Chemicals in food: safety controls

Safety rules and procedures for working with food additives, pesticides, contact materials and processes such as high temperature cooking and irradiation

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Food businesses are responsible for ensuring their food is safe, and that it complies with legislation on food additives and rules on reducing or eliminating human health risks caused by contaminants.

Chemical contaminants can come from:

  • farming - eg pesticides, veterinary medicines
  • packaging and other contact materials
  • processing - eg acrylamides
  • storage - eg naturally-occurring aflatoxins
  • the environment - eg pollutants such as dioxins

Food additives must comply with specified legislation which aims to ensure that they are only used when there is a technological justification, that they do not mislead consumers, and do not have effects on consumer health.

Natural components of plants may also be toxic - such as glycoalkaloids in potatoes - while some may be harmful if not cooked properly - for example lectins in pulses. There are also some foodstuffs that can cause allergies in some people - such as peanuts.

This guide provides food businesses with information on safety rules and procedures with regard to food additives, pesticides, contact materials and processes such as high temperature cooking and irradiation.

Food additives

Food additives are intentionally added to food for a technological purpose during its manufacture and processing.

Additives may be:

  • antioxidants - used in food prepared with fats or oils to protect them against deterioration caused by rancidity
  • colours - used to make food look more attractive or to replace colours which have been lost during processing
  • emulsifiers, stabilisers, gelling agents and thickeners - used to help mix ingredients together that would usually separate, eg oils and water
  • flavour enhancers - used to bring out the flavour of food without adding a flavour of their own
  • preservatives - used to keep food safe for longer
  • sweeteners - used to replace sugar in certain foods, eg energy reduced products

All additives used in food must be on the EU approved list. Most additives are restricted to certain foods at maximum specified levels. EU legislation states that most additives used in foods must be labelled clearly in the list of ingredients, either by name or by an E number. If an additive has an E number, it means it has passed EU safety tests.

You must ensure that any additives you use in your food have been approved for use, and that you comply with relevant legislation about the levels of additives and the foods in which they are used.

Under the Food Labelling Regulations 1996 you must also ensure that any food you supply to caterers or consumers is clearly labelled with a list of the ingredients used, including any additives.

How to reduce acrylamide in food processing

Acrylamide is a natural by-product that forms when carbohydrate-rich foods such as potatoes and cereals - bread, biscuits and other bakery products - are fried, baked, or roasted at temperatures above 120°C.

It is not found in food that has not been heated, or that has been cooked using methods such as boiling or microwaving.

Since these foods have been cooked at high temperatures for hundreds of years, it is likely that acrylamide has been present in our food for many generations. It is thought to form from two chemicals that occur naturally in the food - an amino acid called asparagine and certain types of sugar.

Acrylamide is also found in:

  • tobacco
  • coffee
  • raw, dried or pickled food - such as olives, prunes and dried pears

Acrylamide has been found to cause nerve damage in people who have been accidentally exposed to it whilst at work (it is used as an industrial chemical in strengthening paper and in the clarification of water). It is also considered to be a carcinogen.

There are currently no regulatory limits set for acrylamide in food. However, there is a limit for the amount of acrylamide allowed to migrate from food contact plastic into food. The specific migration limit in force means that acrylamide migrating into food from food contact plastic should not be detectable at a limit of 0.01 milligrams per kilogram of food.

The formation of acrylamide is a product of the Maillard reaction - the browning of food when cooking caused by a reaction of natural sugars. Current advice for reducing acrylamide includes:

  • choosing specific varieties of raw materials - such as potatoes with a lower level of sugars
  • adding asparaginase - an enzyme which reduces the production of acrylamide
  • lowering the cooking temperature and reducing cooking time to reduce browning

The Confederation of the Food and Drink Industries of the EU (Confederation des industries Agro-Alimentaires de l’UE or CIAA) has produced guidance in the form of a ‘toolbox’ and sector specific pamphlets on how to reduce acrylamide in the processing of different types of foods - such as biscuits, bread, potato crisps and French fries.

