Citric acid is one of those ingredients you see everywhere—from your favorite snacks to skincare and cleaning products, but it often comes with a cloud of mystery. Is it truly natural? Is it safe to use daily? With the conflicting opinions floating around the internet today, it is more than reasonable to be cautious. Here is an easy-to-reference breakdown about what Citric Acid is and why it is so widely trusted around the globe.
What is Citric Acid?
Citric acid is a weak organic acid (C₆H₈O₇) naturally present in citrus fruits and commonly produced by fermenting sugars. It’s a colorless, water-soluble crystalline solid, valued for its tart taste and its vital role in energy-producing metabolic processes.
Highly versatile, citric acid functions as a chelating agent, pH adjuster, flavor enhancer, preservative, and cleaning aid. Scientific reviews confirm its low toxicity, rapid biodegradability, and minimal environmental impact, and it holds “Generally Recognized as Safe” (GRAS) status by the U.S. FDA with global approval for use in the food and cosmetic industry.
How Citric Acid Is Made (And Why It’s Not as Scary as It Sounds)
Citric acid is a naturally occurring compound found in citrus fruits like lemons, limes, and oranges. It's what gives them their tangy taste! But when it comes to making citric acid for use in foods, cleaning products, or cosmetics, we don’t squeeze millions of lemons.
Citric acid is produced through carefully controlled fermentation using the microorganism Aspergillus niger, and sugar-rich sources like molasses or starch hydrolysates. This microorganism converts sugars into citric acid in optimized, low-impact fermentation systems. The acid is then recovered by precipitating calcium citrate, purified through acidification, and crystallized into the final product. Modern submerged fermentation methods minimize waste, maximize yield, and create a biodegradable, food-grade citric acid that supports sustainable production for food, cosmetic, and cleaning applications.
The use of this efficient fermentation process is similar to how yeast is used to make bread or beer.
The Microbe Behind It: Aspergillus niger
To produce citric acid on a large scale, manufacturers use a tiny, naturally occurring fungus called Aspergillus niger. That might sound alarming, but here’s a helpful way to think about it:
Imagine baking bread — you use yeast, which is also a type of fungus. You wouldn’t eat raw yeast, but once it does its job and the bread is baked, there’s nothing left to worry about. It’s safe, and you’ve enjoyed it a thousand times without giving it a second thought.
The same is true with citric acid production. Aspergillus niger helps convert sugars (like those from corn or beets) into citric acid during fermentation. After that, the citric acid is completely separated, purified, and filtered. The fungus itself never makes it into the final product.
Why This Is a Good Thing
- Sustainable: This process allows citric acid to be made in large amounts without depending on citrus fruit crops, which vary by season and region.
- Consistent and Safe: It's a controlled, food-safe process used around the world and monitored by health and safety agencies.
- Trusted in Everyday Life: The citric acid made this way is the same ingredient you’ve safely used for years in everything from lemonade to laundry soap.
Why Do We Use Citric Acid?
At Rustic Strength, we use citric acid for its natural ability to adjust the pH of our products. Why is this important? pH is a measure of how acidic or alkaline a substance is, on a scale from 0 (very acidic) to 14 (very alkaline). The right pH level in a product isn't just a scientific detail — it’s crucial for safety, performance, and skin compatibility.
Hand Soap (typically contains citric acid to control pH levels)
- Ideal pH Range: ~4.5 to 6.5 (slightly acidic to neutral)
- Why It Matters: Your skin has a natural barrier called the acid mantle, which protects against bacteria, irritation, and moisture loss. This barrier functions best around a pH of 5.5.
- If Too Alkaline: Soap with a high pH (9–10) can strip natural oils, disrupt the skin barrier, cause dryness, irritation, or even make skin more prone to infection.
Laundry Detergent (typically does not contain citric acid)
- Typical pH Range: ~8.5 to 11 (alkaline)
- Why It Matters: Alkaline environments help break down oils, grease, and protein-based stains like sweat and food. High pH also improves surfactant efficiency (the agents that lift and suspend dirt).
Citric acid also acts as a preservative booster, enhancing the effectiveness of the primary preservatives we use. This allows us to use a lower concentration of preservatives while still maintaining product safety and stability.
It also helps create conditions that make it difficult for bacteria and other microbes to thrive, ensuring product quality without the need for harsh preservatives.
You can find citric acid in these Rustic Strength products:
Environmental Concerns, Safety, & Regulatory Information
- Biodegradability: Citric Acid is readily biodegradable and is shown to have very low aquatic toxicity.
