Flu vaccines may contain harmless levels of formaldehyde

26 September 2022
What was claimed

The flu vaccine is contaminated with formaldehyde and polysorbate 80.

Our verdict

Some flu vaccines contain trace amounts of formaldehyde, but not enough to do any harm. Some also contain small amounts of polysorbate 80, but this widely used food additive is only potentially harmful to those with a rare allergy to it.

A post on Facebook says: “Elderberries are contaminated with formaldehyde and polysorbate 80. Jk… that’s the flu shot.”

Some flu vaccines used both in the US and UK do contain trace amounts of formaldehyde but not enough to do any harm. Some also contain small amounts of polysorbate 80, which is safe unless someone has an allergy to the chemical.

Misleading information about these chemicals, and others, being present in vaccines is a common occurence online and we have written about such claims multiple times before

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Although it may sound ominous, formaldehyde in the amounts found in vaccines is not dangerous.  

It’s found naturally in lots of living things, including humans and fruit. The amount of natural formaldehyde found in a two-month-old infant’s blood is ten times the amount found in any vaccine. Also, it breaks down quickly in water, and most of a vaccine is water.

Formaldehyde is a naturally-occurring chemical commonly used as a raw material to make other chemicals for industry, especially in creating glues for engineered wood products like MDF and plywood, as well as household cleaners, paints, pesticides and medicinal and personal care products.

Formaldehyde can be dangerous in much larger amounts than are found in vaccines, which usually only happens to those working in industries where they are exposed to large amounts of it over a period of years.

In the US, there are several different flu vaccines available for the 2022/23 season.  Formaldehyde is also used in the production of some of these flu vaccines.

Certain flu vaccines used in the UK may also contain traces of formaldehyde. Other vaccines, like the Hepatitis B vaccine, the pre-school booster and the 6-in-1 vaccine may also contain trace amounts. 

Formaldehyde is used in the manufacturing process of these vaccines to kill the virus or inactivate toxins.

Polysorbate 80

Polysorbate 80 is a chemical used in food, cosmetics and medicines as an emulsifier, which holds different ingredients together. 

It is an ingredient in some flu vaccines used in the US and the UK, as well as several other vaccines, including the AstraZeneca Covid-19 vaccine and HPV vaccine. 

People can be allergic to polysorbate 80, and have allergic reactions to it or similar chemicals. However, this is very rare

Polysorbate 80 has been used for decades to make ice cream melt slower and give a smooth texture. Ice cream contains far more polysorbate 80 than vaccines do.

Image courtesy of Steve Lieman

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