Nut allergy is on the increase, yet practical research has found a worrying lack of knowledge on the part of EHOs in dealing with the risks it presents. Ian Leitch, Ian Blair and David McDowell reveal their findings

Most research on the subject of peanut/nut allergy stresses the necessity of avoiding those foods that contain the trigger allergen. In practice, however, such total avoidance of peanuts/nuts is very difficult to achieve as the recent death of young athlete Ross Baillie, following consumption of nuts in a coronation chicken sandwich, shows.

Most peanut/nut allergy fatalities occur in the retail setting, where producers, retailers and EHOs may have insufficient knowledge of the actions and interventions necessary to protect sensitive consumers. The development of effective mechanisms to significantly reduce the consumption of trigger allergens by such individuals, without major disruption of normal food production and service systems, requires a wider recognition and greater understanding of the nature, frequency and consequences of clinically significant food allergy.

Food Allergy
The symptoms of food allergy (hypersensitivity) are induced as part of an abnormal immunological reaction to the food. While most food mediated allergic reactions are confined to the more trivial, such as gastric upset and hives, some people exhibit a range of much more severe reactions. These reactions include swelling of one of more parts of the body (including the tissue surrounding the windpipe), nausea and/or hypotension (low blood pressure). In the most severe cases, ingestion of trigger allergens can lead to rapid collapse, and death due to anaphylactic shock.

Although the symptoms of anaphylaxis can be reversed or suppressed by the rapid administration of intramuscular injections of adrenaline, its rapid onset, severity and unpredictable clinical sequelae mean that very rapid and appropriate medical intervention is essential. Unfortunately, timely and medically competent intervention cannot be guaranteed under all circumstances, so effective control strategies must be based on preventative public health measures rather than clinical remedition.

Nut allergy in the UK
A large-scale peanut allergy survey has been carried out in the UK.(7) Described by its authors as the first survey conducted to determine the prevalence of self-reported peanut allergy in a representative national population, the results showed that just under 0.5 per cent of the population (275,000 people) of the UK are allergic to peanuts with 0.1-0.2 per cent of the population (110,000) suffering severe anaphylactic shock symptoms such as breathing difficulties, wheezing, or loss of consciousness. These findings suggest that for a significant minority of the UK population, peanut allergy is a very real danger.

Allergy v poisoning
The reaction, or lack of reaction, to food allergy deaths is striking when compared with deaths from food poisoning. Following the deaths of 22 people in Scotland, as a direct result of E. coli O157:H7 food poisoning, an expert group was established, under the chairmanship of Professor Hugh Pennington, to examine the circumstances of the outbreak and advise on the implications for food safety.(9)

The report resulted in the implementation of a whole raft of new food inspection procedures. Compare this with the situation in relation to severe food allergic reactions. A study by Hide reported that around six people died from peanut allergy each year in the UK, a conclusion supported by a more recent report from the Chief Medical Officer.(6,8)

In spite of this continuing pattern, deaths due to peanut allergy (likely to have exceeded 60 within the last decade) do not seem to have triggered the same urgent government response as the smaller, but equally significant, number of deaths related to the above outbreak of food poisoning.

The Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment produced a report on peanut allergy in 1998, encouraging the labelling of food stuffs which contain peanuts, and advising those at risk of developing peanut allergy to avoid the consumption of peanuts.(5)

Managing Allergy
Most peanut/nut anaphylactic fatalities related to food allergy have occurred after the individual unknowingly ingested the allergen - at a restaurant, party, in take-away food etc. Sampson et al, reviewing six fatal cases of peanut induced anaphylaxis in children and adolescents, implicated peanuts (four patients), nuts (two patients), eggs (one patient) and milk (two patients), all of which were contained as ingredients in other foods.(16) None of the sufferers was aware that the trigger allergen was present in the food, illustrating that allergen avoidance strategies may be frustrated when the allergen is contained as a hidden food ingredient.

Such reports, and the significant fatality rates they record, demonstrate how vital it is for food allergy sufferers to know the full nature and composition any food they may eat, to be able to establish that trigger allergens are not present.

Law in Northern Ireland
The Food Labelling Regulations (NI) 1996 contain two major exemptions associated with allergy:
1. Exempting the labelling of ingredients if they are part of a compound ingredient in packaged foods and less than 25 per cent of the foodstuff. (If the biscuit base of a cheesecake contains nuts or peanuts as one of its compound ingredients, but this represents less than 25 per cent of the total product the ingredients of the compound ingredient do not need to be declared).
The UK government is seeking to have the labelling legislation amended to require the declaration of compound ingredients if they contain recognised allergens. At present food labelling legislation in the UK does not protect the allergic consumer.

