The skins of potatoes alone are not poisonous. However, if the potatoes have begun to sprout, the skin around the sprouting, and the potatoe below that, may contain poisonous materiasl.
The chemical in question is solanine, a toxin that forms in the sprouts and green parts of potatoes. You can avoid it by cutting away sprouts ("eyes") from potatoes and peeling them below any green layer. And don't eat any potatoes that taste bitter; the flavor might indicate the presence of solanine.
Potatoes contain glycoalkaloids, toxic compounds, of which the most prevalent are solanine and chaconine.
Breeders try to keep solanine levels below 200 mg/kg (200 ppmw). However, when these commercial varieties turn green, even they can approach concentrations of solanine of 1000 mg/kg (1000 ppmw). In normal potatoes, analysis has shown solanine levels may be as little as 3.5% of the breeders' maximum, with 7-187 mg/kg being found.
The poison is found throughout the plant, but especially in green potatoes and new sprouts. Never eat potatoes that are spoiled or green below the skin. Always throw away the sprouts.
Potatoes that are not green and have had any sprouts removed are safe to eat.
* Dilated pupils
* Loss of sensation
* Lower than normal body temperature (hypothermia)
* Slow pulse
* Slowed breathing
* Stomach or abdominal pain
* Vision changes
Hope this answers your question..