Toxin
A toxin is a poisonous substance that can be produced by various sources, including plants, animals, fungi, and bacteria. While many people associate toxins primarily with natural origins, they can also include heavy metals and even excessive sun exposure. The Centers for Disease Control (CDC) has identified particularly lethal toxins from different categories, such as botulinum and ricin, which pose significant threats to human health. Historically, the study of toxins has roots in ancient medicine, with early texts detailing the effects of herbal substances and the relationship between dosage and toxicity. Exposure to toxins can be acute, resulting in immediate symptoms, or chronic, leading to long-term health issues that may be subtle initially. The impact of toxins extends beyond humans, affecting ecosystems and various species differently—what is harmful to one organism might be harmless to another. For example, chocolate is safe for humans but toxic to dogs. Additionally, the accumulation of toxins in the environment can signal broader ecological issues, like the decline of bee populations, which are crucial for pollination. Overall, understanding toxins is essential for both health and environmental sustainability.
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Toxin
Toxin is a term used to describe a poisonous substance. Generally toxins are produced by plants or animals; but that is a narrow definition. Heavy metals and even over-exposure to the sun can be toxic. Some agents are dose-related; while others are dangerous to living organisms even in miniscule quantities. The Centers for Disease Control (CDC) identifies a group of the most lethal chemicals produced by plant toxin from algae, bacteria, fungi, and plants. Toxic bacteria include Anthrax, Botulinum, Pertussis, Staphylococcal enterotoxin B (SEB). Fungi and algae (mycotoxins) include Aflatoxins, Saxitoxin, neosaxitoxin, amanitin, vomitoxin (deoxynivalenol), diacetoxyscirpenol, as well as T-2 and HT-2 toxins. All mycotoxins are considered bioterrorism threats. Plant toxins include Abrin and Ricin. The CDC considers only Botulinum, Epsilon toxin, Ricin, and Staphylococcal enterotoxin B, to be a high-threat with potential mass casualties.
Background
Toxicology is not new or modern. The man called the Chinese father of medicine, the Red Emperor Shen Nung, wrote the first known treatise On Herbal Medical Experiment Poison. He also is credited with the first Chinese pharmacology text, said to be by divine revelation. There are many myths about him, just as there are spellings of his name. However, the cataloging of 365 plants and their effects was likely the first study of toxicology. It is noteworthy that he is said to have died from being poisoned.
Intentional use of toxins as weapons had an early start. Homer describes arrows being covered in venom. It is also where readers see the first use of the word "toxin": coming from the Greek word "toxikon," which means poison. Humankind has had a fascination with poisons for most of written history. Interestingly, toxic materials have been used to both cure and kill since ancient times. Many modern life-saving pharmaceuticals are derived from, or the result of studying, sometimes lethal sources.
Moses Maimonides, a Jewish physician, may have made the initial leap into curing the effects of toxins. He wrote the first known Treatise on Poisons and Their Antidotes in 1135. However, it was not until about the early 1500s that Paracelsus identified the relationship between dose and effect. He also demonstrated specific chemicals within plants and animals that were responsible for the production of toxins. He is noted for a principle used and understood even more in the twenty-first century than ever: "Everything is poison, there is poison in everything." That is a significant point with wide applications. Even something as innocuous as water, which is a vital substance for most plants and animals, can kill if too much is ingested.
Studying toxins is not simply an academic pursuit. Science has learned that what causes damage and how, is the first step in finding the cure.
Impact
Exposure to toxins is measured in two categories: acute (sudden) and chronic (long lasting). Most people are aware of a sudden exposure if there are soon-to-follow side effects. Chronic exposure frequently takes longer to identify because the toxins accumulate and symptoms may be non-existent or subtle for an extended period of time. Exposure time may or may not impact the seriousness of the effects.
Toxins, at one time, were largely thought about solely in reference to humans. However, toxicity occurs in plants, animals, and insects too. What is toxic for one species may not be for the other. For example, humans consume chocolate with pleasurable after-effects, whereas that same treat can kill a dog within hours. Human and canine metabolisms are not the same. Similarly, some non-caloric sweeteners are lifesavers to millions of diabetics but can be fatal to the family pooch.
Humankind exists and thrives in the same ecosystem as plants and animals. Species depletion can be a signal that an environment has become toxic, and effects may ripple through the food chain. The worldwide collapse of bee colonies in the twenty-first century may pose long-term consequences for humans. Bees are succumbing not only to virus and fungal manifestations, but also to toxic responses. Aluminum has been identified as one of those toxins. Without bees, a large percentage of plants, including agricultural crops, would not be pollinated.
Toxins may be ingested but they may also be airborne and breathed in. The toxic effects of pollution have taken a significant toll in two of the world’s largest cities in China and India. Smog has reached such toxic levels that cars are banned from those cities at least twice a week. The number of cases of asthma and other lung diseases has soared in areas of poor air quality.
According to the US Environmental Protection Agency (EPA), 17,000 facilities throughout the United States emit toxins that contaminate the surrounding environment at varying levels. Toxins are frequently the byproduct of industries that provide useful, desirable, and even necessary goods, such as energy and pharmaceuticals. Toxins may also be found in the goods themselves, requiring proper disposal. An example is plastic grocery bags. Proper disposal and recycling can make them cost-effective and environmentally neutral; however, millions are dumped in the ocean or washed out to sea where they become toxic polymers in seawater as they break down.
Bibliography
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