30 Ingredients to Avoid in Personal Care Products

June 03 2026, by Hello Charlie Blogs, 16 min reading time

Reading a personal care label can feel like decoding another language. Long chemical names are easy to distrust, while words such as “natural”, “clean” and “organic” can feel reassuring. Neither reaction tells you whether a product is suitable for you.

A better question is: what is this ingredient doing, how much am I exposed to, and is there a good reason for me to avoid it? A rinse-off cleanser is different from a leave-on cream. A trace manufacturing impurity is different from an intentionally added ingredient. And a substance that can cause harm at a high occupational exposure is not automatically dangerous at the concentration used in a finished cosmetic.

In Australia, most cosmetic ingredients are regulated as industrial chemicals by the Australian Industrial Chemicals Introduction Scheme (AICIS). Therapeutic products, including primary sunscreens and many skin-lightening treatments, sit under the Therapeutic Goods Administration (TGA). Cosmetic labels must also follow Australia’s mandatory ingredient-labelling standard.

Hello Charlie takes a deliberately cautious approach. Our Ingredients Policy excludes ingredients we are not comfortable recommending to families, even where a restricted use may still be lawful. This guide explains that choice without pretending every ingredient on the list presents the same level of risk.

The short version: pay closest attention to ingredients linked to a known allergy, unregulated products, formaldehyde-releasing hair treatments, mercury-containing skin lighteners and products used in ways the label does not recommend. For many other ingredients, concentration, product quality and how you use the product matter more than the name alone.

Ingredients with a stronger reason for caution

1. Formaldehyde, formalin and methylene glycol

Formaldehyde is a known inhalation hazard and can also irritate the eyes, airways and skin. The most important cosmetic exposure is not usually an everyday lotion; it is a hair-smoothing product that releases formaldehyde gas when heated. The US Food and Drug Administration (FDA) advises checking professional and at-home straightening products for names such as formaldehyde, formalin and methylene glycol. If a treatment releases strong fumes or causes burning eyes, coughing or breathing difficulty, stop and move to fresh air. Salon ventilation matters.

2. Bronopol

Bronopol (2-bromo-2-nitropropane-1,3-diol) is a preservative and formaldehyde releaser. Preservatives protect water-based products from bacteria and mould, but this one can be a problem for people with formaldehyde allergy or sensitive skin. If you have confirmed contact allergy, check leave-on products especially carefully and follow your clinician’s avoidance list.

3. DMDM hydantoin

DMDM hydantoin is another preservative that releases small amounts of formaldehyde over time. That does not make every shampoo containing it acutely toxic, but it can trigger allergic contact dermatitis in a sensitised person. The FDA includes DMDM hydantoin among common cosmetic allergens. If you repeatedly develop an itchy scalp, rash around the hairline or eyelid irritation, stop guessing and ask a GP or dermatologist whether patch testing would help.

4. Diazolidinyl urea

Diazolidinyl urea is also a formaldehyde-releasing preservative. The practical concern is skin sensitisation rather than the claim that one use of a lotion causes cancer. People with a known formaldehyde allergy may need to avoid it, along with related preservatives such as imidazolidinyl urea and sodium hydroxymethylglycinate. The European Commission’s Scientific Committee on Consumer Safety has specifically reviewed how low free-formaldehyde levels should be labelled to protect sensitised consumers.

5. Mercury compounds, including thimerosal

Mercury should not be present in ordinary skin-lightening creams. Illegally imported or poorly labelled lighteners remain a concern because mercury can accumulate in the body and harm the kidneys and nervous system. Thimerosal is a mercury-containing preservative with tightly limited uses in some jurisdictions; it is not a routine reason to avoid all eye makeup. Avoid unlabelled lightening products, products with incomplete ingredient lists and products purchased from sellers you cannot trace.

6. Hydroquinone

Hydroquinone is not simply a “toxic cosmetic ingredient”; it is an effective treatment for some pigmentation conditions and should be treated like an active medicine. In Australia, skin-whitening products containing hydroquinone can be regulated as therapeutic goods, and products containing 2% or more require a prescription. The safest approach is to use a properly supplied product under professional guidance rather than an unregistered cream bought through an overseas marketplace.

7. Lead and lead compounds

Lead is a neurotoxic metal with no useful role as an intentionally added everyday cosmetic ingredient. The modern issue is more often contamination in pigments, traditional eye products or poorly controlled imports. Because a contaminant may not appear on the ingredient list, “lead” is not always something you can screen for by label alone. Buy cosmetics from reputable suppliers that follow Australian requirements, and avoid unlabelled kohl, surma or similar products of uncertain origin.

8. Coal tar and coal-tar hair dyes

“Coal tar” can describe different things. Medicinal coal-tar preparations may be used for psoriasis or dandruff, while “coal-tar hair dye” is a regulatory category that now includes many synthetic dyes made from petroleum. The FDA says it does not have reliable evidence linking hair dyes currently on the US market with cancer, but hair dyes can still cause serious allergic reactions. Follow the product warning, perform the instructed skin test and never use scalp hair dye on eyebrows or eyelashes.

9. Cocamide DEA

Cocamide DEA is used to thicken formulas and boost foam. Concerns centre on irritation and the possible formation or presence of nitrosamines when formulation and manufacturing controls are poor. Choosing a cocamide DEA-free cleanser is a reasonable precaution, particularly if you have reactive skin, but “DEA-free” does not by itself make the rest of a formula gentle.

