Hypersensitivity reactions to food additives

Metabolic, toxicological, chemical, and commercial perspectives on esterification of dietary polyphenols: a review

Molecular modifications have been practiced for more than a century and nowadays they are widely applied in food, pharmaceutical, or other industries to manipulate the physicochemical, bioactivity, metabolic/catabolic, and pharmacokinetic properties. Among various structural modifications, the esterification/O-acylation has been well-established in altering lipophilicity and bioactivity of parent bioactive compounds, especially natural polyphenolics, while maintaining their high biocompatibility. Meanwhile, various classic chemical and enzymatic protocols and other recently emerged cell factory technology are being employed as viable esterification strategies. In this contribution, the main motivations of phenolic esterification, including the tendency to replace synthetic alkyl phenolics with safer alternatives in the food industry to improve the bioavailability of phenolics as dietary supplements/pharmaceuticals, are discussed. In addition, the toxicity, metabolism, and commercial application of synthetic and natural phenolics are briefly introduced. Under these contexts, the mechanisms and reaction features of several most prevalent chemical and enzymatic esterification pathways are demonstrated. In addition, insights into the studies of esterification modification of natural phenolic compounds and specific pros/cons of various reaction systems with regard to their practical application are provided.

Sulfur content in foods and beverages and its role in human and animal metabolism: A scoping review of recent studies

Sulfur is a vital element that all living things require, being a component of proteins and other bio-organic substances. The various kinds and varieties of microbes in nature allow for the transformation of this element. It also should be emphasized that volatile sulfur compounds are typically present in food in trace amounts. Life cannot exist without sulfur, yet it also poses a potential health risk. The colon's sulfur metabolism, which is managed by eukaryotic cells, is much better understood than the S metabolism in gastrointestinal bacteria. Numerous additional microbial processes are anticipated to have an impact on the content and availability of sulfated compounds, as well as intestinal S metabolism. Hydrogen sulfide is the sulfur derivative that has attracted the most attention in relation to colonic health, but it is still unclear whether it is beneficial or harmful. Several lines of evidence suggest that sulfate-reducing bacteria or exogenous hydrogen sulfide may be the root cause of intestinal ailments, including inflammatory bowel diseases and colon cancer. Taurine serves a variety of biological and physiological purposes, including roles in inflammation and protection, additionally, low levels of taurine can be found in bodily fluids, and taurine is the primary sulfur component present in muscle tissue (serum and urine). The aim of this scoping review was to compile data from the most pertinent scientific works about S compounds' existence in food and their metabolic processes. The importance of S compounds in various food products and how these compounds can impact metabolic processes are both stressed in this paper.

The protective effect of butylated hydroxytoluene and 3-hydroxytyrosol on food allergy in mice

OBJECTIVE

To test the effect of two dietary antioxidants: butylated hydroxytoluene (BHT) and 3-hydroxytyrosol (3-HT) in experimental food allergy.

METHODS

BALB/c mice maintained on control diet or diet with BHT or 3-HT were sensitized with ovalbumin (OVA) or saline through transdermal exposure. Plasma OVA-specific IgE (OVA-IgE) and IgG1 (OVA-IgG1) antibody levels were determined using ELISA. Sensitized mice were challenged by oral gavage with OVA. Rectal temperature (RT) was measured before and after challenge. Mast cell degranulation was quantified by measuring the plasma levels of mouse mucosal mast cell protease-1 (mMCP-1). Flow cytometry was carried out to evaluate the percentage Th2 cells from the spleen.

RESULTS

Mice on either a 3-HT or BHT diet showed a significantly decreased IgE response to OVA sensitization and less severe anaphylaxis, as evidenced by a diminished drop in body temperature, attenuated clinical signs, a more rapid recovery and decreased mast cell degranulation (as determined by lower plasma mMCP-1 levels).

