Silica gel itself is harmless to human body, but harmless chemicals must be added during production.

Silica gel characteristics: temperature: -50~280 degrees.

Resistant to all external media.

Production inspection level: environmental SGS, food FDA, medical grade.

So silica gel is harmless to human body.

But the cause of hardening is estimated to be: the time is too long, exceeding the time limit.

It is recommended to replace.