3. Blood Disorders. Blood disorders such as hemophilia and leukemia can cause unexplained bruising, often because your blood fails to clot properly. If you have severe and frequent unexplained bruising, it's a good idea to see a physician to rule out such disorders, especially if it seemed to come on suddenly.
Puffer fish contain the potent neurotoxin tetrodotoxin. TTX is thought to be synthesized by a bacterial or dinoflagellate species associated with the puffer fish. The toxin is concentrated in the liver, gonads, and skin. The level of toxicity is seasonal, and, in Japan, fugu is served only from October through March.
Interestingly while tetrodotoxin is found in several different branches of the animal kingdom, the tetrodotoxin found in each of these creatures is identical - unlike the venoms produced by snakes and scorpions which are made up of different kinds of toxins particular to that species.