CONCLUSION

The present study indicates two dietary antioxidants: BHT and 3-HT may be protective against experimental food allergy. These results suggest 3-HT and BHT could potentially be useful for prevention of food allergy.

WinMLR program for the determination of sorbic and benzoic acids in food samples

The program WinMLR has been developed to quantify sorbic and benzoic acids in soft drinks, fruit juices, and soy sauce by making a multilinear regression treatment of experimental data to a linear combination of standard signals. The spectra of sorbic and benzoic acid and samples were obtained from a conventional spectrophotometer, which has been saved in an ASCII file to be applied with the WinMLR program. Before to determine sorbic and benzoic acids in samples, the wavelength validation and calibration parameters were studied. Standard solutions of sorbic and benzoic acids were used for the calibration parameters to measure the individual analyte. If the sample has simultaneously both compounds, it is better to choose the synthetic mixture for the calibration parameters. This technique provides a good recovery in the range of 80.4-104.8% without a complicated and expensive instrument.

Adverse reactions to food additives

Food additives are naturally occurring or synthetic substances that are added to food to modify the color, taste, texture, stability, or other characteristics of foods. These additives are ubiquitous in the food that we consume on a daily basis and, therefore, have been the subject of much scrutiny about possible reactions. Despite these concerns, the overall prevalence of food additive reactions is 1-2%, with a minority of the wide variety of symptoms attributed to food-additive exposure being reproduced by double-blind placebo controlled challenges. Reactions can be broadly classified into either immunoglobulin E (IgE)- and non-IgE-mediated reactions, with natural additives accounting for most IgE-mediated reactions, and both natural and synthetic additives being implicated in the non-IgE-mediated reactions. Reactions that include asthma exacerbations, urticaria and/or angioedema, or anaphylaxis with ingestion of a food additive are most deserving of further allergy evaluation. In this article, we discussed the different types of adverse reactions that have been described to various food additives. We also reviewed the specifics of how to evaluate and diagnose a food additive allergy in a clinic setting.

Simultaneous and rapid analysis of chemical preservatives in processed animal products by ultra-performance liquid chromatography

An ultra-performance liquid chromatography-tunable ultraviolet method was optimized and validated for the simultaneous analysis of nine chemical preservatives in processed animal products. The limits of detection and quantification for the preservatives were within the ranges of 0.02-0.23 and 0.07-0.76 μg/mL, respectively. The relative standard deviations for intraday analyses of retention time and peak area were 0.00-0.23 and 0.03-2.93%, respectively, whereas, those for interday analyses were 0.67-2.30 and 2.12-5.37%, respectively. Of the nine preservatives spiked into six different animal products, dehydroacetic acid spiked into soft cheese exhibited the lowest recovery rate of 72.1 ± 0.36% at the lowest concentration (0.25 g/kg). Comparing data between UPLC and high-performance liquid chromatography with a 5% significance level, the t-statistic was 1.42. Moreover, sorbic acid was detected in 16 animal products (0.11-2.49 g/kg) when 278 products were analyzed for preservatives.

Evaluation of Natural Food Preservatives in Domestic and Imported Cheese

In milk and milk products, a number of organic acids naturally occur. We investigated the contents of some naturally occurred food preservatives (sorbic acid, benzoic acid, propionic acid, nitrite, and nitrate) contained in domestic and imported cheeses to establish the standard for the allowable range of food preservatives content in cheese. 8 kinds of domestic precheeses (n=104), 16 kinds of domestic cured cheeses (n=204) and 40 kinds of imported cheeses (n=74) were collected. Each domestic cheese was aged for a suitable number of months and stored for 2 mon at 5℃ and 10℃. No preservatives were detected in domestic soft and fresh cheeses, except cream cheese. In case of semi-hard cheeses, 2-5 mg/kg of benzoic acid was detected after 1-2 mon of aging. In imported cheeses, only benzoic acid and propionic acid were detected. The average benzoic acid and propionic acid contents in semi-hard cheese were 8.73 mg/kg and 18.78 mg/kg, respectively. Specifically, 1.16 mg/kg and 6.80 mg/kg of benzoic acid and propionic acid, respectively, were contained in soft cheese, 3.27 mg/kg and 2.84 mg/kg, respectively, in fresh cheese, 1.87 mg/kg and not detected, respectively, in hard cheese, and 2.07 mg/kg and 182.26 mg/kg, respectively, in blended processed cheese.

