Undesirables in Food: Toxins Overview

A bitter, heat-stable glycoalkaloid found in potatoes and eggplants. It can build up in potatoes exposed to sunlight, turning them green, and is concentrated just under the skin.

Solanine inhibits the action of acetylcholinesterase, a crucial enzyme in the nervous system.

Stimulants found in tea, coffee, cocoa, and cola beverages.

The caffeine content of roasted coffee beans is around 1-2%, varying depending on the brewing method.

Black tea leaves contain 3-4% caffeine, resulting in approximately 50mg per cup.

Cocoa powder contains 2% theobromine and 0.2% caffeine, with levels varying in different chocolate types.

Cola drinks are restricted to 200mg/L of caffeine, with most containing around 65mg/L. Energy drinks often include extracts of Guarana for even higher caffeine levels, reaching 200-300mg/L.

Caffeine stimulates the release of adrenaline and noradrenaline, leading to various effects on glucose, triglycerides, and cholesterol levels in the blood.

Pyrrolizidine alkaloids (PAs) are naturally occurring toxins found in certain plants, like comfrey, which can contaminate milk and honey if animals or bees ingest them. They have been linked to liver damage, especially when consumed in herbal remedies.

Psoralens are natural substances with insecticidal properties found in plants like celery. They can cause severe skin rashes in those who work closely with them, particularly when absorbed through the skin from the plant's green parts.

Phenylethylamine is a vasopressor amine found in chocolate, cheese, and wine. It can cause migraine headaches in susceptible individuals by constricting blood vessels, potentially leading to hypertension.

Cyanogenesis is a process that releases cyanide, a toxic compound, from plants like cassava. Chronic exposure to low levels of cyanide through cassava consumption can cause severe health problems.

Cassava, a starchy root vegetable, contains cyanogenic glycosides, which release cyanide when ingested. Chronic exposure to low levels of cyanide from cassava can lead to serious health issues. Two common diseases associated with cyanide exposure from cassava are degenerative neurological conditions and a form of blindness.

Raw legumes, such as peas, beans, peanuts, and soybeans, contain two main types of toxins: (1) lectins, which are proteins that can interfere with intestinal absorption and cause digestive problems, and (2) antinutritional factors, which can inhibit the absorption of nutrients and lead to nutrient deficiencies.

Decaffeinated instant coffee is a safer alternative for pregnant women compared to caffeinated coffee. While caffeine itself doesn't cause birth defects or low birth weights, its stimulant effects are not beneficial during pregnancy.

Certain plant foods contain naturally occurring toxins, also called endogenous toxins. These substances can have adverse effects on humans and are often present in the plant's defense mechanisms against insects or other organisms.

A group of toxins produced by the fungus Aspergillus flavus. One of the most potent liver carcinogens known, particularly dangerous in peanuts and peanut butter.

Aflatoxins are toxic to the liver. Long-term exposure can lead to liver damage, cancer, and hepatitis B.

Aflatoxins can be found in milk due to contaminated animal feedstuffs.

Aflatoxin B1 and G1 are converted into M1 by liver enzymes, appearing in milk and posing a serious problem for the dairy industry.

A mycotoxin found in warm climates that contaminates cereals. Associated with kidney disease in humans.

A mycotoxin that occurs in apple juice and home-made jam, indicating the use of moldy fruit. Not considered a dangerous toxin.

The most feared bacterial food poisoning caused by the toxin secreted by the anaerobic bacterium Clostridium botulinum.

The vegetative cells of Clostridium botulinum are not particularly resistant to heat, unlike its spores.

Proteins found in legumes that bind to red blood cells, causing them to clump together. This action is called hemagglutination.

A type of toxin found in plants, specifically soybeans. They mimic the effects of estrogen in the body.

A compound found in nutmeg and other spices. It can cause euphoria, hallucinations, and even nausea and delirium in large doses.

A toxin found in pufferfish, specifically in the liver and ovaries. It can cause paralysis and death, even at very low doses.

A toxin produced by red algae that can accumulate in shellfish. It causes a type of poisoning called Paralytic Shellfish Poisoning (PSP) and affects the nervous system.

A type of toxin commonly found in tuna and sardines. It is formed when the fish is not handled properly and stored at high temperatures.

Toxins produced by certain fungi that can contaminate food. They are often highly dangerous and can cause various health issues.

A disease caused by a mycotoxin called ergot, which contaminates grains like rye. It can cause severe health problems involving burning pain, loss of sensation, and mental derangement.

A specific form of mycotoxin that can cause ergotism.

The process of heating food to destroy harmful substances, such as toxins or bacteria. It is an essential part of food safety.

A neurotoxin produced by Clostridium botulinum bacteria, which blocks nerve impulses to muscles leading to paralysis and potentially death.

Contamination of food with Staphylococcus aureus toxin, which is heat-resistant and causes vomiting and diarrhoea.

An exaggerated immune response to a food component, leading to symptoms like skin reactions, vomiting, and breathing difficulties.

An immune response to proteins in wheat, barley, and rye, particularly the gliadin fraction of gluten.

A food allergen found in cow's milk, affecting up to 7% of infants.

A protein found in eggs, particularly ovomucoid, which can cause allergic reactions.

Chemicals used to control pests, which can contaminate food and pose health risks.

Heavy metals like lead, mercury, and cadmium, which can accumulate in food and harm human health.

The scientific study of food and its relationship to health, focusing on the chemical composition and effects on the body.

The process of breaking down food into smaller molecules that can be absorbed by the body. This involves mechanical and chemical processes.

Lead is a metal that can contaminate food and accumulate in our bodies over time. It's commonly found in old water pipes, leaded gasoline, and paints.

Mercury, often from industrial pollution or antifungal treatments, can contaminate seafood. Once in sediment, it turns into methylmercury, a highly toxic form.

PAHs, formed when food is cooked at high temperatures, are carcinogenic, meaning they can cause cancer. They are especially high in barbecued meat, where fat drips onto hot charcoal.

Plastics used for packaging can leach chemicals into our food. Plasticizers, like phthalates, can mimic hormones and affect fertility. BPA, used in certain plastics, is banned from baby bottles.

Dioxins, formed during the burning of materials containing chlorine, are persistent pollutants. They build up in fatty tissues and can harm our health.

PCBs, once used for various purposes, are now banned due to their toxic properties and persistence in the environment. They accumulate in fatty tissues, like dioxins.

The dirt on unwashed vegetables can carry bacteria and pathogens that cause foodborne illnesses.

Sewage sludge, when applied to crops, can introduce harmful bacteria and parasites. Fertilizers and other chemicals can also contaminate food.

Water used to process food, if contaminated, can introduce bacteria and other contaminants into the final product.

Equipment and utensils used in food processing, if not properly cleaned, can spread bacteria and other contaminants.