## 6 BoNTs Association with Bioterrorism CBRN (Chemical, Biological, Radiological, Nuclear) Events  
There are poisons (biotoxins) produced by living organisms, some of which have chemical-physical characteristics that make them suitable for possible uses as offensive weapons (bioterrorism). They are produced by bacteria, fungi, algae, and other plant and animal organisms, some of which have already been known by the ancients both as poisons for hunting and for their therapeutic properties [70; 71]. Some biotoxins have even greater toxicity than that of some synthetic ones (such as nerve gases), but not all have stability characteristics, particularly at temperature and sunlight, so they do not always have the chemical-physical characteristics to be used without risk for whoever intends to use them. A first attempt to overcome these considerable drawbacks was to microencapsulate them (stable to temperature and sunlight, obtaining higher levels of danger). In 1972, the international convention on biological weapons and toxins, signed by 140 countries, decreed a ban on their use for military purposes [72; 73; 74]. However, it must be emphasized that currently, thanks to genetic engineering techniques, it is possible to produce toxins in large quantities, as well as modify their original structure, both to enhance their aggressive characteristics and improve stability, and to try to obtain a programmed release through a progressive degradation of the envelopes with which they are covered and conveyed [74].  
BoNT-A and BoNT-B are among the best known biotoxins that have a high risk of unconventional events CBRN (chemical, biological, radiological, and nuclear) and are bioterrorism agents due to their high lethal toxicity (they are the most toxic known toxins). Their toxicity is about 100,000 times more toxic than organophosphorus nerve gas (Sarin). The mean lethal dose of BoNT-A in humans is 0.09-0.15 \(\upmu\)g for 70 kg when administered intravenously or intramuscularly, 0.7-0.9 \(\upmu\)g when inhaled, and 70 \(\upmu\)g when administered orally. Before the Gulf War, Iraq produced 20,000 L of BoNTs, with the production of warheads bombs containing toxins. Several terrorist groups have experimented with BoNTs, including members of the religious sect of Aum Shinrikyo, known for the 1995 Sarin gas attack on the Tokyo subway [75; 76].  
The main ways of causing this disease are by inhaling toxins or by administering it through food. In case of botulism due to inhalation, since it cannot occur naturally, there is an association with an accident or a terrorist attack with air pollution with botulinum toxins in aerosol form. One gram of pure crystalline BoNT theoretically with smooth distribution after inhalation could kill more than one million people. For this reason, it belongs to the A category of the CDC (USA) and is also a banned substance of the Biological Weapons Convention [70; 72; 75].  
The factors that would make the use of the BoNTs by terrorists possible are the following: (a) extremely high toxicity, (b) resistance to changing environmental conditions, (c) ease and low cost of production as the bacteria that produce them are widely available, but also the fact that there are commercially available formulations containing botulinum toxins for medical and cosmetic purposes (Botox(tm)) from which they can be isolated, (d) the possibility of adding them to aerosols for spraying as they can be stored in powder form, and (e) the possibility of adding them to foods and beverages that will not be heated before consumption [75; 76; 77].