[Sticks]

It was not lead in hats that caused the problems with hat makers, it was actually mercury, which was the problem



Link

Although the name 'Mad Hatter' was undoubtedly inspired by the phrase "as mad as a hatter," there is some uncertainty as to the origins of this phrase. As mercury was used in the process of curing felt used in some hats, it was impossible for hatters to avoid inhaling the mercury fumes given off during the hat making process. Hatters and mill workers often suffered mercury poisoning as residual mercury vapor caused neurological damage including confused speech and distorted vision. It was not unusual then for hatters to appear disturbed or mentally confused; many died early as a result of mercury poisoning. However, the Mad Hatter does not exhibit the symptoms of mercury poisoning. Principal symptoms of mercury poisoning are "excessive timidity, diffidence, increasing shyness, loss of self-confidence, anxiety, and a desire to remain unobserved and unobtrusive."

I expected this of Bea, but not Halfwit