Fortification of yogurts with different antioxidant preservatives: A comparative study between natural and synthetic additives

Consumers demand more and more so-called "natural" products and, therefore, the aim of this work was to compare the effects of natural versus synthetic antioxidant preservatives in yogurts. Matricaria recutita L. (chamomile) and Foeniculum vulgare Mill. (fennel) decoctions were tested as natural additives, while potassium sorbate (E202) was used as a synthetic additive. The fortification of yogurts with natural and synthetic antioxidants did not cause significant changes in the yoghurt pH and nutritional value, in comparison with control samples (yogurt without any additive). However, the fortified yogurts showed higher antioxidant activity, mainly the yogurts with natural additives (and among these, the ones with chamomile decoction). Overall, it can be concluded that plant decoctions can be used to develop novel yogurts, by replacing synthetic preservatives and improving the antioxidant properties of the final product, without changing the nutritional profile.

Allergic and immunologic reactions to food additives

For centuries, food additives have been used for flavouring, colouring and extension of the useful shelf life of food, as well as the promotion of food safety. During the last 20 years, the studies implicating the additives contained in foods and medicine as a causative factor of allergic reactions have been proliferated considerably. In this review, we aimed to overview all of the food additives which were approved to consume in EU and find out how common and serious allergic reactions come into existence following the consuming of food additives.

Antimicrobial activities of active component isolated from Lawsonia inermis leaves and structure-activity relationships of its analogues against food-borne bacteria

The antimicrobial activities of Lawsonia inermis leaf extract and 2-hydroxy-1,4-naphthoquinone analogues against food-borne bacteria. The antimicrobial activities of five fractions derived from the methanol extract of Lawsonia inermis leaves were evaluated against 7 food-borne bacteria. 2-Hydroxy-1,4-naphthoquinone was isolated by chromatographic analyses. 2-Hydroxy-1,4-naphthoquinone showed the strong activities against Bacillus cereus, Listeria monocytogenes, Salmonella enterica, Shigella sonnei, Staphylococcus epidermidis, and S. intermedius, but exerted no growth-inhibitory activities against S. typhimurium. The antimicrobial activities of the 2-hydroxy-1,4-naphthoquinone analogues were tested against 7 food-borne bacteria to establish structure-activity relationships. Hydroxyl (2-hydroxy-1,4-naphthoquinone and 5-hydroxy-1,4-naphthoquinone), methoxy (2-methoxy-1,4-naphthoquinone), and methyl (2-methyl-1,4-naphthoquinone, and 5-hydroxy-2-methyl-1,4-naphthoquinone) functional groups on the 1,4-naphthoquinone skeleton possessed potent activities, whereas bromo (2-bromo-1,4-naphthoquinone and 2,3-dibromo-1,4-naphthoquione) and chloro (2,3-dichloro-1,4-naphthoquinone) exhibited no activity against 7 food-borne bacteria. The L. inermis leaf extract and 2-hydroxy-1,4-naphthoquinone analogues should be useful as natural antimicrobial agents against food-borne bacteria.

