Introduction:
Natural toxins are formed in food due to the defense mechanisms of plants through infestation through ingestion by animal toxins. They can cause various adverse effects and serious health threats to livestock and humans. Some of the natural toxins are extremely potent. Adverse health issues can be acute poisoning that ranges from allergic reactions to severe diarrhea (refers to watery loose stool more than two times a day) and stomach aches. Therefore, people should follow the conventional safe ways of food processing and maintain a varied and balanced diet so that exposure to different types of natural toxins can be kept to safe levels.
What Are Natural Toxins?
Natural toxins are compounds that are produced naturally by living organisms. These toxins do not harm organisms but can be toxic to humans when eaten. These chemical compounds differ in biological function and have diverse structures. For example, the plant produces specific toxins as a natural defense against insects, microorganisms, and predators. Other sources associated with natural toxins are plankton and microscopic algae in oceans and lakes that produce chemical compounds toxic to humans but not to shellfish and fish that contain toxins and cause illness.
Where Do Natural Toxins Come From?
A variety of plants and animals produces toxins. Natural toxins present serve specific functions in animals or plants or evolve as chemical defenses against insects, predators, or microorganisms. Natural toxins are found in foods of animal and plant origin and can be harmful when consumed in various quantities.
What Are the Different Types of Toxins?
The different types of toxins are as follows:
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Aquatic Biotoxins: Toxins formed by algae in freshwater and ocean are called algal toxins. Algal toxins are produced during blooms of naturally occurring algal species. Shellfish such as scallops, oysters, and mussels are more likely to contain these toxins than fish. They can cause tingling, paralysis, and diarrhea (refers to watery loose stool more than two times a day). The algal toxins can be retained in fish and shellfish or contaminate the drinking water. They have no smell or taste and are eliminated by freezing or cooking.
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Another example is ciguatera fish poisoning (CFP) caused by consuming contaminated fish. Symptoms of ciguatera poisoning include vomiting, nausea, and neurological symptoms such as sensation on the finger and toes and tingling. There is no specific treatment available for ciguatera poisoning.
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Cyanogenic Glycosides: They are toxic chemicals produced by plants that can be seen in at least 2000 plant species. Sorghum, cassava, bamboo roots, almonds, or stone fruit contain cyanogenic glycosides. The toxicity of cyanogenic plants depends on the potential of their consumption. The clinical signs of acute cyanide toxicity include a drop in blood pressure, mental confusion, dizziness, rapid respiration, and diarrhea. Death due to cyanide poisoning occurs only when cyanide levels are exceeded beyond the limits.
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Furocoumarins: These toxins are mainly present in many plants, such as celery roots, citrus plants (lime, lemon, bergamot, and grapefruit), and some medicinal plants. They are also called stress toxins and are produced in response to stress, such as physical damage to the plant. Some toxins can even cause gastrointestinal problems in humans. Furocoumarins are generally phototoxic and cause skin reactions under sunlight.
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Lectins: Many beans contain toxins known as lectins. These lectins can cause vomiting, diarrhea, and stomach ache. Lectins can be destroyed when beans are soaked for at least 12 hours and boiled for about ten minutes in water.
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Mycotoxins: They are naturally occurring toxic compounds produced by mold. The mold that produces mycotoxin grows on foodstuffs such as dried fruits, nuts, spices, and cereals. Mold growth can occur after or before the harvest. Most mycotoxins survive food processing and are chemically stable.
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Solanine and Chaconine: All solanaceous plants, including potatoes, tomatoes, and eggplant, contain toxins called solanine and chaconine. These plants produce toxins in response to stress, such as microorganisms, bruising, attacks from insect herbivores, and pesticides. To reduce the formation of solanine and chaconine, it is important to store potatoes in cool, dry, and dark places and avoid eating sprouting or green parts.
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Poisonous Mushroom: Wild mushroom contains toxins, such as muscarine and muscimol, that causes diarrhea, vomiting, hypersalivation, visual disturbances, and hallucination. Symptoms begin after six to 24 hours after the consumption of mushrooms. Fatal poisoning is associated with delayed onset of symptoms that affects the kidney, nervous system, and liver.
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Pyrrolizidine Alkaloids: These are toxins produced by 600 plant species. The main plant sources are the families Asteraceae, Boraginaceae, and Fabaceae. It can lead to a variety of adverse health effects that have the potential even to cause cancer.
How to Reduce the Exposure to Natural Toxins?
Different methods of food processing and cooking can help reduce or destroy the toxin levels.
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In other cases, the toxins cannot be removed or reduced; intake should be limited.
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Cooking helps to destroy the lectin of beans and enzyme inhibitors.
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Soaking followed by boiling in water also helps remove cyanide-generating compounds.
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Removal of skin, gonads and other parts of certain fish eliminates toxins concentrated in tissue.
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Oysters, mussels, and clams should be purchased from hygienic shops.
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Harvesting of tropical reef fish and shellfish should be done cautiously.
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Seafood should be kept below 40 degrees Fahrenheit using ice or adequate refrigeration.
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Antioxidant-rich food should be added to the diet of a person.
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An adequate quantity of water should be consumed for the natural removal of toxins.
Conclusion:
Food is one of the sources of nutrients for humans. Natural toxins are present in animals and plants. They are chemicals produced by living organisms like fungi, bacteria, plants, animals, and algae. Some food contains harmful natural toxins, which lead to adverse human reactions and can have carcinogenic effects. Naturally occurring plant toxins usually disrupt metabolic processes by blocking certain enzymes. Therefore, proper hygiene and eating habits should always be promoted.
