Fish, Crustaceans and Molluscs
Fish, crustaceans, and shellfish are listed as priority allergens in Canada. Collectively, these can be identified as ‘seafood’. This page focuses on facts specific to seafood allergy, available resources, and special considerations related to these allergens.
|On this page:||Statistics and facts on seafood allergy >|
|Seafood reference guide >|
| Terms that may indicate the presence of seafood|
| Foods that are likely and possible sources of seafood|
| Possible sources of seafood in everyday products|
| Substituting fish, crustaceans, and molluscs in your diet|
|Helpful resources >|
Facts about fish, crustaceans and molluscs allergy
- This food group is associated with a relatively high prevalence of food allergies.
- Fish allergy affects 0.9% of children under 18 years of age and 0.5% of adults in Canada. Crustaceans and shellfish allergy is estimated to affect 0.8% of children under 18 years of age and 1.6% of adults.
- Crustacean and mollusc allergies predominantly affect adults and are less common among children.
- Allergy to fish, crustaceans, and shellfish generally persists throughout life.
- The term seafood refers to crustaceans and molluscs. Crustaceans have a rigid shell, while molluscs have a two-part shell. Lobster, shrimp, and crab are classified as crustaceans; while scallops, mussels and oysters as molluscs.
- A person might be allergic to one or more species of fish, crustaceans and/or molluscs.
- The risk of contamination between fish, crustaceans and molluscs is very high, especially in fish markets and grocery stores. If you are allergic to fish or seafood, it is better to avoid these points of sale and choose packaged products.
- Imitation seafood (e. g. simulated crab) may contain fish and should be avoided.
- Allergenic proteins from fish and seafood can be found in cooking fumes (e.g., steam from lobster cooking water, fish cooking in a pan). The simple inhalation of allergenic proteins can cause allergic reactions to people with highly sensitive allergies, even without consumption of the allergen .
- Allergy or food poisoning? Signs and symptoms of an allergic reaction to fish are sometimes confused with scombroidosis, a food poisoning to histamine. The symptoms of scombroidosis (burning sensation in the throat, facial swelling, itching, rashes, and abdominal pain) are similar to those of anaphylaxis . Scombroidosis cases are most often associated with the consumption of tuna, bonito, and mackerel due to the high amount of histamine found in their flesh when not fresh. It is the decomposition of the fish that allows for the formation of histamine. However, this decomposition is difficult to detect, because it often occurs before a foul-smelling odour is released from the fish.
Fish, crustaceans and molluscs – REFERENCE GUIDE
|Fish broth and sauce||Golden||Grondin|
|Nuoc Mam||Orange roughy||Perch|
|Sea bream||Sea toad||Shad|
|Tarama (mullet-based recipe)||Tassergal||Tilapia|
|Whiting||Yellow Perch||Yellowtail flounder|
|Shrimps and prawns||Spiny lobster||Tomalli|
|Squid||St James Shell|
|Health Canada’s food allergen labelling regulations established in 2012 prohibit use of the following terms. Manufacturers must declare the presence of fish, crustaceans and shellfish in the list of ingredients either on the label of their product or in the words “Contains”. However, it is important to keep those terms in mind when travelling, as regulations vary from one country to another. In some cases, it may also be useful to know them when we are offered artisanal or homemade products.|
|Cocktail made from Clamato tomatoes (clams)|
|Soups||Kamaboko (crustaceans)||Vin (fish)||Chowder|
|Entrance and appetizers||Pot au feu||Yogurt with omega-3 (fish)||Juice with omega-3 (fish)|
|Cocktail with spicy tomato base|
|Note: To find out if common products contain allergens, it is important to read the labels and contact the manufacturer. Food allergen labelling regulations apply only to packaged foods; they do not apply to non-food products.|
Resources for people with fish, crustaceans and molluscs allergy
- The Association of Allergists and Immunologists of Québec
- Health Canada
- American College of Allergy, Asthma and Immunology
- Subscribe for free to food recall notices from MAPAQ (in French) and the Canadian Food Inspection Agency
- World Allergy Organization
 Soller, S et coll. (2015). Adjusting for nonresponse bias corrects overestimates of food allergy prevalence. Journal of Allergy and Clinical Immunology, 3(2), 291-293. DOI 10.1016/j.jaip.2014.11.006
 Office québécois de la langue française (2014). Fiche terminologique : fruits de mer. Repéré à http://gdt.oqlf.gouv.qc.ca/ficheOqlf.aspx?Id_Fiche=19052998
 Dufresne, C. (2009). Vivre avec les allergies alimentaires : un guide complet pour comprendre et prévenir les réactions allergiques. Montréal, Québec : Les éditions La Presse, 253 p.
 Agence canadienne d’inspection des aliments (2012). Faits sur la salubrité des aliments : Intoxication par des scombroïdes (scombroïdose). Repéré à http://www.inspection.gc.ca/aliments/information-pour-les-consommateurs/fiches-de-renseignements-et-…