Dioxins and PCBs

Dioxins and polychlorinated biphenyls (PCBs) are toxic chemicals that persist in the environment and accumulate in the food chain. Their presence in the environment in Europe has declined since the 1970s, following concerted efforts by public authorities and industry.

In the context of EFSA’s work, ‘dioxins’ refers to two groups of compounds: Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs). Dioxins have no technological or other use, but are generated in a number of thermal and industrial processes as unwanted and often unavoidable by-products. PCBs had widespread use in numerous industrial applications, and were produced in large quantities for several decades with an estimated total world production of 1.2-1.5 million tonnes, until they were banned in most countries by the 1980s.

Dioxins and PCBs are found at low levels in many foods. Longer-term exposure Concentration or amount of a particular substance that is taken in by an individual, population or ecosystem in a specific frequency over a certain amount of time. to these substances has been shown to cause a range of adverse effects on the nervous, immune and endocrine systems, and impair reproductive function. They may also cause cancer. Their persistence Persistence refers to the ability of harmful organisms like bacteria to survive and thrive despite regular cleaning and disinfection efforts, potentially lingering in hidden places for months or even years. and the fact that they accumulate in the food chain, notably in animal fat, therefore continues to cause some safety concerns.

Dioxins and some PCBs referred to as dioxin-like PCBs (due to their similar toxicological properties) are often considered together within the context of public health. Other PCBs referred to as ‘non dioxin-like PCBs’ have a different mechanism of toxicity The specific sequence of events explaining how a substance causes a toxic effect. but can also cause adverse effects on health.

Latest

The Panel on Contaminants in the Food Chain (CONTAM) completed EFSA’s first comprehensive review of the risks to human and animal health from dioxins and dioxin-like PCBs in food and feed. The experts reduced the tolerable weekly intake The maximum intake of substances in food, such as nutrients or contaminants, that can be consumed weekly over a lifetime without risking adverse health effects. seven-fold based on new data and methods. They concluded that dietary exposure For the purposes of risk assessment, measurement of the amount of a substance consumed by a person or animal in their diet that is intentionally added or unintentionally present (e.g. a nutrient, additive or pesticide). to dioxins and dioxin-like PCBs is a health concern as data from European countries indicate an exceedance of the new tolerable intake The amount of a substance (e.g. nutrient or chemical) that is ingested by a person or animal via the diet. level across all age groups.

While these exceedances are a health concern, the toxicity The potential of a substance to cause harm to a living organism. of the most harmful dioxin-like PCB may have been overestimated due to use of internationally-agreed values known as ‘toxicity equivalency factors’ (TEFs). The CONTAM Panel would support a review of the TEFs for both dioxins and dioxin-like PCBs in light of new scientific data. If confirmed to be less toxic, this would reduce the concern for consumers.

• Dioxins and related PCBs: safe intake level reduced

EFSA's role

EFSA’s Panel on Contaminants in the Food Chain (CONTAM) provides scientific advice and risk assessments on dioxins and PCBs to EU risk managers to help them assess the need for regulatory measures such as the setting of maximum levels of dioxins and PCBs in contaminated food and feed. In particular, the CONTAM Panel is required to:

• Assess human and animal exposure using occurrence The fact or frequency of something (e.g. a disease or deficiency in a population) happening. data, in particular, from monitoring by EU Member States
• Consider the exposure for specific population groups, e.g. infants and children and/or people following specific diets
• Consider the exposure of farm and domestic animals and the level of carryover from feed to foods of animal origin
• Make recommendations for the collection of data on dioxins and PCBs that enable the refinement of risk assessments.

EFSA also collects and analyses occurrence data on dioxins and PCBs in food and feed. EU-wide data on the presence of dioxins and PCBs in the food chain can be used with food consumption data to evaluate the progress made in EU Member States in reducing the dietary exposure of the population to these contaminants. Risk managers may also use these data to revise maximum levels found in food and feed.

EU framework

n 2001, the European Union adopted a strategy on dioxins and PCBs aimed at reducing contamination levels of these substances in the environment, in feed and in foodstuffs to ensure a high level of public health protection. The European Commission website summarises the key milestones and provides details on the policy developments and regulatory measures taken since then.

• Food Contaminants - Dioxins and PCBs – European Commission

In 2001, the European Commission set for the first time maximum levels for dioxins, which were extended to dioxin-like PCBs in 2006. Regulation EU 1259/2011 and Regulation EU 277/2012 recently updated them and set maximum levels for non dioxin-like PCBs in food and feed respectively. These regulations took account of more recent data on dioxins and PCBs in food and feed published in two EFSA scientific monitoring reports, and an EFSA scientific opinion on non dioxin-like PCBs.

• Regulation EU 1259/2011 setting maximum levels of dioxins and PCBs in food – EUR-Lex
• Regulation EU 277/2012 setting maximum levels of dioxins and PCBs in feed – EUR-Lex

Member States are responsible for the monitoring of the levels of dioxins and PCBs in food. Previously, EFSA has been asked by the European Commission to collect, analyse and publish these data.

• Recommendation on monitoring of dioxins, dioxin-like PCBs and non-dioxin-like PCBs in foodstuffs – EUR-Lex