Screening and identification of the antibacterial bioactive compounds from Lonicera japonica Thunb. leaves

Our aim was to screen for antibacterial bioactive compounds from Lonicera japonica leaves. Staphylococcus aureus and Escherichia coli were used as the indicator bacteria. Bacteriostatic assay-guided extraction and stepwise partitioning of the samples yielded five compounds of interest. Antimicrobial activities of the compounds were determined using a disk diffusion assay. Extracts, fractions, and compounds from L. japonica leaves possessed considerable antibacterial activities against the tested bacterial strains and the most active fraction was attributed to J3B2, which primarily contained 3,5-di-O-caffeoylquinic acid and 4,5-di-O-caffeoylquinic acid. Meanwhile, five bacteriostatic constituents were isolated (3-O-caffeoylquinic acid, secoxyloganin, luteoloside, 3,5-di-O-caffeoylquinic acid and 4,5-di-O-caffeoylquinic acid), among which, secoxyloganin was isolated for the first time from leaves. The antibacterial activity of the compounds was in the order of 3,5-bis-O-caffeoyl quinic acid, 4,5-bis-O-caffeoylquinic acid, luteoloside>3-O-caffeoylquinic acid>secoxyloganin. Our results suggested that the phenolic compounds might significantly contribute to antibacterial activity and were the most responsible for the bacteriostatic activity of L. japonica leaves.

Review article: cinnamon- and benzoate-free diet as a primary treatment for orofacial granulomatosis

BACKGROUND

Orofacial granulomatosis is a rare chronic granulomatous inflammatory disease of the lips, face and mouth. The aetiology remains unclear but may involve an allergic component. Improvements have been reported with cinnamon- and benzoate-free diets.

AIMS

To explore the prevalence of compound and food sensitivity and examine the dietary treatments used in orofacial granulomatosis.

METHODS

A comprehensive literature search was carried out and relevant studies from January 1933 to January 2010 were identified using the electronic database search engines; AGRIS 1991-2008, AMED 1985-2008, British Nursing and Index archive 1985-2008, EMBASE 1980-2008, evidence based medicine review databases (e.g. Cochrane DSR), International Pharmaceutical and Medline 1950-2008.

RESULTS

Common sensitivities identified, predominantly through patch testing, were to benzoic acid (36%) food additives (33%), perfumes and flavourings (28%), cinnamaldehyde (27%), cinnamon (17%), benzoates (17%) and chocolate (11%). The cinnamon- and benzoate-free diet has been shown to provide benefit in 54-78% of patients with 23% requiring no adjunctive therapies. A negative or positive patch test result to cinnamaldehyde, and benzoates did not predict dietary outcome. The most concentrated source of benzoate exposure is from food preservatives. Use of liquid enteral formulas can offer a further dietary therapy, particularly in children with orofacial granulomatosis.

CONCLUSION

Management of orofacial granulomatosis is challenging but cinnamon- and benzoate-free diets appear to have a definite role to play.

Food Allergy in Dogs and Cats: A Review

Food allergy (FA) is defined as "all immune-mediated reactions following food intake," in contrast with food intolerance (FI), which is non-immune-mediated. Impairment of the mucosal barrier and loss of oral tolerance are risk factors for the development of FA. Type I, III, and IV hypersensitivity reactions are the most likely immunologic mechanisms. Food allergens are (glyco-)proteins with a molecular weight from 10-70 kDa and are resistant to treatment with heat, acid, and proteases. The exact prevalence of FA in dogs and cats remains unknown. There is no breed, sex or age predilection, although some breeds are commonly affected. Before the onset of clinical signs, the animals have been fed the offending food components for at least two years, although some animals are less than a year old. FA is a non-seasonal disease with skin and/or gastrointestinal disorders. Pruritus is the main complaint and is mostly corticoid-resistant. In 20-30% of the cases, dogs and cats have concurrent allergic diseases (atopy/flea-allergic dermatitis). A reliable diagnosis can only be made with dietary elimination-challenge trials. Provocation testing is necessary for the identification of the causative food component(s). Therapy of FA consists of avoiding the offending food component(s).

