Sesame eliciting and safe doses in a large sesame allergic population.

BACKGROUND: Sesame is a significant food allergen causing severe and even fatal reactions. Given its increasing prevalence in western diet, sesame is listed as an allergenic food requiring labeling in the United States and EU. However, data on the population reaction doses to sesame are limited. METHODS: All sesame oral food challenges (OFCs), performed either for diagnosis or for threshold identification before the beginning of sesame oral immunotherapy (OIT) between November 2011 and July 2021 in Shamir medical center were analyzed for reaction threshold distribution. Safe-dose challenges with 90-120 min intervals were also analyzed. RESULTS: Two hundred and fifty patients underwent 338 positive OFCs, and additional 158 safe-dose OFCs were performed. The discrete and cumulative protein amounts estimated to elicit an objective reaction in 1% (ED01) of the entire cohort (n = 250) were 0.8 mg (range 0.3-6.3) and 0.7 mg (range 0.1-7.1), respectively, and those for 5% of the population (ED05) were 3.4 mg (range 1.2-20.6) and 4.5 mg (range 1.2-28.8), respectively. Safe-dose OFCs showed similar values of ED01 (0.8, 0.4-7.5 mg) and ED05 (3.4, 1.2-22.9 mg). While doses of ≤1 mg sesame protein elicited oral pruritus in 11.6% of the patients, no objective reaction was documented to this amount in any of the challenges, including safe-dose OFCs. CONCLUSIONS: This study provides data on sesame reaction threshold distribution in the largest population of allergic patients studied, with no right or left censored data, and with validation using a safe-dose OFC. It further supports the current methods for ED determination as appropriate for establishing safety precautions for the food industry.

The 50th percentile of the general population single eating occasion intake of food is optimal for the calculation of action levels for precautionary allergen labelling.

Lack of guidance regarding selection of food intake values for allergen risk assessment can lead to different outcomes for similar levels of allergens in food products. Several food consumption survey databases (United States, North-West Europe, and Netherlands) were analyzed to identify optimal food intake percentiles using a sensitivity analysis. Deterministic risk assessment scenarios using the 50th percentile up to the maximum intake per food group were compared with probabilistic risk assessment outcomes. The optimal intake percentile is the lowest percentile that results in a deterministic risk assessment outcome compliant with the predefined safety objective, i.e., the predefined risk of an objective allergic reaction at ED01, ED2.5, ED05 or ED10 doses of 14 allergenic foods. The P50 intake met these criteria in more than 99.9% of all 28,784 scenarios tested. The P50 is therefore recommended for deterministic allergen risk assessment and calculation of action levels for precautionary allergen labelling. In case a P50 value is not available, the mean is a good alternative, as analyses of the intake data showed that the mean generally is between the P50 and P65.

Updated full range of Eliciting Dose values for Cow's milk for use in food allergen risk assessment.

Access to Eliciting Doses (ED) for allergens enables advanced food allergen risk assessment. Previously, the full ED range for 14 allergenic foods, including milk, and recommendations for their use were provided (Houben et al., 2020). Additional food challenge studies with cow's milk-allergic patients added 247 data points to the original dataset. Using the Stacked Model Averaging statistical method for interval-censored data on the 697 individual NOAELs and LOAELs for milk generated an updated full ED distribution. The ED01 and ED05, the doses at which 1% and 5% of the milk-allergic population would be predicted to experience any objective allergic reaction, were 0.3 and 3.2 mg milk protein for the discrete and 0.4 mg and 4.3 mg milk protein for the cumulative dose distribution, respectively. These values are slightly higher but remain within the 95% confidence interval of previously published EDs. We recommend using the updated EDs for future characterization of risks of exposure of milk-allergic individuals to milk protein. This paper contributes to the discussion on the Reference Dose for milk in the recent Ad hoc Joint FAO/WHO Expert Consultation on Risk Assessment of Food Allergens. It will also benefit harmonization of food allergen risk assessment and risk management globally.

Reproducibility of food challenge to cow's milk: Systematic review with individual participant data meta-analysis.

