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Metals in Food

Food can contain a wide range of metallic elements (metals) such as sodium, potassium, iron, calcium, magnesium, copper and zinc. These metals in trace quantities are essential in the human diet for normal bodily functions.

However, other metallic elements (referred to as “metals” from here on) have no functional effects in the body and can be harmful to health if foodstuffs containing them are consumed regularly in the diet. The majority of all metals are natural components of the earth’s crust. Metals and other elements can be naturally present in food due to their uptake from the environment or can enter food as a result of human activities such as industrial and agricultural processes.

The metals of particular concern in relation to harmful effects on health are: Mercury (Hg), Lead (Pb), Cadmium (Cd), Tin (Sn), Nickel (Ni) and Arsenic (As).

Questions and answers about each metal

  • Mercury

    Is mercury dangerous to consumers?

    Yes, excessive exposure to mercury is associated with several adverse health effects including damage to the central nervous system (neurotoxicity) and the kidneys. 

    There are two forms of mercury, organic and inorganic, and the organic form methylmercury is more toxic. The main concern for methylmercury is potential neurotoxicity in young children. Organic forms of mercury can potentially pass from the mother to the unborn baby through the placenta, and if exposure is high enough can cause adverse effects on the developing brain. 

    What are the sources of exposure to Mercury in food?

    Contamination of food with mercury arises from the natural presence of mercury in the environment and due to human activities, including mining, industrial processes, and burning of fossil fuels.

    Mercury exposure mainly occurs through dietary sources, where it is evenly distributed in food at very low concentrations, as well as through dental amalgam (i.e. fillings). 

    The main sources of mercury in the diet are fish, particularly predatory fish species (e.g. shark, swordfish, marlin and tuna), other fish such as cod and whiting, and shellfish (molluscs and crustaceans). 

    What dietary advice does the FSAI have for pregnant and breastfeeding women, women of childbearing age and young children?

    Due to the high levels of mercury in predatory fish, the FSAI advises pregnant and breastfeeding women, women of childbearing age and young children to avoid consumption of shark, swordfish and marlin, and to limit their intake of tuna steak and canned tuna, while continuing to consume other fish as part of a balanced diet. More information is available on the FSAI’s webpage on Mercury and Fish Consumption and the Healthy Eating Guidelines. 

    What should food businesses do to limit Mercury in foods?

    All food businesses, i.e., food business operators, have a legal responsibility under the General Food Law (Regulation (EC) No 178/2002) to ensure the food they place on the market is safe and complies with all relevant legal requirements.

    The implementation of a food safety management system based on the principles of Hazard Analysis and Critical Control Point (HACCP) is also a legal requirement for most food businesses under Article 5 of Regulation (EC) No 852/2004.

    A HACCP system enables hazards such as mercury to be identified and controlled by the food business, before they become a food safety issue. In that regard, in those food businesses where mercury have been identified as a hazard, it must be ensured that food placed on the market complies with the maximum levels for mercury. These maximum limits are laid down in the following legislation depending on the food type: 

    • Regulation (EU) 2023/915 establishes maximum levels for mercury in the muscle meat of fish, bivalve molluscs, crustaceans, food supplements and salt.
    • Regulation (EC) No 396/2005 establishes maximum residue levels for various mercury compounds used in pesticides which are not authorised for use in the European Union. The maximum residue level is established at a level which is not quantifiable by laboratories in the European Union.
    • Commission Delegated Regulation (EU) 2016/128 establishes a maximum residue level for mercury compounds in food for special medical purposes to protect against its unauthorised use in pesticides. The maximum residue level is established at a level which is not quantifiable by laboratories in the European Union.
    • Commission Directive 2006/125/EC establishes a maximum residue level for mercury compounds in processed cereal-based foods and baby foods for infants and young children to protect against its unauthorised use in pesticides. The maximum residue level is established at a level which is not quantifiable by laboratories in the European Union.
    • Commission Regulation (EU) No 231/2012 establishes maximum levels for mercury in specific food additives.
    • Regulation (EC) No 853/2004 establishes maximum levels for mercury in gelatine and collagen.
    • Commission Implementing Regulation (EU) No 1321/2013 establishes maximum levels for mercury in smoke flavourings.
    • Commission Implementing Regulation (EU) 2017/2470 establishes maximum levels for mercury in novel foods.

