lye is the common name for sodium hydroxide, although it's not technically pure. that anodizing removing powder is nothing more than pure sodium hydroxide - which is why you should wear gloves and goggles.

sodium hydroxide has a pH of 14 (lye has a pH of 13), so if you injest it, you'd better hope that they can restore your blood's pH (7.4) before your organs are slush. it's extremely caustic, the base equivalent of hydrochloric acid (pH 0).

i sort of wonder if he could have spared himself the new wheelset, if he was able to submerge the wheel to right below the hub flange on top and then on bottom, and then submerged the small "left" and "right" portions of each wheel at the same time.