Insects, toxic venoms from

While there is often focus on the poisonous effects of synthetic chemicals, the most poisonous chemicals are bacterial toxins, marine toxins, fungal toxins, mycotoxins, venoms (from snakes, insects, arachnids, and other animals), and some plant toxins. Table 4.1.1.2 shows the LD50 values for toxicants including poisons and nonpoisons. This can help you judge the relative acute toxicity of a chemical, but it does not indicate chronic or long-term toxicity. Whether a substance is fatal, toxic, or harmful also depends on the dose, of course. There is also no relationship between toxicity and whether a compound is simple or complex. The mechanism of toxicity varies greatly, and structure-activity relationships are not simple (see Chemical Connection 4.1.1.1 Structure-Activity Relationships). 

The toxicities of insect venoms are low to most people. Despite this, relatively large numbers of fatalities occur each year from insect stings because of allergic reactions in sensitized individuals. These reactions can lead to potentially fatal anaphylactic shock, which affects the nervous system, cardiovascular function, and respiratory function. The agents in bee venom that are responsible for severe allergic reactions are mellitin and two enzymes of high molecular mass — hyaluronidase and phospholipase A-2. 

In antiquity, natural toxins were exploited to make poison weapons to wage the earliest forms of biological and chemical warfare. A wide range of substances, from toxic plants and venomous insects and reptiles to infectious agents and noxious chemicals, were weaponized in ancient Europe, the Mediterranean, North Africa, the Middle East, Central Asia, India, China, and in the Americas. Evidence for the concept and practice of toxic warfare can be traced back thousands of years. Eor example, cuneiform tablets from about 1200 bc record that the Hittites of Asia Minor deliberately drove plague victims into enemy territory. 

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