    How are foods sampled and monitored for Mercury?

    There are detailed rules provided in Regulation (EC) No 333/2007 for the sampling and analysis of foods for mercury. These rules include the sampling procedures to be followed by those taking the samples, the precautions to be taken during sampling and the methods of analysis to be used in the laboratories.

    How do you minimise the presence and level of Mercury in food?

    Mercury can accumulate in food from the environment during the early stages of production. For consumers, there are few options to reduce the levels of the mercury during preparation and cooking. 

    In general, consumers can lower their exposure to mercury by eating a healthy and balanced diet. 

    Some specific measures to reduce exposure to mercury in food includes:

    • Avoid regularly consuming food known to contain high levels of mercury. For example, predatory fish such as shark, swordfish and marlin. It is particularly important to avoid consuming fish known to contain high levels of mercury if you are pregnant or breastfeeding. Maximum levels are established in legislation to encourage the application of good practices by industry, to remove contaminated food from sale and protect consumers.
    • If you have a private drinking water supply, it is recommended to test the water annually for heavy metals to ensure it does not contain excessive levels.

  • Lead

    Is lead dangerous to consumers?

    Yes, the toxic effects of lead are a consequence of its accumulation in the body, particularly in the skeleton. Even after lead exposure has ended, it is progressively released back into the bloodstream from the skeleton, particularly during physiological or pathological phases of bone demineralisation such as pregnancy, lactation and osteoporosis. 

    Lead can be transferred from the mother to the unborn baby and through breast milk. 

    Lead affects virtually every system in the body, including the blood, the cardiovascular, renal, endocrine, gastrointestinal, immune and reproductive systems. The critical target for lead toxicity is the central nervous system (CNS), particularly the developing brain, where it has the potential to cause impaired cognitive development and intellectual performance in children even at low exposure levels.

    What are the sources of exposure to lead in food?

    Food and water represent the major sources of exposure to lead for the general population. Lead contamination of food and water arises as a result of industrial releases to the environment, such as from mining, smelting, battery manufacturing and the now diminished use of leaded petrol.

    The main sources of lead in the diet are alcoholic drinks, cereals, vegetables (particularly potatoes and leafy vegetables) and tap water.

    High levels can be found in fish and shellfish, and in edible offal such as liver and kidneys.

    Other sources of lead in the diet can be from water distributed in old lead water pipes or from food containers containing lead, e.g. ceramic vessels with lead glazes and leaded crystal glass.

    What should food businesses do to limit lead in foods?

    All food businesses, i.e., food business operators, have a legal responsibility under the General Food Law (Regulation (EC) No 178/2002) to ensure the food they place on the market is safe and complies with all relevant legal requirements.

    The implementation of a food safety management system based on the principles of Hazard Analysis and Critical Control Point (HACCP) is also a legal requirement for most food businesses under Article 5 of Regulation (EC) No 852/2004.

    A HACCP system enables hazards such as lead to be identified and controlled by the food business, before they become a food safety issue. In that regard, in those food businesses where lead have been identified as a hazard, it must be ensured that food placed on the market complies with the maximum levels for lead. These maximum limits are laid down in the following legislation depending on the food type: 

    How are foods sampled and monitored for Lead?

    There are detailed rules provided in Regulation (EC) No 333/2007 for the sampling and analysis of foods for lead. These rules include the sampling procedures to be followed by those taking the samples, the precautions to be taken during sampling and the methods of analysis to be used in the laboratories.

    How do you minimise the presence and level of Lead in food?

