Sulphites, sodium benzoate, calcium chloride, Apeel…

Preservatives are commonly used on fruits and vegetables to extend their shelf life and maintain their appearance. While these chemicals help reduce food waste and ensure a stable supply of produce, they may also pose potential health risks.

In this article, we’ll explore some of the most common preservatives used on fruits and vegetables and the harm they may cause.

Sulphites

Sulphites, including sulphur dioxide, are widely used as preservatives in dried fruits such as apricots, raisins, and prunes, as well as in some fresh produce like grapes and potatoes.

They prevent discoloration, inhibit bacterial growth, and extend shelf life. They work by releasing sulphur dioxide gas, which acts as an antimicrobial agent.

In the UK, sulphites are regulated by the Food Standards Agency (FSA) and must be declared on labels if present above 10 mg/kg, as they can trigger adverse reactions in sensitive individuals.

However, sulphites can cause allergic-like reactions in some people, particularly those with asthma or sulphite sensitivity. Symptoms may include wheezing, chest tightness, coughing, difficulty breathing, hives, itching, swelling, and in severe cases, anaphylaxis.

According to Allergy UK, sulphites can irritate the airways, leading to breathing problems, especially in people with underlying asthma or allergic rhinitis. Anaphylaxis UK notes that inhaling sulphur dioxide from sulphite-containing foods can exacerbate these issues.

While most people tolerate sulphites well, sensitive individuals—estimated at around 1-5% of asthmatics—may experience reactions even at low levels.

The British Journal of Diseases of the Chest has indicated that sulphites can induce asthma in those sensitive to them, though they are considered safe for the general population when used within legal limits [1] [2].

Sodium Benzoate

Sodium benzoate (E211) is a common preservative added to fruit juices, jams, pickled vegetables, and some processed fruits like canned pineapple or fruit salads to prevent microbial growth and spoilage. It occurs naturally in small amounts in fruits such as apples and cranberries but is synthesised for commercial use.

In the UK, it’s approved by the FSA with maximum permitted levels, such as 150 mg/l in non-alcoholic drinks, to ensure safety. While generally recognised as safe in regulated amounts, concerns have been raised about potential health risks.

When sodium benzoate combines with ascorbic acid (vitamin C), it can form benzene, a known carcinogen linked to leukaemia and other cancers. This reaction is more likely under heat or light exposure, as seen in some soft drinks.

Additionally, studies suggest sodium benzoate may contribute to hyperactivity in children, as part of artificial food colourants and preservatives, according to a systematic review in Archives of Disease in Childhood.

Other research indicates possible links to DNA damage, hormone disruption, reduced fertility, faster ageing, and degenerative diseases like Parkinson’s. These effects are typically observed at high doses not common in everyday consumption.

The Environmental Working Group highlights these risks, recommending moderation, while the FSA monitors levels to minimise exposure [3] [4] [5].

Calcium Chloride

Calcium chloride (E509) is frequently used as a firming agent in canned fruits and vegetables, such as tomatoes, potatoes, and apples, to maintain texture and prevent softening during processing. It’s also added to some fresh produce like cucumbers for pickling or to enhance crispness in pre-cut fruits.

As a source of calcium, it can contribute to dietary intake, but in food applications, it’s primarily for preservation.

In the UK, it’s approved by the FSA as a safe additive with no specified maximum level when used in good manufacturing practice. Direct harm from calcium chloride in food is rare at typical levels, but excessive intake could lead to gastrointestinal irritation, such as stomach pain, vomiting, or diarrhoea.

In extreme cases, it may contribute to high blood pressure or cardiovascular issues due to its chloride content.

If ingested in concentrated form (not typical in foods), it may cause burns to the mouth, throat, and stomach, along with low blood pressure. A study in Zebrafish models suggested potential toxic effects on development and cardiac/neural systems at high doses.

But human data from the Institute of Medicine (IOM) indicates insufficient evidence for an upper limit based on cardiovascular risks alone. Overall, it’s considered safe in food quantities, with the FSA ensuring levels pose minimal risk.

Those with kidney issues or on low-sodium diets should be cautious [6] [7] [8].

Apeel

Apeel is an innovative plant-based coating applied to fruits and vegetables like avocados, citrus, apples, and cucumbers to extend shelf life by creating a protective barrier against moisture loss and oxidation.

Developed by Apeel Sciences, it’s made from monoglycerides and diglycerides derived from the peels, seeds, and pulp of fruits and vegetables, mimicking natural cuticles.

In the UK, it has been trialled by retailers like Tesco (which ended its trial in 2023), and it’s approved as safe by the FSA and EU regulations for use on certain produce.

While marketed as a natural, edible alternative to synthetic preservatives, some concerns exist regarding potential health effects. The coating may trigger allergic reactions in sensitive individuals, such as those with lipid allergies, leading to symptoms like itching or swelling.

Long-term effects of regular consumption haven’t been extensively studied. Misinformation has circulated online confusing Apeel’s safety data sheet (intended for industrial handling) with food safety risks—claiming toxicity from heavy metals or solvents.

Apeel Sciences refutes this, as the final product is purified and free of such contaminants. Fact-checks from AP News and The Journal confirm it’s safe when used as intended, with no evidence of harm at consumption levels.

However, environmental and health advocates call for more transparency on its impact, and the FSA monitors emerging data to ensure consumer safety [9] [10] [11].