BACKGROUND: Cow's milk (CM) is an increasingly common cause of severe allergic reactions, but there is uncertainty with respect to severity of reactions at low-level CM exposure, as well as the reproducibility of reaction thresholds. OBJECTIVE: We undertook an individual participant data (IPD) meta-analysis of studies reporting double-blind, placebo-controlled food challenges in CM to determine the rate of anaphylaxis to low-level exposures and the reproducibility of reaction thresholds. METHODS: We performed a systematic review and IPD meta-analysis of studies reporting relevant data. Authors were contacted to provide additional data and/or clarification as needed. Risk of bias was assessed using the National Institute for Clinical Excellence methodologic checklists. RESULTS: Thirty-four studies were included, representing data from over 1000 participants. The cumulative ED01 and ED05 (cumulative doses causing objective symptoms in 1% and 5% of the at-risk allergic population) were 0.3 (95% confidence interval [CI], 0.2-0.5) and 2.9 (95% CI, 1.6-5.4) mg, respectively. At meta-analysis, 4.8% (95% CI, 2.0-10.9) and 4.8% (95% CI, 0.7-27.1) of individuals reacting to ≤5 mg and ≤0.5 mg of CM protein had anaphylaxis (minimal heterogeneity, I2 = 0%). Then 110 individuals underwent repeat double-blind, placebo-controlled food challenges; the intraindividual variation in reaction threshold was limited to a ½-log change in 80% (95% CI, 65-89) of participants. Two individuals initially tolerated 5 mg CM protein but then reacted to this dose at a subsequent challenge, although neither had anaphylaxis. CONCLUSIONS: About 5% of CM-allergic individuals reacting to ED01 or ED05 exposure might have anaphylaxis to that dose. This equates to 5 and 24 anaphylaxis events per 10,000 patients exposed to an ED01 or ED05 dose, respectively, in the broader CM-allergic population. Most of these anaphylactic reactions would be mild and respond to a single dose of epinephrine.

Peanut Can Be Used as a Reference Allergen for Hazard Characterization in Food Allergen Risk Management: A Rapid Evidence Assessment and Meta-Analysis.

Regional and national legislation mandates the disclosure of "priority" allergens when present as an ingredient in foods, but this does not extend to the unintended presence of allergens due to shared production facilities. This has resulted in a proliferation of precautionary allergen ("may contain") labels (PAL) that are frequently ignored by food-allergic consumers. Attempts have been made to improve allergen risk management to better inform the use of PAL, but a lack of consensus has led to variety of regulatory approaches and nonuniformity in the use of PAL by food businesses. One potential solution would be to establish internationally agreed "reference doses," below which no PAL would be needed. However, if reference doses are to be used to inform the need for PAL, then it is essential to characterize the hazard associated with these low-level exposures. For peanut, there are now published data relating to over 3000 double-blind, placebo-controlled challenges in allergic individuals, but a similar level of evidence is lacking for other priority allergens. We present the results of a rapid evidence assessment and meta-analysis for the risk of anaphylaxis to a low-level allergen exposure for priority allergens. On the basis of this analysis, we propose that peanut can and should be considered an exemplar allergen for the hazard characterization at a low-level allergen exposure.

Poor understanding of allergen labelling by allergic and non-allergic consumers.

BACKGROUND: Understanding consumers' interpretation of allergy information is crucial for effective food safety policies. We evaluated consumer understanding of allergy information on foods in controlled, experimental studies. METHOD: Using 18 packaged foods, we evaluated consumer understanding of information about allergens in two experiments: First, a comparison of foods with no stated allergen versus allergen as a stated ingredient versus a precautionary allergen label (PAL); second, a comparison of three common variants of PAL. In each experiment, consumers with and without self-reported food allergy were asked to estimate the risk of allergic reaction and to rate the comprehensibility of the allergen information. In the second experiment, consumers were also asked which form of PAL they preferred. RESULTS: Risk of reaction was assessed as high and low for foods with the allergen stated as ingredient, or without any mention of allergen. However, risk assessment for PAL varied and was judged as higher by non-allergic than allergic participants (82% vs. 58%, p < .001). Understanding of risk associated with PAL also varied by health literacy (p < .001). Both allergic and non-allergic consumers judged all forms of allergy information to be unclear, especially products with no allergy information for non-allergic consumers. Products with a 'Produced in a Factory' PAL were perceived as less risky than 'May contain' or 'Traces of' PALs (p < .001), less than 40% of participants judged PAL information to be comprehensible, and participants preferred 'May contain' over the other PALs. CONCLUSION: Both allergic and non-allergic consumers find allergen information difficult to interpret on packaged foods and misunderstand PAL, incorrectly distinguishing different risk levels for different PAL wording. Clearer allergy information guidelines are called for, and the use of only one PAL wording is recommended.

Using data from food challenges to inform management of consumers with food allergy: A systematic review with individual participant data meta-analysis.