- Skin Irritant: Though citric acid has a high eye irritation endpoint, it is shown to cause minimal irritation to skin when used properly.
- EWG Score: Citric Acid typically receives a low hazard score (1-2) from the Environmental Working Group (EWG), indicating very low concern for developmental and reproductive toxicity, allergies and immunotoxicity, and use restrictions.
- EU and Canada Approval: Yes, citric acid is approved for use in cosmetics and personal care products in both the European Union and Canada. Both regions have regulations in place to ensure the safety of cosmetic ingredients.
- CAS Number: 77-92-9.
- EPA Safe List: Citric acid is not typically listed as a chemical of concern or a known environmental hazard. Learn more.
Key Takeaways
- Citric acid (CAS 77929) is a naturally occurring, weak organic acid widely used in food, cosmetics, and cleaning products.
- It’s safe, biodegradable, and globally approved by the FDA, EPA, and health agencies in the EU and Canada.
- Environmentally friendly – breaks down quickly and poses no bioaccumulation risks.
- Plays a key role in product stability by regulating pH and helping prevent microbial growth.
- Sustainably produced through efficient fermentation processes that minimize waste and environmental impact.
- Gentle and versatile – safe for everyday use when formulated properly, with minimal risk of irritation to the skin.
If you have any questions regarding this or any other ingredients we use, feel free to reach out to our email: customercare@rusticstrength.com. We would be more than happy to answer your questions.
Frequently Asked Questions
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Is citric acid approved in the U.S., EU, and Canada?
Yes. It is FDAGRAS in the U.S., exempt under EPA regulations, and universally accepted in the EU and Canada. -
Is citric acid environmentally friendly?
Absolutely. Citric acid biodegrades rapidly (90–100% in standard testing), has low aquatic toxicity, and does not bioaccumulate. -
Does citric acid have any long-term health risks?
No, studies show citric acid is not linked to cancer, genetic damage, or reproductive harm. -
Is citric acid safe for sensitive skin?
Generally, yes. In gentle, pH-balanced products, it’s well-tolerated, though highly concentrated forms can cause irritation.
EPA Safe Ingredient - YES
EWG® Score – 1 - 2
EU and Canada Approved – YES
Plant-based – Yes – Corn
Skin Irritant – mild
Environment Hazard – low
Biodegradable – easily
CAS – 77- 92 - 9
We Invite You to Do Your Own Research
Scientific journals and articles are the foundation of evidence-based decisions at Rustic Strength. Blogs can provide helpful information. However, if they cannot cite scientific articles, their claims stand on little.
SOURCES
- Chelating agent – Citric acid functions as a chelating agent, pH adjuster, flavor enhancer, preservative, and cleaning aid.
- Gras – US EPA, Regulations.gov, EPA Nepis.
- Carefully controlled fermentation – Citric acid production uses carefully controlled fermentation with Aspergillus niger.
- FDA – Citric acid holds “Generally Recognized as Safe” (GRAS) status by the U.S. FDA.
- EPA – Listed on the EPA Safer Chemical Ingredients List.
- EU – Approved in the European Union for use in cosmetics and personal care products.
- Canada – Approved for use by Health Canada.
- Minimal irritation – Causes minimal skin irritation when used properly.
- Readily biodegradable – Citric acid is readily biodegradable with low aquatic toxicity.
- Cancer or reproductive harm – Not linked to cancer, genetic damage, or reproductive harm according to studies.
- Harsh Preservatives – Citric acid helps reduce the need for harsh preservatives.
Other resources to consider
Why Ingredient Transparency Matters at Rustic Strength
Our mission began when our founders, Brandon and Alicia, traced their toddler’s severe allergic reactions back to “safe” household cleaners. Unable to find products that were both gentle and genuinely high-purity, they started formulating their own—free of phthalates, sulfates, 1,4-dioxane, and other hidden irritants.
Today, every Rustic Strength label and product page lists every ingredient—no secrets, no green-washing—so you can choose with confidence and keep harmful chemicals out of your home. See more about what we use and avoid.
Our hope is that by understanding the components of our products, you can make informed decisions about what you put on your skin and in your home, ultimately avoiding a mysterious illness as our son had.
Don’t be fooled by vague marketing. Whether or not you buy from us, we urge you to read labels, research ingredients, and demand full transparency for a healthier family and planet.
Trying to reduce toxins in your home, but don't know where to start? Visit our blog How to Relieve Your Toxin Burden for easy actionable ways to begin investing in your health today.
Still have questions? Feel free to reach out to our email: customercare@rusticstrength.com. We would be more than happy to answer your questions.
