A toxin is simply a poison that can affect the body by internal or external means. A toxin can be a chemical which occurs naturally or in synthetic form. More than 120,000 human-made chemicals have been introduced into the environment, in one form or another, and this number continues to grow each year at a phenomenal rate. At the same time, microbial toxins, being influenced by the vast numbers of chemicals, are mutating beyond belief. Each category of microbes produces species that generates toxins in host cells. Evidence is proving a definitive link between the accumulation of toxins in body tissues and the development of chronic diseases.
External toxins, either chemical or microbial, enter the body through food, water, air, or physical contact with the skin or mucous membranes. Internal toxins, as the free radicals, are produced inside the body through normal metabolic processes or through the decomposition of foods in the small and large intestines. Bacterial toxins and yeast overgrowth can also form in cases of chronic constipation.
Under normal circumstances, the body is able to eliminate toxins from the body via urine, feces, exhalation, and persperation. Thus, the major organs involved in elimination are the kidneys, liver, colon, lungs, and skin. In addition, WBCs (white blood cells) of the immune system are designed to neutralize microbial toxins. The liver is the organ primarily responsible for breaking toxins into harmless byproducts, which are eliminated into the stool or through the kidneys into the urine.
The process of elimination can be hampered for one reason or another. When a particular toxin overwhelms the normal excretion mechanisms, the body produces inflammation in the area of the toxin trying to rid itself of the problem. These inflammatory areas signal the start of a disease. They are actually signals the body is sending, stating that it cannot rid itself of accumulating toxins. If the toxins remain, the body then moves into the next stage, where they are deposited in areas where they will do the least harm. These areas are usually fat cells, cysts, polyps or tumors. After years of storage, the toxins move into body cells and tissues. They ultimately produce such degenerative diseases as cancer, diabetes, arthritis, and heart disease.
A toxoid is a treated toxin, often used in vaccines, that retains its immunological structure, but which no longer causes damage to tissues. For example, the diphtheria toxoid is a sterile preparation of formaldehyde-treated products produced from the growth of Corynebacterium diphtheriae. It is generally mixed with the tetanus toxoid and pertussis in the DPT vaccine, but it can be used alone (DT). The same holds true for the tetanus toxoid produced from the growth of Clostridium tetani and used either by itself or in mixtures with diphteria toxoid and pertussis vaccine.
There are two general categories of toxins which differ in potency and function:
- Endotoxins, which are part of the cell wall of Gram-negative bacteria. Only small amounts may escape into surrounding fluids from living bacteria. Greater amounts are released when the bacteria die and their cell walls disintegrate. Endotoxins are less potent, and larger amounts are needed to induce disease symptoms. Also, they are heat resistant and cannot be converted into toxoids.
- Exotoxins are mainly proteins that are secreted by a bacterial cell into surrounding fluids, and are produced by both Gram-negative and Gram-positive bacteria. Most are readily destroyed by heat, but they can be converted into toxoids that are used as vaccines. Exotoxins are extrememly powerful biological poisons as in the case of tetanus, where it has been estimated that 1 mg of purified tetanus toxin could kill millions of mice.
Some examples of toxins include:
- Bacterial toxins are produced by bacteria that include exotoxins, endotoxins, interotoxins, neurotoxins, and toxic enzymes.
- Botulinus toxin is one of several type-specific exotoxins produced by Clostridium botulinum.
- Cholera toxin is an exotoxin produced by Vibrio cholerae, in which a protein enterotoxin stimulates cells in such a way as to cause severe diarrhea characteristic of the disease.
- Chlostridial toxin is one produced by species of Clostridium, which include those causing botulism, gas gangrene, and tetanus. In addition, C.difficile produces an exotoxin which causes severe intestinal necrosis. C.perfringens produces a number of potentially fatal exotoxins.
- Diptheria toxin is a protein exotoxin produced by Corynebacterium diphtheriae.
- Dysentry toxin is one produced by organisms of various species of Shigella.
- Erythrogenic toxin is a bacterial toxin from certain strains of Streptococcus pyogenes. Extracellular toxin is an exotoxin.
- Gas gangrene toxin is one of at least ten types of exotoxin produced by Clostridium perfringens. Intracellular toxin is endotoxin.
- Streptococcal toxin is a mixture of exotoxins formed by Streptococcus pyogenes.
- Tetanus toxin is a potent exotoxin produced by Clostridium tetani, consisting of two components, one a neurotoxin (tetanospasmin) and the other a hemolysin (tetanolysin).