Four men were arrested Tuesday by federal authorities and charged with plotting to make ricin and buy explosives to attack government officials.

The men – who are in their 60s and 70s – are part of a Georgia militia group who tried to get an unregistered explosive device and find the formula that makes ricin, according to a federal complaint.

Of all the biotoxins that terrorists use, ricin is one of the most concerning – even though you probably need a large quantity for significant population impact.

Ricin is naturally-made from castor beans, and even a small amount well-distributed to a single person could be deadly.

On the positive side, it’s not contagious and cannot be spread from person to person. 

However it can have a deadly effect once you get into direct contact with it.

The way this toxin works is that once it’s inside your body, it destroys cells by not allowing them to multiply and you have cellular death.

There are three ways you can get exposed to ricin. The first is direct skin contact, which is probably the least harmful effect and you would get a rash or burning sensation.

However the two most deadly ways of ricin poisoning is through inhalation or through your digestive tract.

In case of inhalation, usually within eight hours of exposure you will tend to have difficulty in breathing. This is due to the destruction of lung tissue that develops, and this will lead to fluid buildup in your lungs and ultimately will lead to death.

The only way to treat this inhalation poisoning is to seek medical help immediately, in which doctors will try to maintain air flow into your lungs, as well as keeping your body fluids in balance.

If you swallow even small amounts of ricin, you will develop vomiting and diarrhea, which ultimately could lead to significant gastrointestinal bleeding, and this bleeding affects your liver and kidneys, and you could die.

As you can see the only treatment of ricin is supportive, there is no antidote for it.

There are some ways you can protect yourself if you think you have been exposed to ricin.
1. Flee from contaminated immediately
2. Remove all your clothing and wash down with soap and water
3. Remove contact lenses or eyeglasses
4. Immediately seek medical attention
5. And if you think you have ingested ricin, do not induce vomiting or try to ingest fluids to clear out the poison

Prosecutors say one of the four men spoke of making 10 pounds of ricin and spreading it around Atlanta and other cities across the country. Another man from the group is accused of showing him how to get the ingredients needed to make ricin and showing him the formula.

The group will make a court appearance Wednesday.

Dr. Manny Alvarez serves as FOX News Channel's (FNC) Senior Managing Editor for Health News. Prior to this position, Alvarez was a FNC medical contributor.