Apparently the microwavable pad housed a chemical substance (manufactured by ADEKA) not quite stable enough to handle the heat, sparking a lengthy list of of cases where the liquid erupted from its container and provided an uncomfortable surprise to the poor soul embracing the creature's volcanic warmth.

ENGADGET: Exploding Hello Kitty toys recalled

From a chemical perspective, high-weight phthalates are tightly bound, more stable and more resilient than low phthalates.

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