A retrospective analysis of case series using home-prepared and chicken hydrolysate diets in the diagnosis of adverse food reactions in 181 pruritic dogs

The purpose of this retrospective study was to compare home-prepared and chicken hydrolysate diets in the diagnosis of canine adverse food reactions (AFR). Seventy-two dogs were fed home-prepared diets and 109 were fed hydrolysate. Owners chose the type of diet at presentation, and ingredients of home-prepared diets were selected depending on each dog's dietary history. Ectoparasitic infestations and microbial infections were treated during the trials. Cutaneous and gastrointestinal signs and pruritus scores were recorded before starting the diet, 6 weeks into the trials and after provocation with the original diets. AFR was diagnosed if pruritus resolved during the trial and recurred on dietary provocation. The dropout rate was lower for home-prepared diets although not statistically significant (18.1% home prepared; 24.7% hydrolysate, P=0.377). AFR alone was diagnosed in 10 dogs (17%) using home-prepared diets and in 15 (18.3%) fed the hydrolysate. Gastrointestinal problems were more frequent in dogs with AFR than in dogs without AFR (P=0.001). Another 11 dogs (18.6%) in the home-prepared diet group and 20 (24.4%) in the hydrolysate diet group had AFR concurrent with other pruritic diseases, mainly atopy. The similar frequencies of AFR diagnosis in the two groups (P=0.837 AFR; P=0.416 concurrent AFR) indicate that the chicken hydrolysate diet may be a valuable alternative to home-prepared diets in the diagnosis of canine AFR. Prospective cross-over studies are warranted to confirm these findings.

Estimates of the mean per capita daily intake of benzoic and sorbic acids in Brazil

The daily intakes of benzoates and sorbates from selected food categories were estimated in Brazil in 1999. The Budget method was used as a first screening procedure for the estimation of the safety aspects of the maximum permitted levels of benzoates and sorbates established by the Brazilian food legislation. This screening indicated that benzoates should be further investigated. In a second step, the daily intakes of these preservatives were assessed by combining measured levels of these additives with national food consumption data derived from a household economic survey and a packaged good market survey. Benzoate and sorbate levels in soft drinks, fruit juices, margarine, yoghurt and cheese were determined by HPLC with a photodiode array detector (detection at 228 nm for benzoic acid, 260 nm for sorbic acid). The estimated intakes of benzoates and sorbates for the average consumer were below the ADIs, ranging from 0.3 to 0.9 and 0.2 to 0.3 mg kg(-1) body weight, respectively. Soft drinks were identified as the main source of benzoates representing >80% of the estimated intake.

Final report on the safety assessment of Benzyl Alcohol, Benzoic Acid, and Sodium Benzoate

