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13 plants that could kill you

By: Bryan Nelson on April 12, 2010, 12:16 p.m.
Castor beans

Photo: Wiki Commons/public domain

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Castor beans

If you have consumed castor oil before, you might be surprised to learn that castor beans contain one of the most poisonous substances in the world, ricin. Just one castor bean has enough ricin to kill an adult within a few minutes. Despite this grim quality, castor bean plants are frequently grown for decorative purposes.