antacid. It is unlike Maura to make such generalizations.