BACKGROUND: Eliciting doses (EDs) (eg, ED01 or ED05 values, which are the amounts of allergen expected to cause objective symptoms in 1% and 5% of the population with an allergy, respectively) are increasingly being used to inform allergen labeling and clinical management. These values are generated from food challenge, but the frequency of anaphylaxis in response to these low levels of allergen exposure and their reproducibility are unknown. OBJECTIVE: Our aim was to determine (1) the rate of anaphylaxis in response to low-level peanut exposure and (2) the reproducibility of reaction thresholds (and anaphylaxis) at food challenge. METHODS: We conducted a systematic review and individual participant data meta-analysis of studies that reported at least 50 individuals with peanut allergy reacting to peanut at double-blind, placebo-controlled food challenge (DBPCFC) and were published between January 2010 and September 2020. Risk of bias was assessed by using National Institute for Clinical Excellence methodologic checklists. RESULTS: A total of 19 studies were included (covering a total of 3151 participants, 534 of whom subsequently underwent further peanut challenge). At individual participant data meta-analysis, 4.5% (95% CI, 1.9% to 10.1%) of individuals reacted to 5 mg or less of peanut protein with anaphylaxis (moderate heterogeneity [I2 = 57%]). Intraindividual thresholds varied by up to 3 logs, although this variation was limited to a half-log change in 71.2% (95% CI, 56.2% to 82.6%) of individuals. In all, 2.4% (95% CI, 1.1% to 5.0%) of patients initially tolerated 5 mg of peanut protein but then reacted to this dose at subsequent challenge (low heterogeneity [I2 = 16%]); none developed anaphylaxis. CONCLUSION: Around 5% of individuals reacting to an ED01 or ED05 level of exposure to peanut might develop anaphylaxis in response to that dose. This equates to 1 and 6 anaphylaxis events per 2500 patients exposed to an ED01 or ED05 dose, respectively, in the broader population of individuals with peanut allergy.

Allergen labelling: Current practice and improvement from a communication perspective.

BACKGROUND: Allergen information on product labels is crucial in food allergy management, though inadequacy in current labelling practices is one of the major causes for accidental reactions upon consuming prepacked food products. OBJECTIVE: This study analyses current status of communicating allergen information on food labels and provides practical recommendations for improving the label format based on communication theory. METHODS: Product labels (N 288) of seven food categories from private label products and brands were obtained at three retailers in the Netherlands. Information regarding the 14 EU-regulated allergens was evaluated by the frequency of emphasizing allergens in the ingredient list, use of precautionary allergen labelling (PAL), icons and an allergen information section. Effectiveness of communication was assessed evaluating readability and findability of information on allergens using principles of Gestalt and Cognitive Load theories. RESULTS: As requested by EU regulation 1169/2011, emphasizing allergens in the ingredient list was almost 100%, all other presentations of information on allergens on labels was highly diverse. A separate allergen information section was present on most private label products. This section could, but not necessarily did, repeat allergens from the ingredient list and/or give a PAL. Brands often provided a PAL at the end of the ingredient list. Part of the products displayed an icon at different locations of the label. Label background, a lack of cohesion and variation in location of topics hamper the identification of relevant information on allergens by (allergic) consumers. Recommendations include a standardized order for mandatory and voluntary topics on the label and a separate allergen information section. CONCLUSION AND CLINICAL RELEVANCE: Overall, consumers encounter a wide and inconsistent range in ways of presentation of allergen information on labels. Standardization according to basic design principles can improve usability and support safe food purchases for allergic consumers.

A systematic comparison of food intake data of the United States and the Netherlands for food allergen risk assessment.

National population-based food consumption surveys are used in food allergen risk assessment. It would be beneficial if food intake data is interchangeable between countries to bridge potential gaps present in national survey data, which is only possible when risk assessment outcomes for comparable food product groups between countries are fairly similar. Additionally, merged food intake data would enable risk assessments that cover scenarios for various countries, if based on the most critical situation. Therefore, we systematically compared risk assessment outcomes for a broad range of food groups based on United States and Dutch population food consumption survey data. We calculated risks for 14 allergenic foods for 9 concentrations (1-10,000 ppm) to assess comparability. Depending on the assumed allergen concentration, risk assessment outcomes for 20% (10 out of 49) food groups differed considerably. We consider the number of potentially relevant risk differences too high to conclude that food intake data from the US and The Netherlands can be used interchangeably. To allow risk assessments that cover scenarios for several countries, we recommend development and use of a food intake dataset based on the highest intake levels for each food group of the involved countries to facilitate risk management efforts and harmonization.

