Phosphate buffer is used to keep the pH steady. You could drink it and be just fine.

Luciferin is a substrate acted on by an enzyme to emit light. It was named in a tongue in cheek manner I'm sure, but one could always put on a tinfoil hat and look more into that.

Rushing a vaccine for a virus that isn't any more deadly than the seasonal Influenza, with widespread government support and little testing, now that is far more worrisome than these "ingredients".