CPSR for Natural Deodorant (UK & EU Guide)

Natural deodorant has exploded in popularity baking-soda balms, magnesium sticks and aluminium-free formulas are everywhere. But the underarm is one of the most sensitive, easily irritated areas of the body, which makes deodorant a product where the CPSR really earns its keep. This guide explains what a safety assessment covers for natural deodorant and the issues that most commonly cause trouble.

For the basics of safety assessments, see our guide to what a CPSR is. Here we focus on deodorant specifically.

Is deodorant a cosmetic?

Yes a product applied to the skin to control body odour is a cosmetic under UK and EU law, so a natural deodorant needs the full compliance set including a CPSR. There is, however, an important distinction between a deodorant and an antiperspirant. A deodorant tackles odour, while an antiperspirant reduces sweating, typically using aluminium salts. In some jurisdictions antiperspirant claims are treated differently, but a standard cosmetic deodorant that addresses odour sits squarely within cosmetic rules.

Most “natural” deodorants are deodorants in this sense they neutralise or mask odour and support a less hospitable environment for odour-causing bacteria, rather than blocking sweat. Being clear about which you are making matters, because the claims you make shape both classification and what you must substantiate.

The underarm is sensitive skin

The underarm is warm, occluded, often freshly shaved, and rubbed by clothing a combination that makes it far more prone to irritation than, say, the forearm. A product perfectly comfortable elsewhere can sting or cause a rash here, especially on compromised skin after shaving. This is the central safety theme for deodorant: a formula has to be gentle enough for repeated use on this delicate, easily irritated area.

The safety assessment weighs this carefully, looking at every ingredient through the lens of sensitive, occluded skin and foreseeable use such as application soon after shaving. Ingredients and levels that would be unremarkable in a body lotion deserve more caution in a deodorant.

The baking soda problem

Sodium bicarbonate (baking soda) is the single most common cause of trouble in natural deodorants. It is popular because it genuinely helps neutralise odour, but it is alkaline, and on the sensitive underarm it can disrupt the skin's natural acidity and cause irritation, redness and rashes for a significant number of people. Many of the “natural deodorant gave me a rash” stories trace back to baking soda.

This does not mean baking soda is banned it is the level and the overall formula that matter. Lower inclusion rates, buffering, and gentler alternatives such as magnesium hydroxide are common ways makers reduce the risk. The safety assessment scrutinises baking soda content closely, and a high-baking-soda formula may need reformulating or clear warnings to be considered safe for repeated underarm use.

pH and skin balance

Linked to the baking soda issue is pH. Skin is naturally mildly acidic, and products that are strongly alkaline can disturb this balance and the skin barrier, contributing to irritation. Baking-soda deodorants tend to be alkaline, which is part of why they can be harsh; magnesium- and acid-buffered formulas aim to sit closer to skin-friendly levels.

The assessment considers the product's pH as part of judging tolerability on underarm skin. For makers, measuring and controlling pH and being able to report it is an important part of demonstrating the product is gentle enough. A more skin-compatible pH is one of the levers for making a natural deodorant safer.

Essential oils and fragrance

Natural deodorants are frequently scented with essential oils, both for fragrance and because some have claimed antimicrobial properties against odour-causing bacteria. But essential oils are potent, are rich sources of regulated fragrance allergens, and some can be sensitising, especially on already-sensitive underarm skin. Used too heavily, they can turn a soothing product into an irritating one.

The assessment checks essential oils against safe-use levels and the fragrance-allergen requirements, since a leave-on product like deodorant carries the stricter allergen threshold. Declarable allergens must appear in the ingredient list see our allergen labelling guide. Restraint with essential oils tends to make for both a safer and a more wearable deodorant.

Leave-on means stricter limits

Deodorant is a leave-on product it stays on the skin all day rather than being washed off so it falls under the stricter end of the rules for restricted ingredients and fragrance allergens. Exposure is high and prolonged, on sensitive skin, which is exactly the scenario the stricter leave-on limits are designed for. An ingredient level that would be fine in a rinse-off wash may be too high for a leave-on deodorant.

This is a recurring theme across cosmetics, but it bites particularly hard for deodorant because of the sensitive site and all-day wear. The safety assessment applies the leave-on limits and judges the cumulative exposure, which is why the precise levels of every active and fragrance ingredient matter.