Full range of population Eliciting Dose values for 14 priority allergenic foods and recommendations for use in risk characterization.

Previously, we published selected Eliciting Dose (ED) values (i.e. ED01 and ED05 values) for 14 allergenic foods, predicted to elicit objective allergic symptoms in 1% and 5%, respectively, of the allergic population (Remington et al., 2020). These ED01 and ED05 values were specifically presented and discussed in the context of establishing Reference Doses for allergen management and the calculation of Action Levels for Precautionary Allergen Labeling (PAL). In the current paper, we publish the full range of ED values for these allergenic foods and provide recommendations for their use, specifically in the context of characterizing risks of concentrations of (unintended) allergenic proteins in food products. The data provided in this publication give risk assessors access to full population ED distribution information for 14 priority allergenic foods, based on the largest threshold database worldwide. The ED distributions were established using broad international consensus regarding suitable datapoints and methods for establishing individual patient's NOAELs and LOAELs and state of the art statistical modelling. Access to these ED data enables risk assessors to use this information for state-of-the-art food allergen risk assessment. This paper contributes to a harmonization of food allergen risk assessment and risk management and PAL practices.

Allergen risk assessment: Food intake levels of the general population represent those of food allergic patients.

Unintentional intake of allergens through food products poses a daily risk for allergic patients. Models estimating the risk of reactions mostly use intake data from general population surveys. Our study evaluates the comparability of food intake levels in the general population to those in the food allergic population. Data were collected by a 24-h recall method on 2 non-consecutive days in 38 cow's milk and/or hen's egg and 35 peanut and/or tree nut allergic adult patients. All products were assigned to food groups previously developed for allergen risk assessment. Food intake distributions from the allergic populations and a matched sample from the Dutch National Food Consumption Survey were compared, and risk assessments were performed. Food intake data was obtained for 92% of the food groups. Comparison of the intake showed no statistically significant differences between either of the two allergic populations and the general population. Consequently, only small variations in estimated risks were found, that would not result in different risk management decisions. In conclusion, food intake data from the general population can be used for food allergen risk assessment and will not lead to a relevant under- or overestimation of the risk for the food allergic population.

Risk of shared equipment in restaurants for consumers with peanut allergy: a simulation for preparing Asian foods: A simulation for preparing Asian foods.

BACKGROUND: Allergic reactions to meals consumed outside the home are common and can be severe and sometimes fatal. OBJECTIVE: To quantify the risk reduction potentially achieved by increasing an individual's threshold sensitivity to peanut (such as by means of immunotherapy) in scenarios of peanut exposure through shared kitchen materials in a restaurant setting. METHODS: Three versions of popular peanut-containing sauces were selected to represent common ingredients used in Asian cooking. Different combinations of utensils, equipment, sauces, and test conditions were prepared by a professional chef, with or without common cleaning procedures, to represent normal daily practice. Residue amounts of peanut-containing material on kitchen equipment and utensils were measured and used for quantitative risk assessment to model the risk reduction associated with increasing an individual's threshold. RESULTS: Shared utensils had mean residue amounts of 23 to 1519 mg peanut protein (no cleaning) and 3 to 82 mg peanut protein (after water rinse). Shared woks and pans had up to 20 mg peanut protein after rinsing. Individuals who reach a threshold of 300 mg peanut protein have a predicted relative risk reduction of 94.9% to greater than 99.99% with brief cleaning. With no cleaning, relative risk reductions were 63.5% to 91.1% for individuals with a baseline threshold of less than or equal to 100 mg peanut protein who reach a threshold of 300 mg peanut protein, increasing to 91% to 99.7% when reaching a threshold value of 1000 mg peanut protein. CONCLUSION: In all shared kitchen material scenarios that we studied, achieving an eliciting dose of 300 or 1000 mg peanut protein seems clinically relevant for the peanut-allergic population.

Updated population minimal eliciting dose distributions for use in risk assessment of 14 priority food allergens.

Food allergy and allergen management are important global public health issues. In 2011, the first iteration of our allergen threshold database (ATDB) was established based on individual NOAELs and LOAELs from oral food challenge in roughly 1750 allergic individuals. Population minimal eliciting dose (EDp) distributions based on this dataset were published for 11 allergenic foods in 2014. Systematic data collection has continued (2011-2018) and the dataset now contains over 3400 data points. The current study provides new and updated EDp values for 14 allergenic foods and incorporates a newly developed Stacked Model Averaging statistical method for interval-censored data. ED01 and ED05 values, the doses at which 1%, and respectively 5%, of the respective allergic population would be predicted to experience any objective allergic reaction were determined. The 14 allergenic foods were cashew, celery, egg, fish, hazelnut, lupine, milk, mustard, peanut, sesame, shrimp (for crustacean shellfish), soy, walnut, and wheat. Updated ED01 estimates ranged between 0.03 mg for walnut protein and 26.2 mg for shrimp protein. ED05 estimates ranged between 0.4 mg for mustard protein and 280 mg for shrimp protein. The ED01 and ED05 values presented here are valuable in the risk assessment and subsequent risk management of allergenic foods.