    Lead can accumulate in food from the environment during the early stages of production. Lead can also occur in drinking water due to the distribution of water in lead pipes. For consumers, there are few options to reduce the levels of the lead during preparation and cooking. 

    In general, consumers can lower their exposure to lead by eating a healthy and balanced diet. 

    Some specific measures to reduce exposure to lead in food includes:

    • Avoid regularly consuming food known to contain high levels of lead mentioned in the section on sources of exposure to lead in food. Maximum levels are established in legislation to encourage the application of good practices by industry, to remove contaminated food from sale and protect consumers.
    • Following the manufacturer’s instructions for care and use of food contact materials provided on the label.
    • Limiting their use of ceramic vessels with lead glazes and leaded crystal glass.
    • If you have a private drinking water supply, it is recommended to test the water annually for heavy metals to ensure it does not contain excessive levels.

  • Cadium

    Is cadmium dangerous to consumers?

    Yes, cadmium is primarily toxic to the kidneys. Accumulation of cadmium in the kidneys over time may cause renal dysfunction or even renal failure. Cadmium can also cause bone demineralisation, either through direct bone damage or indirectly as a result of renal dysfunction.

    What are the sources of exposure to cadmium in food?

    Cadmium is present at low levels in most foods, with commodities such as cereals, fruit, vegetables, meat and fish making the largest contribution to dietary exposure.

    Highest levels of cadmium can be found in the seaweed and seaweed formulations, cocoa-based products, crustaceans, edible offal, mushrooms, oilseeds and molluscs.

    Cadmium exposure can also occur via smoking or occupational exposure. For the non-smoking general population, food is the main source of exposure.

    What should food businesses do to limit cadmium in foods?

    All food businesses, i.e., food business operators, have a legal responsibility under the General Food Law (Regulation (EC) No 178/2002) to ensure the food they place on the market is safe and complies with all relevant legal requirements.

    The implementation of a food safety management system based on the principles of Hazard Analysis and Critical Control Point (HACCP) is also a legal requirement for most food businesses under Article 5 of Regulation (EC) No 852/2004.

    A HACCP system enables hazards such as cadmium to be identified and controlled by the food business, before they become a food safety issue. In that regard, in those food businesses where cadmium have been identified as a hazard, it must be ensured that food placed on the market complies with the maximum levels for cadmium. These maximum limits are laid down in the following legislation depending on the food type: 

    How are foods sampled and monitored for cadmium?

    There are detailed rules provided in Regulation (EC) No 333/2007 for the sampling and analysis of foods for cadmium. These rules include the sampling procedures to be followed by those taking the samples, the precautions to be taken during sampling and the methods of analysis to be used in the laboratories.

    How do you minimise the presence and level of Cadmium in food?

    Cadmium can accumulate in food from the environment during the early stages of production. For consumers, there are few options to reduce the levels of the cadmium during preparation and cooking.

    In general, consumers can lower their exposure to cadmium by eating a healthy and balanced diet. 

    Some specific measures to reduce the amount of cadmium present in food includes:

    • Avoid regularly consuming food known to contain high levels of cadmium mentioned in the section on sources of exposure to cadmium in food. Maximum levels are established in legislation to encourage the application of good practices by industry, to remove contaminated food from sale and protect consumers.
    • Following the manufacturer’s instructions for care and use of food contact materials provided on the label.
    • Peeling fruit and vegetables can reduce levels, as cadmium accumulates in the peel. For example, peeling potatoes or carrots before eating.
    • If you have a private drinking water supply, it is recommended to test the water annually for heavy metals to ensure it does not contain excessive levels.

     
     

  • Arsenic

    Is arsenic dangerous to consumers?

    Yes, long-term exposure to inorganic arsenic (i.e. the most toxic form of arsenic compared to organic forms) has been associated with cancers of the skin, bladder and lung; skin lesions, cardiovascular diseases, respiratory disease, chronic kidney disease, neurodevelopmental effects, infant mortality and effects on unborn babies (e.g. lower birth weight, spontaneous abortion, stillbirth). Arsenic can also have short term toxic effects at high doses.