2. Exempting open ready-for-sale foods from the requirement to label potentially allergenic ingredients, relying on the general requirement for hazard analysis outlined below to protect the consumer.
The Food Safety (General Food Hygiene) Regulations (NI) 1995 require business proprietors to apply hazard analysis principles to their business, to identify all steps in the business activities that are critical to food safety and to ensure adequate safety controls are introduced, maintained and reviewed.
Guidance to EHOs on the application of the risk assessment principles to food hygiene inspections, is given in the Lacots guidance note Food Hygiene Risk Assessment.(13) Although this document defines a hazard as anything with the potential to cause harm to the consumer, the note only gives examples of physical, chemical and microbiological hazards. Food allergens are not included on the list of hazardous substances to be considered by the inspecting officer.

Yet peanut/nut containing products do pose significant hazards to a small but significant proportion of consumers and peanuts/nuts should be more clearly recognised as a hazard, reviewed along with other hazards as part of normal inspection and risk assessment procedures, and subject to appropriate and effective control measures.

In practice
To establish the current position in relation to recognition of peanut allergy by EHOs, and to examine their response to such risks, a survey was undertaken, identifying 37 officers who carried out food hygiene inspections in a range of retail and service premises including bakeries, butcher shops, delicatessens, cafés, hotel dining rooms, restaurants, grocers, school canteens, and welfare catering establishments.
All of the officers surveyed were aware of the hazard analysis food safety technique, and all but one assessed its implementation by the food trade through discussions with food business proprietors and the provision of explanatory literature. (The one officer who did not assess the operation of the hazard analysis system in place indicated that this was due to a lack of training.)

Such uniformity of enforcement action may be recognised as the result of a food safety system, which includes standardised training of EHOs in relation to food safety enforcement duties, and the widespread dissemination of official written guidance to both the food trade and the enforcement officers.
In contrast with this almost universal knowledge and application of Haccp, there were considerable variations in the levels of knowledge and application of Haccp in relation to the control of food allergens. This may reflect the virtual absence of specific guidance in relation to the causes and effects of food allergy, within routine official guidance materials.

It is a matter of concern that just over half of the respondents (19/37) recognised peanuts as a major food allergen, and that only a slightly larger proportion of respondents (24/37) recognised nuts as major food allergens. Asphyxia (breathing difficulties), one of most serious symptoms of severe peanut/nut allergy was linked to the consumption of nuts in barely half (14/37) of the responses and to the consumption of peanuts in less than half (12/37) of the responses.

Association of asphyxia with other nut derivatives was considerably lower at 5/37 in the case of nut oil, and only 3/37 in relation to nut traces. It is also a matter of concern that none of the respondents recognised hypotension (severe lowering of blood pressure) as a potentially fatal symptom of food allergy.
The survey finding that only six EHOs (6/37) included the control of nuts/peanuts in their assessment of hazard analysis systems may reflect the current lack of attention given to this important area of food safety. Only one of the six officers had received hazard analysis training in the control of nuts/peanuts during their primary professional training.

Responses suggested that written guidance for EHOs and the food trade on the application of hazard analysis principles focus on physical, chemical and biological hazards, with virtually no advice on the control of food allergens.
Considering the importance and impacts of such industry advice in the enhancement of consumer safety, the current level of food allergy related information within available industry guidelines is inadequate.

Results
The study has revealed a clear lack of consistence in:
[a] the nature and extent of guidance to industry, and
[b] the extent to which food allergy related issues feature within hazard analysis inspections.

This may well be a consequence of the absence of co-ordinated formal pre and in-service training and advice on the control of food allergens. In the absence of widely available literature from the usual sources, those providing general information on the control of nuts/peanuts were using a limited amount of material, from non-government sources. None (0/6) of the officers carrying out a hazard analysis assessment of the control of nuts/peanuts provided the proprietors with any literature on control by the hazard analysis technique, perhaps because none was available, or perhaps because food allergy has not yet established a firm position as a matter of sufficient concern within professional practice and advice.

As noted previously, avoidance of trigger allergens and foods is the most widely recommended strategy for the prevention of serious allergic reactions. However, success in this regard is predicated on consistent and accurate identification and control of allergenic foods, and the prevention of cross-contamination throughout the food chain.

