Toxins, threats

Nonetheless, we must consider subpopulations of troops and areas within which they operate when we estimate vulnerability to a given toxin threat. Because of differences in operational environments, situations could well occur in which different populations of troops require protection from different toxins. To protect them effectively, military decision makers and leaders must understand the nature of the threat and the physical and medical defense solutions. 

We are making good progress on developing recombinant vaccines for certain high-threat toxins. In the future, protection of our soldiers from toxin threats will be limited only by our willingness to use the vaccines. Similar technology allows us to produce human antibodies, which will eventually... 

In summary, it can be reported that toxic cyanobacteria can produce neurotoxic, hepatotoxic, and dermatotoxic compounds that are a direct threat to animal and human water supplies. This threat increases as water bodies become more eutrophic, thus supporting higher production of toxic and nontoxic cyanobacteria. Presence of these potent natural product toxins poses an increasing threat to the maintenance of quality water supplies for agriculture, municipal, and recreational use. 

The interplay between the chemical and biological properties of the threat agent, on the one hand, and the specific attack scenario, on the other, can influence the lethality of the attack. Table 2-2 shows the relative respiratory toxicities (expressed as the lethal concentration of toxin at which 50 percent of test animals are killed, or LCT50, in milligrams per minute per cubic meter) of a variety of toxic gases compared with chlorine gas, which was used as a chemical weapon in World War I. According to Table 2-2, the nerve agent sarin (GB) has a respiratory toxicity approximately 100 times that of chlorine, while sulfur mustard (HD) is about 7 times more toxic. However, the lethality of an attack... 

Category B agents There are eleven Category B agents as follows brucellosis, epsilon toxin (clostridium perfringens), glanders, melioidosis, psittacosis, Q fever, ricin toxin, staphylococcus enterotoxin B, typhus fever, viral encephalitis, and water safety threats. 

The combination of the wasps own toxins and those provided by the virus affect tobacco hornworms in other ways as well. One of these is to modify their behavior to the wasps benefit. Parasitized caterpillars continue to feed and behave normally until about eight hours before the larvae emerge. At that time, the caterpillars cease to eat and crawl about. They show no other deficiency and their reflexes appear normal. The details of this modification are uncertain, but it appears to favor the wasp larvae. A normal, unparasitized caterpillar readily eats wasp pupae offered to it. This implies that an active caterpillar would be a threat to larvae emerg-... 

The saxitoxins from dinoflagellates of the genus Protogonyaulax may accumulate in shellfish and, being potent neurotoxins, pose a serious threat to public health. Six of the saxitoxins are sulfamates which have relatively low toxicity, but are easily hydrolyzed to the respective carbamates with corresponding increases in potency. This paper presents some of the chemistry and public health implications of these toxins. 

The red tide alga Prymnesium parvum poses a serious threat to fish farming. Prymnesin-2 (184) (CggHnsC NC ), the major toxin of the phytoflagellate, shows potent hemolytic and ichthyotoxic properties. The minimum concentration to cause hemolysis of a 1% mouse blood cell suspension and to kill fresh water fish, Tanichthys albonubes, is 3 nM [145]. 

Cyanobacteria blooms can pose an extremely serious threat to human health (970-972), and some of the causative toxins contain halogen. The fresh water toxic cyanobacterium Oscillatoria agardhii produces oscillaginin A (916), which features the novel 3-amino-10-chloro-2-hydroxydecanoic acid, and is the source of the micro-cystins, which are heptatoxins (973). The prolific cyanobacterium Lyngbya majuscula from Curacao has furnished the novel barbamide (917) (974) and dechlorobarbamide (918) (975). Extensive biosynthetic studies show that the amino acids leucine, cysteine, and phenylalanine are involved in barbamide production (976-982). The chlorination of leucine is of great interest and may involve a radical mechanism (976, 980-983). 

Among biotic agents fungi that produce toxins are an important and widespread threat that can contaminate cereals. 

In one study, 44 species of fungus were isolated from 30 samples of khat leaves gathered in Yemen. Researchers considered the toxins found in some of these species a threat to public health. 

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