    What are the sources of exposure to arsenic in food?

    Arsenic is a naturally occurring element, present in soil, ground water and plants. 

    The main sources of total arsenic in the diet are fish and seafood.
    The main sources of inorganic arsenic in the diet are rice and rice products, grain and grain products and drinking water.

    What dietary advice does the FSAI have related to arsenic?

    The FSAI has advice on the consumption of hijiki seaweed due to the high levels of inorganic arsenic that can be naturally present. The FSAI advises consumers to limit their consumption of hijiki seaweed or choose alternative types of seaweed, where possible.

    The FSAI has advice warning against using rice milk for infants and young children due to the presence of low levels of inorganic arsenic arsenic. 

    What should food businesses do to limit arsenic in foods?

    All food businesses, i.e., food business operators, have a legal responsibility under the General Food Law (Regulation (EC) No 178/2002) to ensure the food they place on the market is safe and complies with all relevant legal requirements.

    The implementation of a food safety management system based on the principles of Hazard Analysis and Critical Control Point (HACCP) is also a legal requirement for most food businesses under Article 5 of Regulation (EC) No 852/2004.

    A HACCP system enables hazards such as arsenic to be identified and controlled by the food business, before they become a food safety issue. In that regard, in those food businesses where arsenic have been identified as a hazard, it must be ensured that food placed on the market complies with the maximum levels for arsenic. These maximum limits are laid down in the following legislation depending on the food type: 

    How are foods sampled and monitored for arsenic?

    There are detailed rules provided in Regulation (EC) No 333/2007 for the sampling and analysis of foods for inorganic arsenic. These rules include the sampling procedures to be followed by those taking the samples, the precautions to be taken during sampling and the methods of analysis to be used in the laboratories.

    How do you minimise the presence and level of arsenic in food?

    Arsenic can accumulate in food from the environment during the early stages of production. For consumers, there are few options to reduce the levels of the arsenic during preparation and cooking. 

    In general, consumers can lower their exposure to Arsenic by eating a healthy and balanced diet. 

    Some specific measures to reduce exposure to arsenic in food includes:

    •    Avoid regularly consuming food known to contain high levels of arsenic mentioned in the section on sources of exposure to arsenic in food. Maximum levels are established in legislation to encourage the application of good practices by industry, to remove contaminated food from sale and protect consumers.
    •    Washing or soaking rice before cooking, or cooking rice in an excess of water.
    •    Peeling fruit and vegetables can reduce levels, as arsenic accumulates in the peel.
    •    If you have a private drinking water supply, it is recommended to test the water annually for heavy metals to ensure it does not contain excessive levels.

  • Nickel

    Is nickel dangerous to consumers?

    Yes, long term exposure to nickel can cause effects on the gastrointestinal, haematological (i.e. blood), neurological and immune systems. Short-term exposure to high levels of nickel can result in gastrointestinal and neurological symptoms. Nickel exposure via food or drinking water can trigger eczematous flare-up reactions in nickel-sensitized individuals.

    What are the sources of exposure to nickel in food?

    Nickel is widely distributed in nature and is present in water, soil, plants and animals. Exposure to nickel for the general non-smoking population is primarily from food and to a lesser extent via drinking water.

    The main sources of Nickel in the diet is from grain and grain-based products, beans, coffee, ready-to-eat soups, chocolate and breakfast cereals.

    What should food businesses do to limit nickel in foods?

    All food businesses, i.e., food business operators, have a legal responsibility under the General Food Law (Regulation (EC) No 178/2002) to ensure the food they place on the market is safe and complies with all relevant legal requirements.

    The implementation of a food safety management system based on the principles of Hazard Analysis and Critical Control Point (HACCP) is also a legal requirement for most food businesses under Article 5 of Regulation (EC) No 852/2004.

