[refurb]

Random story - I met the chemist who worked at Searle and whose job it was to come up with a way to purify aspartame on an industrial scale.

Normally purifying things like pharmaceuticals can be challenging, but as long as impurities are under 0.5%, generally they are acceptable (some have lower limits).

But with aspartame it had to be much cleaner since small impurities would ruin the taste. So it had nothing to do with safety but more quality of the final product.

He banged his head against the wall until they came up with a process that consistently have high quality product as measured by taste.