Deriving individual threshold doses from clinical food challenge data for population risk assessment of food allergens.

BACKGROUND: Food allergies are a significant public health issue, and the only effective management option currently available is strict avoidance of all foods containing the allergen. In view of the practical impossibility of limiting risks to zero, quantitative allergen risk assessment and management strategies are needed. OBJECTIVE: We sought to develop appropriate methods for informing population-based risk assessments and risk management programs to benefit all stakeholders but particularly patients with food allergy. METHODS: Individual thresholds for food allergens (maximum tolerable doses and minimum eliciting doses) can ideally be established through double-blind, placebo-controlled food challenges. If double-blind, placebo-controlled food challenge data are not available, data from widely used open food challenges using predefined objective criteria can also provide useful data regarding minimum eliciting doses. For more than 20 years, the Netherlands Organisation for Applied Scientific Research and the Food Allergy Research and Resource Program at the University of Nebraska-Lincoln have been collecting individual maximum tolerable doses and minimum eliciting doses that produce objective symptoms from published and unpublished clinical data to better refine knowledge regarding the sensitivity of the population to food allergens. RESULTS: In this article we provide in-depth insights into the methodology applied by the Netherlands Organisation for Applied Scientific Research and Food Allergy Research and Resource Program to derive individual maximum tolerable doses and minimum eliciting doses for objective symptoms from clinical food challenge data. More than 90 examples for determining individual allergic thresholds are presented. CONCLUSION: With the methodology presented in this article, we aim to stimulate harmonization and transparency in quantitative food allergen risk assessment and risk management programs, encouraging their wider adoption.

Evidence-based approaches to the application of precautionary allergen labelling: Report from two iFAAM workshops.

Food allergy is a major public health concern with avoidance of the trigger food(s) being central to management by the patient. Food information legislation mandates the declaration of allergenic ingredients; however, the labelling of the unintentional presence of allergens is less defined. Precautionary allergen labelling (PAL) was introduced by the food industry to help manage and communicate the risk of reaction from the unintended presence of allergens in foods. In its current form, PAL is counterproductive for consumers with food allergies as there is no standardized approach to applying PAL. Foods with a PAL often do not contain the identified food allergen while some products without a PAL contain quantities of common food allergens that are capable of inducing an allergic reaction. Integrated Approaches to Food Allergen and Allergy Risk Management (iFAAM) was an EU-funded project that aimed to improve the management of food allergens by the food industry for the benefit of people with food allergies. Within iFAAM, a clinically validated tiered risk assessment approach for food allergens was developed. Two cross-stakeholder iFAAM workshops were held on 13-14 December 2016 and 19-20 April 2018. One of the objectives of these workshops was to develop a proposal to make PAL effective for consumers. This paper describes the outcomes from these workshops. This provides the basis for the development of more informative and transparent labelling that will ultimately improve management and well-being in consumers with food allergy.

Sensitivity analysis to derive a food consumption point estimate for deterministic food allergy risk assessment.

One of the input parameters in food allergy risk assessment is the amount of a given food consumed at an eating occasion. There is no consensus on how to use food consumption data when assessing the risk from unintended allergen presence in food products. A sensitivity analysis was performed to establish the optimal food consumption estimate for a deterministic food allergy risk assessment. Exposure was calculated for consumption percentiles (50th percentile, P50 to maximum) using the iFAAM consumption database in conjunction with an allergen concentration range from 1 to 1000 ppm. The resulting allergen intakes were compared to the allergic population reference doses proposed by Taylor et al. (2014) for 10 major allergenic foods. Optimal consumption percentiles were defined as those which predicted an intake below the relevant reference dose and met the defined acceptable risk level confirmed by probabilistic risk assessments. Analysis showed that, for 99% of the food groups, the P50 consumption met our criteria, while the P75 did so for 100% of the food groups. We suggest that the P75 is the optimal point estimate for use in deterministic food allergy risk assessment. It meets the safety objective and is adequately conservative for a public health context.