All parts of the plant are highly toxic.[22] However, the highest concentrations of toxins tend to be in the rhizome.[22] Toxicity varies widely depending on the method of preparation (extract, water extract, etc.), and the method of application.[22] Just 1.8 grams (0.063 oz) per 1 kilogram (2.2 lb) can cause death due to cardiac arrhythmia.[23] Death has even occurred at a dosage as low as 0.6 grams (0.021 oz).[24]