What Is Sulphur Dioxide? Am I Allergic To It?

Sulphur dioxide is a colourless gas that is commonly used as a food additive. It can be found in processed meat products such as sausages, burgers, dried fruits, and some types of cheese, such as parmesan.

It is usually used as a preservative. It can also be found in some types of wine and soft drinks, such as sherry. It is also an important industrial chemical. As well as being used in the food industry, it is used to make paper, textiles and medicines.

Sulphur dioxide allergy symptoms are most common when it is inhaled or ingested, but they can also occur when someone comes into physical contact with it.

How do you know if you are allergic to Sulphur dioxide?

Symptoms of a sulphur dioxide allergy depend on how the body comes into contact with it. This includes swallowing or breathing it in, or on the skin.

Many people can eat or drink small amounts of sulphur dioxide without having any problems at all.

As with most allergies, the symptoms that someone has when they are allergic to sulphur dioxide will depend on how their body reacts to it. It is very unlikely that you will have an allergic reaction after eating a tiny amount if you do not have an intolerance or allergy.

When you eat or drink sulphur dioxide, the symptoms of an allergy generally occur quickly and can include:

- Sore throat

- Swelling of the face, lips and tongue. This can make it difficult to swallow or breathe for some people

The symptoms of a sulphur dioxide allergy may also affect other parts of the body, including:

- Skin rashes or itching

- Raised red spots on the skin (known as hives)

- Swelling inside the mouth and throat. This may cause a feeling of tightness in your throat or make it difficult to swallow. In very rare cases, someone may go into shock. This is a medical emergency and needs immediate treatment to prevent someone from slipping into unconsciousness.

In addition, the symptoms of a sulphur dioxide allergy may be similar to the symptoms that someone has if they come into contact with pollen, such as hay fever.

How common is a Sulphur Dioxide allergy?

It depends where you live and what foods you eat. The sulphur dioxide in various wines and sherry is not usually a problem for people. At the moment, is it though that less than 2% of the general UK population experiences a sulphite sensitivity, however, this rises between 5 and 13% in asthmatics. 1

This figure may be higher for children than adults. “Children may be more sensitive to the effects of sulphur dioxide due to their smaller size. It is unknown whether sulphur dioxide causes harm to the unborn child.” 2

How can you tell if you are allergic to Sulphur Dioxide?

A doctor or allergist may be able to diagnose a sulphur dioxide allergy by carrying out skin tests or blood tests. They can test for both an allergy and an intolerance. If you have any concerns about potential allergies please seek medical advice and visit your GP.

It’s important for businesses to provide as much information on potential allergens within their products. A simple and effective way to show what allergens are in your menu items is by using Allergen Checkers' management software.

The information provided in this blog is purely informational. Please speak to your GP for further information on any concerns you have regarding allergies. Some of our sources for information are: 

1- https://www.allergyuk.org/resources/sulphites-and-airway-symptoms-factsheet/ 

2- https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/318234/hpa_Sulphur_dioxide_General_Information_v1.pdf