    A HACCP system enables hazards such as nickel to be identified and controlled by the food business, before they become a food safety issue. In that regard, in those food businesses where nickel have been identified as a hazard, it must be ensured that food placed on the market complies with the maximum levels for nickel. These maximum limits are laid down in the following legislation depending on the food type: 

    • Regulation (EU) 2023/915 establishes maximum levels for nickel in nuts, vegetables, legumes, seaweed, cereals, cocoa and chocolate products, fruit juices, food for infants and young children.

    How are foods sampled and monitored for nickel?

    There are detailed rules provided in Regulation (EC) No 333/2007 for the sampling and analysis of foods for nickel. These rules include the sampling procedures to be followed by those taking the samples, the precautions to be taken during sampling and the methods of analysis to be used in the laboratories.

    How do you minimise the presence and level of nickel in food?

    Nickel can accumulate in food from the environment during the early stages of production. For consumers, there are few options to reduce the levels of the nickel during preparation and cooking. 

    In general, consumers can lower their exposure to nickel by eating a healthy and balanced diet.

    Some specific measures to reduce the amount of nickel in food includes:

    • Avoid regularly consuming food known to contain high levels of nickel mentioned in the section on sources of exposure to nickel in food.


     

  • Tin

    Is tin dangerous to consumers?

    Tin is relatively less toxic than mercury, cadmium and lead. In humans, gastrointestinal effects are the main acute toxic effects associated with ingestion of tin and scientific evidence suggests that these effects occur when concentrations of tin are above 250 mg/kg in canned foods and 150 mg/kg in canned beverages. Maximum levels are established in the European Union for canned foods, beverages and foods intended for infants and young children to protect against tin toxicity.

    What are the sources of exposure to Tin in food?

    Tin is used by the food industry as a coating for cans to prevent corrosion. 

    Food and beverages contained in tin-plated cans are the main source of exposure to tin. The release of tin from the cans into food can be higher if the cans are used to store acidic food and beverages or for long storage times and at high temperatures.

    High levels of tin can be found in food stored in incorrectly manufactured or damaged tin-plated cans.

    What should food businesses do to limit tin in foods?

    All food businesses, i.e., food business operators, have a legal responsibility under the General Food Law (Regulation (EC) No 178/2002) to ensure the food they place on the market is safe and complies with all relevant legal requirements.

    The implementation of a food safety management system based on the principles of Hazard Analysis and Critical Control Point (HACCP) is also a legal requirement for most food businesses under Article 5 of Regulation (EC) No 852/2004..

    A HACCP system enables hazards such as tin to be identified and controlled by the food business, before they become a food safety issue. In that regard, in those food businesses where tin have been identified as a hazard, it must be ensured that food placed on the market complies with the maximum levels for tin. These maximum limits are laid down in the following legislation depending on the food type: 

    • Regulation (EU) 2023/915 establishes maximum levels for inorganic tin in a canned food and beverages, including canned baby food, processed cereal-based food and food for special medical purposes intended for infants and young children.

    How are foods sampled and monitored for tin?

    There are detailed rules provided in Regulation (EC) No 333/2007 for the sampling and analysis of foods for inorganic tin. These rules include the sampling procedures to be followed by those taking the samples, the precautions to be taken during sampling and the methods of analysis to be used in the laboratories.

    How do you minimise the presence and level of tin in food?

    Tin occurs in food as a result of its release from tin coated cans into the food.
    In general, consumers can lower their exposure to tin by eating a healthy and balanced diet.  
    Some specific measures to reduce the amount of tin in food includes:

    • Transferring any left-over food from opened cans into other containers (e.g. glass, plastic) for storage, as tin can transfer to the food when exposed to air.
    • Choosing lacquered cans were possible, as the internal lining significantly reduces tin leaching into food. 
    • Do no re-use cans. For example, for storing food or use as baking tins. 

    Maximum levels are established in legislation to encourage the application of good practices by industry, to remove contaminated food from sale and protect consumers.