The pamphlets are food sector-specific and have recently been updated. They are now available in 22 European languages.

You can find the pamphlets on the Europa website.

The Acrylamide Infonet was set up following a 2002 consultation by the World Health Organization (WHO) and the Food and Agriculture Organization of the UN. It provides a single source of information on existing and ongoing research into the effects of acrylamide in food and links to external resources.

Other contaminants in food derived from food processing

Process contaminants have the potential to increase the risk of cancer, so levels in food have to be kept as low as is reasonably practical.

The FSA is currently conducting a survey of four ‘process contaminants’ in food - ie contaminants formed during the processing of food - to gain a clearer picture of the levels of these contaminants in food normally consumed in the UK. The survey is a three-year rolling programme which started in 2007 and covers:

  • acrylamide
  • 3-MCPD (3-monochloropropanediol)
  • 3-MCPD esters
  • furan
  • ethyl carbamate

The survey report is published annually. The 2007 report was published in September and the 2008 report was published in July. You can find results of the 2008 process contaminant survey on the FSA website.

The use of pesticides

The use of pesticides in agriculture, horticulture, forestry and domestic gardening is regulated by the Chemical Regulation Directorate (CRD) - part of the Health and Safety Executive (HSE).

The CRD:

  • regulate pesticides in accordance with national and European requirements
  • actively monitor the marketing and use of pesticides and take enforcement action where necessary
  • provide operational policy advice to government ministers

The CRD aims to ensure that pesticides are safe for people and the environment. They do this by regulation, encouraging best practice and researching into alternative pest control methods. The FSA works closely with CRD to make sure that consumer safety is given priority in pesticide regulation and surveillance.

Use of pesticides in the UK must be approved by government ministers and monitored through official programmes.

Pesticide residue levels

Rigorous safety assessments are undertaken to make sure that any pesticide residues remaining in food are not harmful to people. Residues are controlled through a system of statutory Maximum Residue Levels (MRLs).

The MRL is the maximum amount of residue likely to remain in food products when a pesticide has been used correctly. It is expressed as milligrams of residue per kilogram of food product. Before being approved for use, a pesticide must be proven to be completely safe for human consumption at its MRL - and may be safe at much higher levels.

All current EU MRLs are listed in Annex II of EC Regulation 396/2005.

In the UK, the independent Pesticide Residues Committee oversees the surveillance programme for residues in both home produced and imported food.

The purpose of this monitoring is to check that:

  • no unexpected residues occur in crops
  • human dietary intakes of residues in foods are within acceptable levels
  • pesticide residues do not exceed the statutory MRL

The use of veterinary medicines

The use of veterinary medicines in the UK is controlled and monitored by the Veterinary Medicine Directorate (VMD). The VMD is an executive agency of the Department for Environment, Food and Rural Affairs in the UK.

A high priority in the VMD’s work is ensuring that veterinary medicines are used in a way that protects food safety and the environment. Their remit includes:

  • regulating veterinary medicines in accordance with national and European guidelines
  • putting in place and operating monitoring programmes for residues in food to ensure consumers are not exposed to unacceptable residues of veterinary medicines
  • providing policy advice to government ministers
  • actively monitoring the marketing and use of veterinary medicines and taking appropriate enforcement action

The VMD fulfils its remit by making scientific assessments of the safety and effectiveness of potential medicines before they are authorised, and operating systems of post-authorisation surveillance and monitoring. They work closely with the FSA to make sure that consumer safety is given priority in veterinary medicines authorisation and surveillance.

Veterinary medicines residue levels

Rigorous safety assessments are undertaken to make sure that any veterinary medicines residues remaining in food are not harmful to people. For food that might contain residue of a particular medicine, an agreed Maximum Residue Level (MRL), is calculated.

The MRL is the maximum concentration of residue that is legally permitted or acceptable in or on a food. Any residues below the MRL pose no concerns for consumer health. Even when the MRL is exceeded, it is unlikely that the residues are of concern - however, an individual assessment would be made.

