What are they? How do they get into our food? How can they affect health?
Heavy metals and metalloids, often collectively referred to as heavy metals, are compounds found in the environment, including air, water, and soil. They can be present at various levels in the environment, e.g. soil, water and atmosphere. Metals can also occur as residues in food because of their presence in the environment, as a result of human activities such as farming, industry or car exhausts, or from contamination during food processing and storage.
The list of heavy metals includes, among others:
- arsenic
- cadmium
- lead
- mercury (including inorganic mercury)
- inorganic tin
- chromium
- uranium
Various factors, ranging from environmental conditions during growth to post-harvest handling, processing, preparation, and cooking techniques, influence the toxic metal content in foods.
Factors that can impact heavy metal concentrations include:
- How foods grow: Root vegetables grow in soil, so they absorb more heavy metals than vegetables grown above ground.
- A plant’s biology: Sometimes, it depends on the make-up of the plant itself. Rice, for example, is more likely to absorb arsenic, while onions are more likely to absorb lead.
- The food chain: A plant, animal, or living organism’s position on the food chain can affect its heavy metal concentration. When it comes to our oceans, fish at the top of the food chain, like tuna, can accumulate mercury more than algae, which is at the bottom.
EU food contaminant legislation sets maximum allowable levels for various impurities in food products. To guarantee product safety, these levels are set to be “as low as reasonably achievable” by following good agricultural and manufacturing practices.
People can be persistently exposed to heavy metals from the environment or by ingesting contaminated food or water. Their bio-accumulation in the body can lead to harmful effects over time. This is because heavy metals have toxicity at low concentrations due to their relatively high density. They have no established health benefits and can cause illness and health impairments.
Ingestion of heavy metals can affect prevent the absorption of other beneficial metals like magnesium, iron, calcium, and zinc.
Symptoms of Heavy Metal Accumulation
Symptoms of toxic heavy metal exposure, from food or other sources, may include:
- Chronic inflammation
- Fatigue
- Insomnia and sleep issues
- Digestive issues
- Brain fog and cognitive complaints
- Headaches or migraines
- Mood swings
- Anxiety and depression
- Muscle and joint pain
- High or low blood pressure
- Skin issues
- Autoimmunity
Extra info:
French doctors raised concerns about the health effects of a toxic heavy metal found in everyday food staples such as bread, cereal, pasta and potatoes.
Cadmium, which causes cancer in humans, is naturally found in soil and used in phosphate fertilisers, meaning it is introduced to the food chain through crops. Food is most people’s top source of exposure, though cigarettes also contain cadmium.
Cadmium has been linked to pancreatic, lung, prostate, and kidney cancers, as well as heart diseases, fertility problems, kidney damage, neurological issues, and bone disorders.
In June 2025, the French association of medical professionals (URPS) says there is an “explosion of contamination of young children” because of their diets, with likely health consequences as they grow up.
“The metal is considered one of the most toxic in existence,” according to the doctors’ letter to the French government.
In France, 0.6 per cent of adults’ diets are too high in cadmium. This rises to 14 per cent for children aged three to 17, and up to 36 per cent for toddlers under the age of three.
According to a Italy reported the most alerts for cadmium contamination in the European Union, followed by Spain, Germany, France, and Poland,
https://www.efsa.europa.eu/en/topics/topic/metals-contaminants-food
