What is the blue material from the battery?

There's an old battery here. There's something like blue material running out here. What is this?

Is it dangerous?

893 2018-04-30 Gentleman

If the battery is old and rust occurs, that's how blue corrosion occurs

Gentleman 7 years ago 0

There's copper in the battery, and when it rusts, it becomes blue
It's because it came out of the battery
Copper rust is toxic, so it's best not to touch it
If it was enough to make copper flow out, cadmium would have flowed out, but cadmium is highly toxic
It's good to throw it away carefully

Gentleman 7 years ago 0

A. 3

Thank you for the detailed explanation!

Gentleman 7 years ago 0

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