The VMD organises investigations on farms where residues above the MRL originated. They determine the cause and give advice to farmers.

In the UK, the independent Veterinary Residues Committee oversees the VMD’s monitoring of residues in both home-produced and imported food. The purpose of this monitoring is to check that:

  • the system of authorising veterinary medicines is working correctly and, when used as directed, any residues of veterinary medicines present in foods do not exceed the statutory MRLs
  • residues of banned or unauthorised veterinary medicines are not present in foodstuffs

Regulations on food colours

Food colouring additives are used by manufacturers to change or enhance the natural colours of food. They are often used:

  • to mask natural colour variations
  • to replace colour lost in storage or processing
  • to make the food appear more appetising
  • for effect - eg in cake decoration

Colouring additives are used in both commercial and domestic food preparation. They can be either natural or synthetic (artificial).

The Colours in Foods Regulations 1995 define which food colour additives may be used in the UK. They list the permitted colours, set down conditions for their use and specify which colours may not be sold directly to the public.

Certain colours are banned in food production. You can download guidance notes on the Colours in Foods Regulations from the FSA website (PDF, 171K).

Food colours and Attention Deficit Hyperactivity Disorder (ADHD)

In 2008, following research that suggested a link between certain food colours and ADHD in children, UK ministers and the FSA recommended that, although they remain permitted additives under EU legislation, UK manufacturers should remove six colour additives from their food by the end of 2009.

You should check whether your suppliers still use these colours, including those supplying you from abroad. The six colours are:

  • sunset yellow FCF (E110)
  • quinoline yellow (E104)
  • carmoisine (E122)
  • allura red (E129)
  • tartrazine (E102)
  • ponceau 4R (E124)

From 20 July 2010, most food and drink containing any of these six colours supplied to the EU market must carry additional warning information.

You can download European Parliament and Council Regulation 1333/2008 on food colourings from the Europa website (PDF, 150K).

Many consumers now prefer to buy products with fewer artificial additives - especially in children’s foods - so you may want to consider reducing your general use of colourings.

Sudan dyes and industrial dyes not permitted in food

Certain industrial red dyes - such as Para Red and the four Sudan dyes (Sudan I, Sudan II, Sudan III and Sudan IV, otherwise know as scarlet red) - are not permitted for use in food, as they are carcinogenic. Sudan dyes are used legally in shoe and floor polish, solvents, oils, waxes and petrol.

Sudan dyes have been used illegally in spices, sauces, chutneys, vinegars and palm oil, among many other products and, in some of these cases, food products have been recalled.

The FSA provides food alerts about illegal dyes added to food to enforcement authorities who follow up with businesses that might be affected.

Other illegal dyes are:

  • butter yellow
  • metanil yellow
  • orange G
  • rhodamine B
  • orange II
  • toluidine red

Since 2003, all imports of dried, crushed and ground spices, curry powders, circumin and palm oil have had to be accompanied by test certificates showing that they do not contain Sudan dyes. Any consignment without relevant documentation is detained for sampling and analysis.

Random sampling must also be carried out by port and local authorities - the FSA sample over 1,000 consignments every year. Any consignment found to contain Sudan is destroyed.

From January 2010, the current rules on imported foods containing Sudan dyes will be repealed and replaced by a new system of controls and testing applicable to all imported food.

You can find a list of Sudan dye-affected foods on the FSA website.

Food contact materials and packaging

Food contact materials are those that are intended to, or can be reasonably expected to, come into contact with food. This can be packaging, cookware, cutlery, tableware, work surfaces or food processing machinery and equipment. Manufacturers of food packaging materials and producers and sellers of food must ensure that any food contact materials do not present a health risk for consumers.

European Regulation (EC) 1935/2004 on materials and articles intended to come into contact with food came into force on 3 December 2004. It sets out general safety requirements for materials and articles that come into contact with food - including those might come into contact with foods or transfer their constituents to food, for example printing inks and adhesive labels.

It also ensures that these materials do not change the nature, substance or quality of the food.

