Lead residue
It strikes me as a VERY poor idea to wash brass in a washing machine that is used for your clothing. Brass comes with a certain amount of lead residue on and especially inside the cases. This is not from the bullet, the lead of which may never touch the case, but from the lead styphnate used in the making of modern primers.
Mercury fulminate was the old compound used for primers, but that left metallic mercury inside the cases, which attacked the brass vigorously, not to mention that metallic mercury is not good for human beings. These were the old so-called corrosive primers. Then they changed to lead styphnate, the residue of which does NOT attack the brass, therefore the brass lasts longer. But if you wash it out in a washing machine, you get a washing machine contaminated with lead.
Were you to then wash your underwear in that machine, you'd be getting lead in your pants, which would not please your boss
but far worse, some could be absorbed into your body. Lead in the body does nasty things to the central nervous system.
Frankly, I don't know exactly how much of a danger there is here. But I do NOT intend to play the guinea pig and find out.
One of the contributory factors to the fall of the Roman Empire was lead in the Roman drinking water, leached out of the lead water-supply pipes. As time passed, the Romans made worse and worse decisions about the running and defense of the Empire. The lead built up over the years in their brains.
Anyhow, I'm solidly with Bushmaster's wife on this one. Fired brass in the washing machine. It's a Bad Thing.