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Q & A: gunk in electric toothbrush

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Most recent answer: 04/09/2017
Q:
My son is 4 and has one of those electronic toothbrushes. He went to brush his teeth tonight and it started making brown liquid. I dissembled the toothbrush and took the batteries out and they were covered in rust... I hope it wasn't battery acid. My question is.. Should I be concerned about him investing that for what could have been a long time period? I really have no idea how long it was like that.
- Gayle (age 29)
Lenexa, KS, USA
A:

There are several things we don't know that would be needed to answer that question.

Some electric toothbrushes have the batteries well sealed away from the brush itself. In a toothbrush like that, brown rust on the outside would come not from the batteries but from the magnets rusting. That happens on mine. The magnets are very strong, so I guess they contain neodymium. It's a bit toxic, but not acutely so.

It sounds like yours may not have the batteries so well sealed away. If the outside rust does come from the battery, I'd contact the manufacturer to find out what type of battery they use. if, as is most likely, the battery is of the NiMH type, it's not very toxic. If it's a NiCad, that's more of a problem, since cadmium is quite toxic.

My guess is that there's nothing to worry about, but you should check.

Mike W.


(published on 04/09/2017)

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