It includes descriptions of ‘active’ and ‘intelligent’ food packaging materials:

  • active materials - release a substance into the foodstuff to extend its shelflife, or maintain or improve its condition
  • intelligent materials - monitor the condition of the food or its surrounding environment inside packaging and communicate this to the consumer - eg a label which changes colour if it detects bacteria or gases, meaning that the food is not fresh

You can download guidance on Regulation 1935/2004 and its impact on UK legislation from the FSA website (PDF, 444K).

Future European guidelines are likely to cover:

  • plastics - including packaging made from recycled plastics
  • rubber
  • paper and board
  • glass
  • metals and alloys
  • wood and cork
  • textiles
  • waxes

The FSA is responsible for monitoring the safety of food contact materials in the UK, while the Food Contact Materials Unit carries out scientific research into detecting chemicals that have transferred to the food.

Documenting food packaging materials

Food packaging materials - including those imported from outside the EU - should always have compliance documentation.

All food packaging businesses - apart from the primary materials producers - are required by law to establish and document good practices and procedures.

For more information about compliance and best practice in food packaging documentation, you can download guidance on food packaging from the FSA website (PDF, 204K).

Understanding irradiated foods

Food irradiation is the processing of food by ionising radiation. The Food Irradiation (England) Regulations 2009 allow for four methods of irradiation:

  • gamma rays from the radionuclide cobolt-60
  • gamma rays from the radionuclide caesium-137
  • x-rays generated from machine sources operated at or below an energy level of 5MeV (megaelectron volt)
  • electrons generated from machine sources operated at or below an energy level of 10MeV

Irradiation is used to:

  • destroy harmful bacteria - such as e-coli , salmonella, campylobacter
  • delay fruit ripening
  • stop potatoes and other vegetables from sprouting
  • reduce spoilage of food to prolong shelf life
  • rid food of organisms harmful to plants - such as fruit flies

The Food Irradiation (England) Regulations 2009 allow the irradiation of seven categories of foods:

  • fruit
  • vegetables
  • cereals
  • bulbs and tubers
  • dried aromatic herbs, spices and vegetable seasonings
  • fish and shellfish
  • poultry

Thorough research has been carried out on food irradiation, and it has been found to be a safe and effective treatment method by the WHO, the UN Food and Agriculture Organisation and the European Community Scientific Committee for Food.

The FSA recognises irradiation as a safe processing technique and undertakes safety inspections of the food irradiation facilities in the UK, of which there is currently only one.

By law, all food that has been irradiated must be labelled as ‘irradiated’ or ‘treated with ionising radiation’. The FSA can detect whether foods have been irradiated, and local authority enforcement officer regularly take samples food from the market place to ensure that products are correctly labelled.

Further information

FSA Helpline

020 7276 8829

FSA Helpline (for artificial sweeteners, enzymes, and flavourings)

020 7276 8581

FSA Helpline (for other additives)

020 7276 8570

Chemicals Regulation Directorate Helpline

01904 455 775

Veterinary Medicines Directorate Enquiry Line

01932 336 911

Chemicals and food safety information on the FSA website

Download food labelling law advice from the FSA website (PDF, 101K)

Acrylamide FAQs on the FSA website

Food sector-specific acrylamide pamphlets on the Europa website

2008 process contaminant survey results on the FSA website

UK pesticide legislation information on the HSE website

Pesticide FAQs on the FSA website

Veterinary medicine use legislation guidance on the VMD website

Veterinary medicines authorised for use in the UK on the VMD website

Veterinary medicine use FAQs on the FSA website

Reducing nicarbazin residues in UK chickens from the FSA website

Download Colours in Foods Regulations guidance notes from the FSA website (PDF, 171K)

Download European Parliament and Council Regulation 1333/2008 from the Europa website (PDF, 150K)

Foods affected by Sudan dye listed on the FSA website

Para Red FAQs on the FSA website

Download UK food contact materials legislation advice from the FSA website (PDF, 444K)

Download food packaging best practice guidance from the FSA website (PDF, 204K)

Published 8 October 2012