Preservation: balms versus other formats

Whether a natural deodorant needs a preservative depends on its format. A purely anhydrous balm or stick oils, butters, waxes and powders with no water generally does not support microbial growth and often needs no traditional preservative, though an antioxidant may help protect the oils. A deodorant that contains water (some creams or sprays) does need a preservative system and a challenge test.

As ever, the caveat is real world use: a balm applied with fingers from a pot can have water and microbes introduced, which may change the picture. Our preservatives and challenge test guides explain the principles, and the assessor decides what your specific deodorant requires.

Claims to be careful with

Deodorant claims need care. Saying a product controls odour is a normal cosmetic claim. Saying it stops sweating moves toward an antiperspirant claim, which changes expectations and, in some markets, classification. Claims about treating conditions, healing, or medical effects can push the product toward being seen as a medicine well outside cosmetic territory.

Keeping claims clearly cosmetic and supportable protects both your compliance and your customers' expectations. If you want to claim a specific benefit, be ready to support it. The line between a deodorant and an antiperspirant, and between a cosmetic and a medicine, is drawn largely by the claims you make.

Common natural deodorant mistakes

The classic mistake is too much baking soda. Makers chasing strong odour control pack in sodium bicarbonate, and a proportion of customers react with the redness and rashes that have given natural deodorant a difficult reputation. Reducing the level, buffering it, or switching to gentler odour-control ingredients such as magnesium hydroxide is usually the answer. A close second is applying to freshly shaved skin without warning users the combination of a just-shaved underarm and an alkaline or essential-oil-rich product is a recipe for stinging.

Another frequent error is overdoing essential oils, both for scent and for their supposed antibacterial benefit, pushing past comfortable levels on this sensitive site and creating sensitisation risk. And some makers blur the deodorant/antiperspirant line, implying their product stops sweat when it only addresses odour an unsupported claim that can also raise classification questions. Avoiding these pitfalls is largely about restraint: a gentler formula, sensible essential-oil levels, honest claims, and clear use instructions make for a deodorant that is both safer and more pleasant to wear.

It is worth remembering that an irritating deodorant is not just a compliance concern but a commercial one: underarm reactions generate returns, complaints and bad reviews. Getting the formula gentle enough to wear daily, and being upfront about how to use it, protects customers and brand alike. The safety assessment is there to catch the formulation issues before customers do.

Key safety points for deodorant at a glance

Natural deodorant checklist

• Be clear whether you make a deodorant (not an antiperspirant).

• Treat the underarm as sensitive skin in every choice.

• Control baking soda level (or use gentler alternatives) and pH.

• Keep essential oils within safe levels and declare allergens.

• Apply leave-on limits to restricted ingredients and fragrance.

• Preserve water-containing formats and test them.

• Keep claims cosmetic, and have it all assessed in a CPSR.

Frequently asked questions

Does natural deodorant need a CPSR?

Yes. A deodorant is a cosmetic, so it needs a CPSR, PIF, Responsible Person, notification and compliant labelling. The sensitive application site makes the safety assessment especially important.

Why does baking soda cause problems in deodorant?

Sodium bicarbonate is alkaline and can disrupt the skin's natural acidity on the sensitive underarm, causing irritation and rashes for many people. The level and overall formula determine the risk, which the CPSR scrutinises.

What's the difference between a deodorant and an antiperspirant?

A deodorant controls odour; an antiperspirant reduces sweating, usually with aluminium salts. The distinction affects claims and, in some markets, classification, so be clear which you are making.

Can I use essential oils in deodorant?

Yes, within safe levels. Essential oils are potent and allergenic and can sensitise the underarm, so they need careful limits, and declarable fragrance allergens must appear in the ingredient list under the stricter leave-on threshold.

Does deodorant need a preservative?

An anhydrous balm or stick generally does not, though it may use an antioxidant. A water-containing deodorant cream or spray needs a preservative system and a challenge test.

Why are deodorant rules stricter than for a body wash?

Deodorant is leave-on and stays on sensitive skin all day, so exposure is high and prolonged. The stricter leave-on limits for restricted ingredients and fragrance allergens apply.

What claims can I make for a natural deodorant?

Odour-control claims are normal cosmetic claims. Avoid antiperspirant ('stops sweat') claims unless intended, and avoid medical claims, which can push the product outside cosmetic classification. Claims must be supportable.

References: Regulation (EC) No 1223/2009 (EUR-Lex); Annex III restricted substances; fragrance allergen requirements; UK Cosmetics Regulation as retained. General information only, not legal advice.