In Bshad rgyud, it is pointed out that, "For herbs from root, stem, cortex, branch, leaf, flower and fruit, only a few are toxic;juice, fat, marrow are not toxic. There is, however, likely to be toxicity in the skin filth, inner membrane and tenacious skin. Detoxified herbs are easily digested and mild." The toxicity of root and stem is located in the cortex and medulla, which should be discarded; the toxicity in a branch is located in the joints which should be removed except that in Radix Rubia; toxicity of leaves is located in the stalk, that of flowers, in the perianth. For fruits, sometimes its nuts are also used; skin toxicity refers to the black filth formed after being exposed to sunshine and rain; tenacious skin toxicity refers to the external layer of the stem; juice, marrow and fats refer to resins. Someone has claimed that these three are non-toxic. The juice from herbs such as Radix Euphorbia is milky white and toxic, so should be discarded.Similarly, the oil and marrow of Fructus Croton is also toxic, but if they are removed the effect will be preserved.