Benzyl Alcohol is an aromatic alcohol used in a wide variety of cosmetic formulations as a fragrance component, preservative, solvent, and viscosity-decreasing agent. Benzoic Acid is an aromatic acid used in a wide variety of cosmetics as a pH adjuster and preservative. Sodium Benzoate is the sodium salt of Benzoic Acid used as a preservative, also in a wide range of cosmetic product types. Benzyl Alcohol is metabolized to Benzoic Acid, which reacts with glycine and excreted as hippuric acid in the human body. Acceptable daily intakes were established by the World Health Organization at 5 mg/kg for Benzyl Alcohol, Benzoic Acid, and Sodium Benzoate. Benzoic Acid and Sodium Benzoate are generally recognized as safe in foods according to the U.S. Food and Drug Administration. No adverse effects of Benzyl Alcohol were seen in chronic exposure animal studies using rats and mice. Effects of Benzoic Acid and Sodium Benzoate in chronic exposure animal studies were limited to reduced feed intake and reduced growth. Some differences between control and Benzyl Alcohol-treated populations were noted in one reproductive toxicity study using mice, but these were limited to lower maternal body weights and decreased mean litter weights. Another study also noted that fetal weight was decreased compared to controls, but a third study showed no differences between control and Benzyl Alcohol-treated groups. Benzoic Acid was associated with an increased number of resorptions and malformations in hamsters, but there were no reproductive or developmental toxicty findings in studies using mice and rats exposed to Sodium Benzoate, and, likewise, Benzoic Acid was negative in two rat studies. Genotoxicity tests for these ingredients were mostly negative, but there were some assays that were positive. Carcinogenicity studies, however, were negative. Clinical data indicated that these ingredients can produce nonimmunologic contact urticaria and nonimmunologic immediate contact reactions, characterized by the appearance of wheals, erythema, and pruritus. In one study, 5% Benzyl Alcohol elicited a reaction, and in another study, 2% Benzoic Acid did likewise. Benzyl Alcohol, however, was not a sensitizer at 10%, nor was Benzoic Acid a sensitizer at 2%. Recognizing that the nonimmunologic reactions are strictly cutaneous, likely involving a cholinergic mechanism, it was concluded that these ingredients could be used safely at concentrations up to 5%, but that manufacturers should consider the nonimmunologic phenomena when using these ingredients in cosmetic formulations designed for infants and children. Additionally, Benzyl Alcohol was considered safe up to 10% for use in hair dyes. The limited body exposure, the duration of use, and the frequency of use were considered in concluding that the nonimmunologic reactions would not be a concern. Because of the wide variety of product types in which these ingredients may be used, it is likely that inhalation may be a route of exposure. The available safety tests are not considered sufficient to support the safety of these ingredients in formulations where inhalation is a route of exposure. Inhalation toxicity data are needed to complete the safety assessment of these ingredients where inhalation can occur.

Severe food-induced vasculitis in two children

Food-induced vasculitis seems to be rare and is considered by some as controversial. The reported cases in the literature are few and mostly on adult patients. Described in this report are two children with severe vasculitis caused by specific foods. They were diagnosed at two separate allergy centers that have a special interest in food allergies. Case 1 was an 8-year-old girl with a 9-month history of cutaneous vasculitis with large joints involvement. Case 2 was a 23-month-old girl with an 8-month history of multiple hospitalizations for recurrent acute severe cutaneous and mucous membrane vasculitis with large joints involvement. In both patients, skin biopsy showed leucocytoclastic vasculitis. In neither of the patients could the symptoms be attributed to drug intake, infection, autoimmunity, or other systemic disease. Case 1 had a moderately elevated serum total immunoglobulin E (IgE) level and strongly positive skin test and radioallergosorbent test (RAST) to cow's milk and hen's egg, both of which were proven to be the cause by elimination-challenge tests. Case 2 had a slightly elevated serum total IgE level, but negative skin tests to foods, including chocolate that was suspected by the mother. Avoidance of chocolate resulted in remission, except following accidental ingestion of cocoa-containing products. These findings support the few previous reports on food-induced vasculitis, an entity that seems rare but may be more common than currently realized.

Threshold of toxicological concern for chemical substances present in the diet: a practical tool for assessing the need for toxicity testing

