Mustard | whatsinit

About

What it is and where it shows up.

Mustard is a spice and condiment derived from the seeds of Brassica plants (principally Sinapis alba/white mustard, Brassica nigra/black mustard, and Brassica juncea/Chinese or brown mustard), used whole, ground, or in prepared condiment form for its pungent flavour. Its characteristic heat arises from volatile isothiocyanates—primarily allyl isothiocyanate—released when seeds are crushed and moistened by enzymatic action.

Safety summary

The regulatory and scientific consensus.

Mustard is a recognised food allergen in the EU, UK, and Canada, capable of triggering reactions ranging from mild urticaria to life-threatening anaphylaxis, with a self-reported prevalence of approximately 3% in Europe. Expressed (fatty) mustard oil contains 20–40% erucic acid, linked to cardiac lesions in animal studies and subject to a US FDA import alert as an unsafe food additive. In normal culinary quantities, mustard poses no significant risk to non-allergic, healthy individuals, and no Acceptable Daily Intake has been established for mustard as a general spice ingredient.

Regulatory landscape

What food-safety regulators have decided.

Jurisdiction	Status	Note
FDA (Food and Drug Administration) (United States)	Restricted	Expressed mustard oil (fatty, cooking-grade oil) containing 20–40% erucic acid is classified as an unsafe food additive under Section 409 of the FD&C Act and is subject to Import Alert 26-04 (updated April 2026). High erucic acid intake is associated with cardiac lesions in test animals. Volatile mustard oil used solely as a flavouring agent is not covered by this restriction.source
Health Canada (Canada)	Approved	Mustard is identified as a priority allergenic food under the Canadian Food and Drug Regulations (regulatory amendments published in the Canada Gazette Part II on December 14, 2016). Mandatory declaration using the common name on all prepackaged food labels is required. Canada's allergen list extends beyond the US FALCPA eight to include mustard, sesame, sulphites, and triticale.source
EFSA (European Food Safety Authority) (European Union)	Approved	Mustard and products thereof are listed as one of the 14 mandatory food allergens in Annex II of Regulation (EU) No 1169/2011 on the provision of food information to consumers. Mustard presence must be typographically emphasised in the ingredients list on all food labels. Inclusion was based on EFSA scientific opinions confirming mustard as a public health concern in EU Member States (EC Directive 2003/89/EC, EFSA 2004).source
Food Standards Agency (FSA) / Food Standards Scotland (FSS) (United Kingdom)

Who should approach with care

Whose guidance would steer them away.

Other — Individuals with a confirmed mustard allergy must strictly avoid mustard and products thereof, as exposure—even to trace amounts—can trigger severe IgE-mediated reactions including anaphylaxis; mustard is a mandatory labelled allergen in the EU, UK, and Canada precisely for this reason.

Children — Children with mustard allergy carry the same anaphylaxis risk as adults; EU Regulation (EU) No 1169/2011 and Canadian Food and Drug Regulations both require mandatory allergen declaration to protect this population.

Heart Disease — Expressed (fatty) mustard oil contains 20–40% erucic acid, which is associated with cardiac lesions in animal studies; the FDA has issued Import Alert 26-04 deeming such oil an unsafe food additive, making it particularly inadvisable for individuals with pre-existing cardiac conditions.

Pregnancy — Expressed mustard oil high in erucic acid should be avoided during pregnancy given FDA safety concerns; culinary quantities of mustard seed or powder are generally considered safe, but concentrated mustard seed extracts or supplements warrant caution.

Research citations

The sources behind this verdict.

1EFSA. Food Allergens – European Food Safety Authority. efsa.europa.eu
2FDA. Import Alert 26-04: Detention Without Physical Examination of Mustard Oil Containing Unsafe Levels of Erucic Acid, 2026. accessdata.fda.gov
3PubMed. Global Perspectives on Allergen Labeling: Harmonization of Regulations and Practices, 2025. pmc.ncbi.nlm.nih.gov
4PubMed. Re-evaluation of behenic acid from mustard seeds to be used in the manufacturing of certain emulsifiers pursuant to Article 21(2) of Regulation (EU) No 1169/2011 – for permanent exemption from labelling, 2023. pmc.ncbi.nlm.nih.gov
5FDA. CPG Sec 525.575 Prepared Mustard – Composition, 2015. fda.gov

Independently researched5 citations