The accuracy and efficiency of criteria used by EHOs during the assessment of peanut/nut hazard analysis, as part of wider inspections, will dictate the levels of security achieved. Put more directly, if EHOs do not ask all the right questions, sensitive consumers will not be protected.
While a number of officers (6/37) did include peanut allergy aspects within their inspections, it is not clear that, even in these cases, these matters were dealt with in sufficient detail. The requirement to maintain clear identification of nut/peanut containing foods was not uniformly recognised.

Five officers (5/6) established whether or not peanuts/nuts were used in the premises. However, only two (2/6) established whether or not the proprietor asked for accurate written ingredients from all food suppliers, including being notified by the manufacturer if any change to ingredients of a food occurred, and only three (3/6) officers checked if the proprietor asked suppliers to ensure that all deliveries of nut/peanut containing products were clearly labelled as such.

Cross-contamination
Responses in relation to the mechanisms to limit cross-contamination during processing were also variable. Four EHOs (4/6) stated that they assessed whether or not foods containing nuts/peanuts were clearly identified by labelling at all stages while on the premises. Only half (3/6) assessed arrangements for the separation of peanuts/nuts from other foods during storage. Five (5/6) assessed whether or not nuts/peanuts were kept in closed, clearly labelled containers. Only one officer (1/6) assessing whether or not food premises used colour-coded equipment when preparing foods containing nuts/peanuts.

No respondents assessed cleaning schedules to determine if any special instructions were given to staff about the cleaning of equipment used to prepare foods containing nuts or peanuts. Considering the potential clinical sequelae of the transfer of even trace amounts of such food allergens into foods subsequently eaten by a sensitive consumer, the absence of rigour in the separation of, and prevention of cross-contamination between foods is a matter for concern.

The importance of staff actions in ensuring the safety of allergenic foods was largely unrecognised. Thus, only two EHOs (2/6) investigated the training of food preparation or serving staff in relation to food allergy.
There was limited and variable recognition of the need to assess measures by which peanut allergic customers could receive adequate information to enable them to exclude foods containing likely trigger allergens from their product selection.

Of the six EHOs assessing the control of nuts/peanuts by hazard analysis, two asked for clear menu identification, three asked for identification of foods on display and one checked if notices were displayed advising patrons to seek further information.

Overall, this is small proportion of the total group of respondents. Thus, it could be suggested that many consumers do not receive the guidance and information necessary to enable informed and secure selection of foods, and the consistent exclusion of trigger foods from their food intake.

Training needs
Individual respondents differed in terms of their accuracy in recognition of the factors, and the relative importance of these factors, which should be assessed within the food allergy component of an effective hazard analysis assessment. This suggests a need for co-ordinated, formal, pre and/or in-service training of EHOs in food allergen control. It also indicates the importance of incorporating food allergen control guidance into hazard analysis guidance documents [a] supplied to the environmental health profession and [b] circulated more widely within the food production, processing and service industries.

A number of officers (6/37) have already taken steps to apprise themselves of the challenges that trigger foods pose to sensitive consumers, and to include the control of peanut/nuts within their assessment of hazard analysis systems in use by the food trade. This group considered that they had enough knowledge to carry out this task effectively, but even half of them indicated that further relevant training would be useful.
Most of the respondents who did not include peanut/nuts hazards in their analysis (31/37), indicated that this was due to lack of knowledge (27/37) which is probably related to lack of training (26/27) in the area identified by 26 officers.

However, it is clear that, as reflective and committed professionals, the majority of respondents (29/37) considered that the control of nut/peanut food allergens is very important or important. It may now be time to put in place the necessary means which enable this recognition of an emerging challenge to the safety of a small but significant proportion of the population, to be effectively reflected by appropriate levels of knowledge and action by EHOs, taking the lead in the effective protection of the public's health.

Conclusion
This study has confirmed that EHOs within Northern Ireland, although committed to the application of Haccp principles in food control, do not in general use the Haccp system as a method of controlling food allergens in the retail sector.

Where such control is exercised by officers, considerable variations in the levels of knowledge and application of the system are evident, resulting in limited effectiveness and highlighting the need for effective training programmes to increase knowledge and hence operational effectiveness in this important area of food control.

Acknowledgements
The authors would like to thank the staff of the many environmental health departments in Northern Ireland in the completion of the questionnaires.

I Leitch is a senior EHO (food control) at Omagh District Council. I S Blair and D A McDowell work at the University of Ulster, Jordanstown. For further details contact Ian Leitch, tel. 028 82245321.

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