Toxicity
Abrin works by penetrating the cells of the body and inhibiting cell protein synthesis. By attaching to a carbohydrate chain on the cell surface, the abrin molecule anchors itself to the cell, is subsequently engulfed and enters the inner parts of the cell where it reacts with a ribosomal subunit and interferes with the normal protein synthesis process of the cell. Without these proteins, cells cannot survive. This is harmful to the human body and will be fatal. The severity of the effects of Abrin poisoning vary on the means of exposure to the substance (whether inhaled, ingested, or injected).
The estimated LD50 for humans is estimated to be between 100 ng and 1 µg, and it is considered to be extremely toxic.
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