Metals as contaminants in food

Introduction

Metals such as arsenic, cadmium, lead and mercury are naturally occurring chemical compounds. 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. People can be exposed to these metals from the environment or by ingesting contaminated food or water. Their accumulation in the body can lead to harmful effects over time.

Latest

EFSA has updated a previous opinion on the risks to public health related to the presence of nickel in food and drinking water, taking into account new occurrence data, the updated benchmark dose guidance and new scientific information. The draft scientific opinion is currently under public consultation.

EFSA’s role

EFSA has received requests from the European Commission or Member States to provide risk assessments on several metals as contaminants, including arsenic, cadmium, chromium, lead, mercury, nickel and uranium. This work is carried out by the Panel on Contaminants in the Food Chain (CONTAM Panel). EFSA also works closely with Member States and other data providers to collect data on occurrence of metals in food and feed.

Milestones

February 2015 EFSA publishes a scientific opinion on the risks to human health from nickel in food, particularly in vegetables, and also in drinking water. EFSA sets a safe level, known as the tolerable daily intake (TDI), of 2.8 micrograms per kilogram of body weight. Experts conclude that current chronic dietary exposure to nickel is of concern for the general population.

January 2015 EFSA publishes a statement on the risks and benefits of seafood, specifically related to the presence of methylmercury in food. Limiting consumption of fish species with a high methylmercury content is the most effective way to achieve the health benefits of fish whilst minimising the risks posed by excessive exposure to methylmercury.

March 2014 EFSA updates its analysis of the occurrence of arsenic in food in Europe. The Authority’s data specialists refine their estimates of chronic (long-term) dietary exposure to inorganic arsenic, which were found to be lower than previously reported by EFSA.

March 2014 EFSA publishes a scientific opinion on the risk to human health from chromium in food, particularly in vegetables and in bottled drinking water. EFSA’s experts establish a tolerable daily intake (TDI) of 0.3 milligrams per kilogram of body weight per day for chromium III – which occurs naturally, is an essential nutrient and the main form of chromium present in food. Dietary exposure across all age groups is well below the TDI and therefore does not raise concerns for public health.

Animal studies indicate high levels of chromium VI can cause cancer; therefore, the Panel did not establish a safe level (‘TDI’) for chromium VI. Chromium VI is most commonly produced by industrial processes and is sometimes present in drinking water.

EFSA’s experts conclude there is a concern regarding average chromium VI intake via drinking water for infants, but a low concern for all other age groups. Above average exposures for some groups, particularly infants, toddlers and other children, could be a concern but these estimates are limited by the availability of data.

2011 Following an assessment of cadmium by the Joint FAO/WHO Expert Committee on Food Additives (JECFA), EFSA reassesses the TWI of 2.5 µg/kg bw established in 2009 and concludes that it is still appropriate.

The current average dietary exposure to cadmium for adults is close to the TWI and the exposure of some subgroups, such as children, vegetarians and people living in highly contaminated areas, could exceed the TWI. The risk of adverse effects for an individual at the current dietary exposure is low because the TWI is not based on actual kidney damage, but on an early indicator of changes in kidney function, suggesting possible kidney damage later in life. Experts reaffirm their previous conclusions that adverse effects are unlikely to occur in an individual at current dietary exposure but there is a need to reduce exposure to cadmium at the population level.

April 2010 EFSA publishes an opinion on possible health risks related to the presence of lead in food. Experts consider cereals, vegetables and tap water to contribute most to dietary exposure to lead for most Europeans. They conclude that current levels of exposure to lead pose a low to negligible health risk for most adults but there is potential concern over possible neurodevelopmental effects in foetuses, infants and children.

October 2009 EFSA adopts an opinion on arsenic in food, mainly focused on inorganic arsenic, which is the more toxic form in which arsenic can appear. Experts recommend that exposure to inorganic arsenic should be reduced.

March 2009 EFSA conducts a risk assessment on dietary exposure to uranium in foodstuffs, in particular mineral water, and advises on the TDI for uranium. The opinion focuses on the chemical toxicity of uranium.

EFSA concludes that average dietary exposure to uranium for the general population and high consumers across Europe is currently below the TDI. In specific areas where uranium concentrations in drinking water are high, the exposure estimates are close, but still below the TDI. For infants fed with infant formula made up with water containing uranium, exposure in relation to body weight may be up to three times higher than for adults.

EU framework

The principles of EU legislation on contaminants in food are contained in Regulation 315/93/EEC:

  • Food containing a contaminant to an amount unacceptable from the public health viewpoint, and in particular at a toxicological level, is not to be placed on the market.
  • Contaminant levels must be kept as low as can reasonably be achieved following recommended good working practices.
  • Maximum levels must be set for certain contaminants in order to protect public health.

Regulation EC 1881/2006 lays down maximum levels for certain contaminants in foodstuff, including lead, cadmium, mercury and inorganic tin. It does not cover radioactive substances. Regulation EC 333/2007 covers the methods of sampling and analysis for the official control of the maximum levels of these metals. Surveillance for residues of chemical elements in foods of animal origin is specified in Council Directive 96/23/EC.

See also

EU legislation on contaminants – European Commission