16 CFR § 1507.2 - Prohibited chemicals.
Fireworks devices shall not contain any of the following chemicals:
(a) Arsenic sulfide, arsenates, or arsenites.
(c) Chlorates, except:
(1) In colored smoke mixtures in which an equal or greater amount of sodium bicarbonate is included.
(2) In caps and party poppers.
(3) In those small items (such as ground spinners) wherein the total powder content does not exceed 4 grams of which not greater than 15 percent (or 600 milligrams) is potassium, sodium, or barium chlorate.
(d) Gallates or gallic acid.
(e) Magnesium (magnesium/aluminum alloys, called magnalium, are permitted).
(f) Mercury salts.
(g) Phosphorus (red or white). Except that red phosphorus is permissible in caps and party poppers.
(h) Picrates or picric acid.
(j) Titanium, except in particle size greater than 100-mesh.