Harmful substances in Food and the Environment

Toxins are found in a wide range of foods and water. They are usually contaminants present in the food when purchased or created when cooking.

Be mindful that many products on UK shelves originate in other countries where pesticides banned in the UK and Europe are still used. This is of particular issue with regard to foods that originate in India, China, Africa and the USA (all of which use banned pesticides in their food chain and may also contain levels of heavy metals that exceed UK safety levels)

Toxins Found in Food

Natural Toxins

- Lectins: Found in raw beans (especially red kidney beans), can cause gastrointestinal distress2 3 4.
- Solanine & Chaconine (Glycoalkaloids): Present in green or sprouting potatoes and green tomatoes; can cause nausea, diarrhea, confusion, or more severe effects2 3.
- Cyanogenic Glycosides: Found in cassava, sorghum, stone fruit seeds, and bitter almonds; can release cyanide if improperly processed3 4.
- Furocoumarins: Present in parsnips, celery roots, and citrus plants; can cause skin reactions and gastrointestinal issues3.
- Amygdalin: Found in bitter almonds and stone fruit pits; can release cyanide in the body2 4.
- Mycotoxins (e.g., Aflatoxins, Ochratoxin A): Produced by molds on grains, nuts, dried fruits, and spices; can be carcinogenic and cause liver or kidney damage3 5 8.
- Hypoglycin A: Found in unripe ackee fruit; can cause vomiting, coma, or death4.
- Grayanotoxins: Found in honey from certain plants; can cause "mad honey" poisoning4.
- Mushroom Toxins: Present in certain wild mushrooms; can cause a range of symptoms from nausea to death4.
Environmental and Industrial Contaminants

- Heavy Metals (e.g., Lead, Cadmium, Mercury): Accumulate in certain foods from soil, water, or pollution5 8.
- Pesticides: Residues can remain on fruits, vegetables, and grains8.
- Bisphenol A (BPA) and Phthalates: Found in some packaged foods due to plastic contamination8.
- PFAs (Per- and Polyfluoroalkyl Substances): Contaminate some foods through environmental exposure8.
- Nitrates and Nitrites: Naturally occurring or added to processed meats; can form harmful compounds in the body8.

Toxins Formed or Released After Cooking

Heterocyclic Amines (HCAs): Formed when meat is cooked at high temperatures (grilling, frying)1.
Polycyclic Aromatic Hydrocarbons (PAHs): Produced when fat drips onto hot surfaces during grilling or smoking1.
Acrylamide: Forms in starchy foods cooked at high temperatures (frying, roasting, baking), especially from the Maillard reaction1.
Advanced Glycation End-products (AGEs): Formed when sugars react with proteins or fats at high temperatures1.
Oxidized Fats and Aldehydes: Generated when oils are heated to high temperatures, especially polyunsaturated oils1.
Trans Fats: Can form when oils are repeatedly heated or during industrial hydrogenation (now banned in many countries)1.
Nitrosamines: Can form in cured meats during cooking, especially at high temperatures.

Summary Table

Toxin Type	Found When Purchased	Formed/Released After Cooking
Lectins	Yes	No (destroyed by cooking)
Solanine/Chaconine	Yes	No (levels may be reduced)
Cyanogenic Glycosides	Yes	No (destroyed by processing)
Furocoumarins	Yes	No
Amygdalin	Yes	No (destroyed by processing)
Mycotoxins	Yes	No (mostly stable)
Hypoglycin A	Yes	No (reduced by processing)
Grayanotoxins	Yes	No
Fungal Toxins	Yes	No
Heavy Metals	Yes	No
Pesticides	Yes	No
BPA/Phthalates	Yes	No
PFAs	Yes	No
Nitrates/Nitrites	Yes	No (but can form nitrosamines)
HCAs	No	Yes
PAHs	No	Yes
Acrylamide	No	Yes
AGEs	No	Yes
Oxidized Fats/Aldehydes	No	Yes
Trans Fats	Sometimes	Yes (can form during heating)
Nitrosamines	No	Yes (from nitrates/nitrites)

This list highlights the main toxin types encountered in food, both before and after cooking.

You can find more information about each of them by going to the list of major contaminants and their health risks.