Learn how ricin poisoning occurs, the signs and symptoms of poisoning, and what to do if you’re exposed.

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Ricin is a toxic protein naturally found in the seeds of the castor bean plant. Produced as a byproduct of castor oil production, ricin is one of the most potent toxins. It’s a potential agent for biological warfare.

Because of this, ricin has been categorized as a category B agent — the second highest priority level — for bioterrorism. It’s strictly regulated by the Organisation for the Prohibition of Chemical Weapons.

Ricin may be found in food, as a powder, in pellets, in a mist, or dissolved in water.

Ricin poisoning can occur if you become exposed to a large amount of ricin via three routes: oral ingestion, injection into the body, or inhalation.

From food

The seeds of the castor bean plant contain ricin. If you eat the raw seeds, you risk exposure to dangerous levels of ricin and the development of life threatening ricin poisoning.

Symptoms of ricin poisoning may develop within 10 hours of ingestion.

Nonscientific sources suggest that, in children, consuming a single castor bean seed may be lethal. In adults, consuming three or more seeds may be lethal.

According to the Centers for Disease Control and Prevention (CDC), ricin poisoning from food and cooking is highly unlikely.

Temperatures above 176℉ (80℃) inactivate the ricin toxin. This means that cooking foods thoroughly will get rid of any toxins that may have been present in the food.

From inhalation

Inhalation of ricin is believed to only occur through a deliberate act of biological warfare.

The ricin may be concentrated and developed into a mist or powder and released into the air. If you’re near it, you risk exposure to lethal doses.

Symptoms of ricin poisoning from inhalation may develop within 4 to 8 hours of exposure.

Other exposures

Ricin poisoning isn’t contagious. It can’t be transmitted between people through casual contact.

However, if you come into physical contact with someone who has ricin on their body or clothing, then touch your nose or mouth, you do risk inhaling or ingesting ricin.

Likewise, ricin doesn’t enter the body through intact skin. Poisoning may occur if ricin enters into broken skin, the mucous membranes in the eyes, nose, and mouth, or through injection.

The symptoms of ricin poisoning depend on the route of exposure and the dose.

For instance, inhaling ricin leads to respiratory-related symptoms. Oral ingestion causes abdominal distress. Skin exposure causes inflammation of, and damage to, the skin.

Common symptoms of ricin poisoning include:

  • cough
  • skin inflammation and discomfort
  • nausea and vomiting
  • fever
  • tightness in the chest
  • difficulty breathing
  • diarrhea that may become bloody
  • blood in the urine
  • seizure
  • organ failure

Regardless of the route, death from ricin poisoning can occur within 36 to 72 hours if left untreated.

This is because ricin causes cell death by stopping the production of proteins within the cells. Without these proteins, the cells eventually die, and organ function is compromised.

A prompt response is required to reduce the risk of developing ricin poisoning after exposure.

If you have been exposed to ricin, the CDC outlines things you can do before seeking medical attention:

  • If ricin is released into the air, move away and get fresh air immediately.
  • If ricin gets on your clothing, remove your clothes and wash your skin with large amounts of soap and water.
  • If ricin has entered your eyes, remove your glasses or contacts, and rinse your eyes with plain water for 10 to 15 minutes.

After taking these preliminary measures, immediately seek medical attention for further evaluation and treatment.

To learn more about ricin poisoning and measures you can take to protect yourself, contact poison control at 800-222-1222, or the CDC’s public response hotline at 800-CDC-INFO (888-232-6348).

Despite the harmful effects of ricin poisoning, ricin may hold promising benefits for future use in cancer treatments.

For instance, cell-based research has demonstrated that ricin may be effective at targeting and stopping the growth of cancerous tumors by inducing cell death of the cancer cells.

Likewise, the potential therapeutic benefits of the specific ricin A-chain were observed in research focused on the use of antibodies in the treatment of various cancers.

The toxic ricin A-chain may be coupled to monoclonal antibodies that are used in cancer research to slow or stop the growth of cancer cells completely.

Therefore, ricin may have potential as an anticancer compound, but only if research in humans can demonstrate it effectively treats various types of cancers.

As documented in the 1980s, the castor bean plant (Ricinus communis) has been part of traditional medicine systems in over 50 countries.

Although there is little scientific research, the castor bean plant is believed to possess antioxidant, anti-inflammatory, and anti-microbial properties that potentially benefit some health conditions.

Also called Ernada, all parts of the castor bean plant — the leaves, roots, and oil from its seeds — have been traditionally used for:

However, long-term human research is needed to determine whether the castor bean plant is effective in treating these conditions, as well as the safe dosages at which these benefits may be attained.

The castor bean plant is used in many traditional medicine systems, but its seeds contain the potent toxin ricin.

Ricin is typically produced as a byproduct of castor oil production. Ricin can cause life threatening poisoning if large amounts are ingested, inhaled, or injected into the body.

Despite the fatal potential of ricin poisoning, ricin may have potential as a future anticancer treatment due to its ability to cause cell death of cancerous cells and tumors.