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Other Allergens and Triggers

In addition to food triggers, other substances or factors can trigger reactions or contribute to them. These include sulphites, physical exercise, latex, pollen, and oral allergy syndrome.

On this page:Sulphites >
     Differentiating food allergy from chemical sensitivity >
     Identifying sulphites >
     Synonyms for sulphites >
     Likely sources of sulphites >
     Possible sources of sulphites >
Physical activity and allergic reactions >
     Foods commonly associated with exercise-induced anaphylaxis >
     Additional triggers >
Pollen, dust, mould, animals >
Oral Allergy Syndrome (pollen-fruit syndrome) >
     Foods associated with birch pollen allergy >
      Symptoms of Oral Allergy Syndrome >
     Oral allergy syndrome and healthy eating >
Latex >
     Sources of latex >
     Latex and cross reactions >
     Latex and catering >


Sulphites are inorganic salts used as preservatives and to preserve the colour of food. Although they are harmless to most people, for others they can cause allergy-like symptoms. These include symptoms such as hives, coughs, dizziness, gastrointestinal disorders, and respiratory problems, as well as anaphylactic reactions and asthma attacks.

Differentiating between food allergy and chemical sensitivity

Sulphite reactions are defined as chemical sensitivities rather than allergic reactions. The majority of reported cases occurred in asthmatic adults, particularly women and patients using corticosteroid pumps. For this at risk population, sulphites are thought to trigger or aggravate asthma.

Unlike food allergies, chemical sensitivities do not cause IgE antibody production. While food proteins are the cause of allergic reactions to food, scientists have not yet determined the cause of chemical sensitivities. Certain chemicals may cause autoimmune diseases in at risk populations or be associated with immune system deficiencies explaining the onset of symptoms.

Despite the fact that the first reported case of chemical sensitivity occurred close to 70 years ago, it remains a condition that is poorly defined and difficult to explain. Immunological, neurological, metabolic, sociocultural, and even psychological hypotheses have been proposed to explain the onset of chemical sensitivity. To date, there is no conclusive evidence to support any of these hypotheses.

How to identify sulphites

The use of sulphites in consumer products is regulated by the same Labelling Act as food priority allergens and gluten. Sulphites must always be clearly declared on food labels using its common name, whether present as an ingredient or as a component of an ingredient. It will be found in the list of ingredients or under the notice: “contains.”

Synonyms for sulphites

Sulphurous acid, sulfurous anhydride, sulphiting agents, bisulphite/dithionite/metabisulphite/sodium sulphite, bisulphite/potassium metabisulphite, sulphur dioxide, sodium dithionite, E220, E221, E222, E223, E224, E225, E226, E227, E228 (European names).

Sources of sulphites

Ale, beer, soft drinks, cider, condiments (sauerkraut, pickles, ketchup, mustard, relish, horseradish, pickled onions, etc.), jam, candied/crystallized fruit (e. g. apples, grapes, maraschino cherries), canned or frozen fruits/vegetables (e. g. mushrooms, olives, peas, peppers, tomatoes), dried fruits/vegetables (e. g. apples, apricots, coconuts, tomatoes, papayas, peaches, pears, pineapples, grapes), fruit toppings, gelatin, jellies, commercial guacamole, snacks (e.g. fruit bars, candies, corn chips, trail mix, chocolate bars,…), lemon and lime juice/ concentrate, fruit/vegetable (e.g., grapes, white grapes), coconut juice, marmalade, molasses, fried/frozen/dehydrated/pureed/peeled/precut mixed starchy foods (e.g., corn, potatoes, sugar beets, noodles, rice), mincemeats, muesli, tomato paste/pulp/purée, pectin, fresh grapes, sauces, cabbage salad, commercial fruit salad, fruit syrups, sugar syrups (e.g. glucose syrups, glucose solids, dextrose syrups), soups/blends, tea, wine (alcoholic/non-alcoholic), vinegar, wine vinegar, vinaigrettes.

Possible sources of sulphites

Processed foods, seasonings, cereals, deli meats, crackers, shellfish and molluscs (e. g. shrimp), spices (e. g. curry), corn starch or semolina, dried herbs, glucose, hot dogs, lettuce, fish, soy products, bakery products (e. g. bread, cookies, cakes, waffles), sausages, among others.

Physical activity

Exercise-induced anaphylaxis is triggered by physical effort, and is characterized by a sensation of heat and itching, redness, and generalized urticaria (red and white swollen patches) with tingling. If the triggering activity is not stopped, the symptoms can worsen and include blocked airways and cardio-vascular failure. Environmental factors can contribute to the onset of exercise-induced anaphylaxis. Often, the reaction will occur during exercise within minutes or hours of eating foods that are normally harmless. It can be associated with a specific food or not. Even a person who does not have a food allergy can be affected by this type of reaction.

Foods commonly associated with exercise-induced anaphylaxis

The foods most commonly associated with exercise-induced anaphylaxis are celery, wheat, seafood, and hazelnuts. For some, if consumption of such foods is not followed by physical activity, there will generally be no reaction.

