In a test done by us, the walls of a foam plastic cup containing liquid from a Lovaza capsule began to dissolve within a minute; the bottom of the cup dissolved after 10 minutes. Other liquid capsule products such as vitamin E did not appear to affect the cup.
It is not known whether it is the omega-3-acid or some other component of the liquid that is causing this reaction. The effect upon other types of plastic (e.g., special plastic syringes used for oral liquids) and potential toxicity from dissolved plasticizers is also unknown but clearly needs to be investigated by companies that provide omega-3-acid products so information can be added to labeling.
Until more is known, we’ve mentioned to the Lovaza manufacturer GlaxoSmithKline that, at a minimum, the label needs to warn about contact with plastics. If you need to mix the product in fluids before swallowing, we recommend that you use a small glass.
Incidentally, “Styrofoam” is a Dow Chemical Company trademark for a different plastic than foam used in cups.