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Top 10 Most Poisonous Plants


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The Rosary Pea

The rosary pea, or Abrus precatorius, has very pretty seeds. Two-thirds of the seed is red, and the top third is black. These decorative seeds are often used to make jewelry, and that jewelry is imported to other countries. In fact, these seeds are especially popular for rosary prayer beads.

But rosary pea seeds contain the poison abrin. The seeds are only dangerous when the coating is broken -- swallowed whole, the rosary pea doesn't present any danger. But if the seed is scratched or damaged, it's deadly. The rosary pea poses greater danger to the jewelry maker than to the wearer. There are many reported cases of death when jewelry makers prick a finger while handling the rosary pea.

Rosary pea plant is an aggressive grower and can take over an area if not kept in check. One rosary pea vine can grow and climb more than 20 feet (6 meters) in a single season. The plant, which is native to Indonesia, has spread across the world, in tropic and sub-tropic climates. It's even located in several states in the United States, including Alabama, Arkansas, Florida, Georgia and Hawaii. The plant has long leaves with off-shooting leaflets and red flowers.

Abrin, the poison found in the rosary pea seed, is more deadly than ricin. Less than 3 micrograms of abrin in the body is enough to kill, which is less than the amount of poison in one pea. In the human body, abrin bonds to cell membranes and prevents protein synthesis, one of the most important duties of the cell. Symptoms of rosary pea inhalation poisoning are: difficult breathing, fever, nausea and fluid in the lungs. If ingested -- and the seed coating is broken -- rosary pea seeds cause severe nausea and vomiting, which eventually leads to dehydration, and ends with the kidneys, liver and spleen shutting down. Death usually follows within three to four days.


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