The de minimis concept acknowledges a human exposure threshold value for chemicals below which there is no significant risk to human health. It is the underlying principle for the US Food and Drug Administration (FDA) regulation on substances used in food-contact articles. Further to this, the principle of Threshold of Toxicological Concern (TTC) has been developed and is now used by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) in their evaluations. Establishing an accepted TTC would benefit consumers, industry and regulators, since it would preclude extensive toxicity evaluations when human intakes are below such threshold, and direct considerable time and cost resources towards testing substances with the highest potential risk to human health. It was questioned, however, whether specific endpoints that may potentially give rise to low-dose effects would be covered by such threshold. In this review, the possibility of defining a TTC for chemical substances present in the diet was examined for general toxicity endpoints (including carcinogenicity), as well as for specific endpoints, namely neurotoxicity and developmental neurotoxicity, immunotoxicity and developmental toxicity. For each of these endpoints, a database of specific no-observed-effect levels (NOELs) was compiled by screening oral toxicity studies. The substances recorded in each specific database were selected on the basis of their demonstrated adverse effects. For the neurotoxicity and developmental neurotoxicity databases, it was intended to cover all classes of compounds reported to have either a demonstrated neurotoxic or developmentally neurotoxic effect, or at least, on a biochemical or pharmacological basis were considered to have a potential for displaying such effects. For the immunotoxicity endpoint, it was ensured that only immunotoxicants were included in the database by selecting most of the substances from the Luster et al. database, provided that they satisfied the criteria for immunotoxicity defined by Luster. For the developmental toxicity database, substances were selected from the Munro et al. database that contained the lowest NOELs retrieved from the literature for more than 600 compounds. After screening these, substances showing any effect which could point to developmental toxicity as broadly defined by the US were recorded in the database. Additionally, endocrine toxicity and allergenicity were addressed as two separate cases, using different approaches and methodology. The distributions of NOELs for the neurotoxicity, developmental neurotoxicity and developmental toxicity endpoints were compared with the distribution of NOELs for non-specific carcinogenic endpoints. As the immunotoxicity database was too limited to draw such a distribution of immune NOELs, the immunotoxicity endpoint was evaluated by comparing immune NOELs (or LOELs-lowest-observed-effect levels-when NOELs were not available) with non-immune NOELs (or LOELs), in order to compare the sensitivity of this endpoint with non-specific endpoints. A different methodology was adopted for the evaluation of the endocrine toxicity endpoint since data currently available do not permit the establishment of a clear causal link between endocrine active chemicals and adverse effects in humans. Therefore, this endpoint was analysed by estimating the human exposure to oestrogenic environmental chemicals and evaluating their potential impact on human health, based on their contribution to the overall exposure, and their estrogenic potency relative to endogenous hormones. The allergenicity endpoint was not analysed as such. It was addressed in a separate section because this issue is not relevant to the overall population but rather to subsets of susceptible individuals, and allergic risks are usually controlled by other means (i.e. labelling) than the Threshold of Toxicological Concern approach. (ABSTRACT TRUNCATED)

Gastrointestinal allergy

Many problems have been attributed to allergic reactions arising by way of the gastrointestinal tract. The term "food allergy" must be used with greater care. Allergy is but one of many adverse reactions to foods, several of which respond to dietary manipulation. Although gastrointestinal allergy is known to occur in animals, there is a need for greater precision in the use of terminology, further clarification of the problems, and challenge to confirm the diagnosis.

Adverse reactions to food additives in children with atopic symptoms

In a multicenter study conducted at four Danish hospital pediatric departments, the parents of 472 consecutive children were informed of this project to determine the incidence of intolerance of food additives among children referred to an allergy clinic with symptoms of asthma, atopic dermatitis, rhinitis, or urticaria. After a 2-week period on an additive-free diet, the children were challenged with the eliminated additives. The food additives investigated were coloring agents, preservatives, citric acid, and flavoring agents. Carbonated "lemonade" containing the dissolved additives was used for the open challenge. Two doses were used: a low dose and a 10-fold higher dose. Gelatin capsules were used for a double-blind challenge. The children were 4-15 years old, and they were attending an outpatient pediatric clinic for the first time. Of the 379 patients who entered the study, 44 were excluded and 335 were subjected to open challenge. A total of 23 children developed positive reactions after the open challenge. Sixteen of these patients accepted the double-blind challenge, and six showed a positive reaction to preservatives (atopic dermatitis, asthma, rhinitis), coloring agents (atopic dermatitis, asthma, urticaria, gastrointestinal symptoms), and citric acid (atopic dermatitis, gastrointestinal symptoms). The incidence of intolerance of food additives was 2% (6/335), as based on the double-blind challenge, and 7% (23/335), as based on the open challenge with lemonade. Children with atopic skin symptoms had a statistically increased risk of a positive reaction. This may have consequences for the future clinical investigation of children with atopic cutaneous symptoms.