Minimising Your Exposure to Preservatives

To reduce your exposure to preservatives in fruits and vegetables, consider the following tips:

• Choose fresh, whole produce whenever possible, as it is less likely to contain preservatives.
• Read labels carefully and opt for products with minimal or no added preservatives, checking for E-numbers like E220 (sulphites) or E211 (sodium benzoate).
• Support local farmers and buy produce in season, as it often requires fewer preservatives due to shorter transportation and storage times—explore options through community schemes like our Community Home Growers Project.
• Rinse fruits and vegetables thoroughly under running water to remove surface preservatives and residues, or peel where appropriate.
• Grow your own fresh, preservative-free greens at home with sustainable methods. Microgreens, for instance, offer a nutrient-dense alternative packed with up to 40 times more vitamins and antioxidants than mature vegetables, without any chemical preservatives. Discover how in our complete beginner’s guide to growing microgreens, or start with our easy subscription kits and GrowGarden™ systems.
• Incorporate microgreens into your diet for natural nutrition—explore their benefits in our ultimate guide to microgreens, or try recipes from our collection of over 20 delicious ideas. For targeted health support, see how they aid wellness in our lifestyle benefits guide, or during pregnancy in this dedicated article.
• Shop from companies like Skye Mountain that prioritise organic, preservative-free growing practices—browse our full range of microgreen products, including bundles like the Sulforaphane-Rich Bundle for antioxidant boosts.

While preservatives play a role in maintaining the safety and quality of our food supply, it’s essential to be aware of the potential health risks associated with these chemicals, especially for vulnerable groups like asthmatics or children.

By making informed choices, such as opting for home-grown microgreens, and supporting sustainable, preservative-free farming practices, you can help minimise your exposure and promote a healthier, more natural diet.

For more on sustainable growing and its benefits, visit our blog or learn about our mission.

Discover Preservative-Free Alternatives with Skye Mountain

At Skye Mountain, we’re passionate about empowering you to grow and enjoy fresh, nutrient-rich microgreens at home—completely free from preservatives and packed with natural goodness.

Our eco-friendly products make it easy to start your own sustainable garden, whether you’re a beginner or looking to scale up.

For instance, our Microgreens Subscription service delivers high-quality, organic seeds straight to your door, allowing you to harvest varieties like broccoli raab, radish, and pea shoots in just 7-10 days.

Enhance your setup with accessories like the Digital Seedling Heat Mat for faster germination, the Mini USB Clip-On Fan for optimal airflow, or our Amber Glass Spray Bottle for gentle misting.

For larger yields, check out our 3-Tier Stainless Steel Grow System or Commercial Microgreen Grow Systems, perfect for kitchens or small businesses.

We also offer themed bundles, such as the Gut Health Bundle for digestive support or the Vitality Bundle for an energy boost.

To get started confidently, refer to our full growing instructions, troubleshooting guide, and FAQs.

If you need personalised help, book a free home growing consultation.

All our products come with a 100% satisfaction guarantee, fast UK deliveries, and alignment with our ethics and compliance policy.

Shop now at our online store and join the movement towards healthier, preservative-free eating. For inspiration, read about why coco coir is ideal for microgreens or how microgreens promote sustainability. Contact us via our support page if you have questions!

References:

1. Anaphylaxis UK. (n.d.). Sulphite Allergy. Retrieved from https://www.anaphylaxis.org.uk/fact-sheet/sulphites/
2. Allergy UK. (2021). Sulphites and Airway Symptoms. Retrieved from https://www.allergyuk.org/resources/sulphites-and-airway-symptoms-factsheet/
3. Environmental Working Group. (2024). What is sodium benzoate? Retrieved from https://www.ewg.org/news-insights/news/2024/02/what-sodium-benzoate
4. ZOE. (2024). Food Preservatives: Do They Impact Health? Retrieved from https://zoe.com/learn/food-preservatives-health
5. Stevenson, J., et al. (2024). Artificial food additives: hazardous to long-term health? PubMed. Retrieved from https://pubmed.ncbi.nlm.nih.gov/38423749/
6. U.S. Food and Drug Administration. (2016). GRAS Notice 634: Calcium Chloride. Retrieved from https://www.fda.gov/files/food/published/GRAS-Notice-000634–Calcium-chloride.pdf
7. de Lima, M. N. M., et al. (2023). Calcium Chloride Toxicology for Food Safety Assessment. PMC. Retrieved from https://pmc.ncbi.nlm.nih.gov/articles/PMC9827598/
8. KHA Online-SDS Management. (2020). The Hazards of Calcium Chloride. Retrieved from https://www.kha.com/everything-to-know-about-the-hazards-of-calcium-chloride/
9. AP News. (2023). Posts misrepresent safety of produce-protecting solution from Apeel. Retrieved from https://apnews.com/article/fact-check-apeel-fruit-produce-safety-sheet-867075775325
10. The Journal. (2023). Debunked: Safety sheet used to show an edible coating is risky. Retrieved from https://www.thejournal.ie/is-apeel-edipeel-bad-for-you-6053914-Apr2023/
11. Wicked Leeks. (2023). Everything you need to know about Apeel. Retrieved from https://wickedleeks.riverford.co.uk/features/everything-you-need-to-know-about-apeel/