Additional triggers

Environmental factors can contribute to the onset of some reactions. These include hot conditions, exposure to pollens, and the use of drugs such as aspirin and anti-inflammatory drugs. As for physical activity, aerobic activities requiring cardiovascular effort are more those more likely to trigger an allergic reaction (e. g. jogging, tennis, hockey, racquetball, dancing, etc.).

Pollen, dust, mold, and animals

Allergic reactions to pollens and other aeroallergens are common. For more medical information and practical advice regarding these allergies, please contact the Quebec Lung Association. If you have been diagnosed with, or suspect a pollen-food allergy, please refer to the section below for additional information.

Oral allergy syndrome (pollen-food syndrome)

Having seasonal allergies does not necessarily lead to food allergies. However, it does increase the risk for them. Oral allergy syndrome affects many people who have an allergy to pollen (including birch pollen, but also ragweed, grass pollen turf, ragweed (more common in North America) and wormwood (more common in Europe). These reactions can occur at any time of the year but are often most severe during the pollen season. The reaction usually occurs immediately after eating raw fruits or vegetables, but can happen with cooked foods, as well (especially nuts). This reaction is due to the similarity between the proteins found in fruits and vegetables and those found in the triggering pollen (the immune system confuses them). This is called a pollen-fruit cross-reactivity pollen-fruit yon, where a reaction occurs to both the pollen and the foods containing similar proteins. Sometimes during the pollination season, the allergic person can develop a hypersensitivity to these foods.

Foods associated with birch pollen allergy

People with allergies to birch pollen may react to certain fruits, vegetables, and nuts. Common triggers include kiwis, apples, pears and stone fruits such as apricots, cherries, peaches, nectarines, and plums. Vegetables associated with birch pollen include, those in the potato family (pepper, tomato, etc.) and the parsley family (carrot, celery, fennel, parsnip, dill, etc.). These foods are more likely to cause abnormal allergic reaction in people allergic to birch pollen. Filberts, hazelnuts, and walnuts are also responsible for oral allergy syndrome.

Birch allergy is the most common cause of oral allergy syndrome. It is estimated that between 50% and 70% of people allergic to birch pollen will develop a cross allergy to at least one food such as apple, peach, pear, or celery. The proteins involved in this allergy have a similar structure to Bet v 1, the allergen causing the initial sensitization to birch pollen. Allergic rhinitis usually precludes the onset of oral allergy syndrome. This table shows the most common pollen-food associations encountered with respect to oral allergy syndrome.

Symptoms of oral allergy syndrome

The main symptoms of oral allergy syndrome are itching and burning of the lips, mouth, and throat and in some cases, gastrointestinal discomfort. Although serious reactions are rare, it is best to avoid fresh foods that trigger these reactions.

Oral allergy syndrome and healthy eating

In cases where extensive dietary restrictions are warranted, it may be difficult to maintain a balanced and varied diet. If this is the case, it may be helpful to enlist the support of a qualified nutrition professional. L’Ordre professionnel des diététistes du Québec has a registry of dietitians available for consultation. Look for recipes inspirations in our article Allergy and pollen (in French).

To continue reading about this, see this French article:
Connaissez-vous le syndrome de l’allergie orale?


Natural latex is derived from the “rubber tree”, whose sap contains potentially allergenic proteins.

Where is latex found?

Latex is used in the manufacturing of condoms, rubber gloves, inflatable balloons, medical equipment, surgical gloves, teats from baby bottles, toys, tires, elastic bands, etc.

Are there cross allergic reactions associated to latex?

Latex allergy increases the risk for allergy to banana, avocado, kiwi, apricot, chestnuts, grapes, passion fruit and pineapple, as these foods have proteins similar to those found in the rubber tree’s sap. It is reported that in 35% of cases, such food-proteins could cause allergic reactions in people allergic to latex.

Latex gloves and catering

Allergy Quebec discourages the use of natural latex materials, such as latex gloves, when handling food in catering. These materials can leave allergenic latex proteins in prepared foods and trigger allergic reactions of varying severity in people who are sensitive to them.

The use of latex gloves in the workplace may also increase the incidence of sensitization in employees, leading to latex allergy. Alternatives to latex such as vinyl, nitrile, or neoprene are encouraged by Allergies Quebec as safe synthetic options when the use of gloves is necessary.

MAPAQ, Votre carnet d’information, Les allergies alimentaires, 2014, p.6.
Barnig, C. et De Blay, F. (2013). Physiopathologie du syndrome d’hypersensibilité chimique multiple. Revue des Maladies Respiratoires, 30:446-450.
Barnig, C. et De Blay, F. (2013). Physiopathologie du syndrome d’hypersensibilité chimique multiple. Revue des Maladies Respiratoires, 30:446-450.
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Sussman G., Sussman A. et Sussman D. Le syndrome de l’allergie orale. JAMC, mars-avril 2011.
Yagami T. Allergies to cross-reactive plan proteins. Int Arch Allergy Immunol, 2002, 128:271-79.