10. Ethanolamines: DEA, MEA and TEA

Diethanolamine (DEA), monoethanolamine (MEA) and triethanolamine (TEA) help adjust pH, emulsify oils or create foam. They are not interchangeable, and their safety depends on concentration, purity and the other ingredients in the formula. A key manufacturing concern is avoiding combinations that form nitrosamines. People with sensitive skin may prefer simpler formulas, while manufacturers should apply appropriate impurity controls rather than relying on a marketing claim alone.

Ingredients where sensitivity, inhalation or product type matters

11. Benzalkonium chloride

Benzalkonium chloride is an antimicrobial and preservative used in some cleansers, wipes and specialty products. It can irritate skin and eyes and can cause contact allergy in some people. Frequent use, damaged skin and leave-on exposure deserve more caution than occasional use in a well-formulated rinse-off product. If a product stings or worsens eczema, stop using it rather than trying to “push through”.

12. Fragrance, parfum and aroma

Fragrance can include many individual materials under a single label term. Most people use fragranced products without a problem, but fragrance is a common cause of cosmetic allergy and can aggravate symptoms in people with fragrance sensitivity or asthma. “Natural fragrance” and essential oils can also contain allergens. If you are choosing for a baby, eczema-prone skin or a household with fragrance sensitivity, a genuinely fragrance-free formula is the simplest option.

13. Benzyl acetate

Benzyl acetate is a fragrance material and solvent with a sweet, floral scent. It is not the same ingredient as benzyl alcohol, and the two should not be treated as though they have identical risk profiles. The sweeping claim that cosmetic exposure to benzyl acetate causes pancreatic cancer is not supported well enough to present as fact. The more practical reason to avoid it is a known fragrance sensitivity or a preference for fragrance-free products.

14. Sodium lauryl sulfate and sodium laureth sulfate

Sodium lauryl sulfate (SLS) and sodium laureth sulfate (SLES) are effective cleansing surfactants. SLS can be drying or irritating, particularly in a strong formula or with frequent exposure. SLES is often milder, although its manufacture can create trace 1,4-dioxane unless that impurity is controlled. Neither ingredient is accurately described as a proven human carcinogen. If your skin feels tight, itchy or sore after washing, a milder sulfate-free cleanser may suit you better.

15. Resorcinol

Resorcinol is used in some oxidative hair dyes and professional colour products. It can irritate or sensitise the skin, so the product directions and allergy alert test matter. Do not use hair colour on broken or inflamed skin, and do not assume a previous trouble-free application guarantees that a reaction cannot occur later.

16. Talc

Talc deserves a careful, non-alarmist explanation. Asbestos-contaminated talc is a serious hazard. In 2024, the International Agency for Research on Cancer classified talc as “probably carcinogenic to humans” based on a combination of limited human evidence, sufficient animal evidence and mechanistic evidence. That classification identifies a hazard; it does not measure the risk from every finished product. Choose products from suppliers with strong contamination controls, avoid inhaling loose powder and consider a talc-free option if you prefer a simpler precaution.

17. Toluene

Toluene is a volatile solvent associated mainly with nail products. High or repeated inhalation exposure can affect the nervous system, while direct contact can irritate and dry the skin. The practical controls are simple: choose a toluene-free polish if available, use nail products in a well-ventilated space, close bottles promptly and keep children away from fumes.

18. Xylene

Xylene is another volatile solvent that may appear in nail products or be encountered in occupational settings. Headache, dizziness and irritation are linked primarily to substantial vapour exposure, not merely seeing the name on a compliant product label. Reduce inhalation, avoid using solvent-heavy products in a small closed room and stop if you feel unwell.

19. Butyl acetate

Butyl acetate helps nail polish spread smoothly and dry to an even film. Its vapour can cause irritation, headache or dizziness at sufficient exposure, and it is flammable. That makes ventilation, sensible storage and careful use important. It does not justify describing every trace exposure as a long-term systemic toxin.

20. Triclosan

Triclosan is an antimicrobial ingredient whose permitted uses and concentrations vary by product and country. European scientific reviewers have found some uses safe at specified concentrations and others unsuitable, particularly when exposure from multiple products is combined. Unless you need a product for a specific therapeutic purpose, there is usually little reason to seek triclosan in an everyday wash. Plain soap and water remain a sound default for routine handwashing.

Ingredients that are often oversimplified online

21. Aluminium compounds

Aluminium salts reduce sweat in antiperspirants; deodorants control odour but do not necessarily reduce perspiration. Current evidence does not support stating that antiperspirant aluminium causes breast cancer or Alzheimer’s disease. In 2024, the European Commission’s Scientific Committee on Consumer Safety concluded that aluminium compounds were safe in the cosmetic uses and maximum levels it assessed. Choosing an aluminium-free deodorant is still a valid preference, but it should not be sold through a claim that the evidence does not support.

22. BHA and BHT

Butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) are antioxidants that help stop oils from becoming rancid. Hazard findings at high experimental doses are often repeated without the exposure context of a finished cosmetic. Regulators assess each substance, product type and concentration separately. Hello Charlie may choose not to stock them under a precautionary policy, but it is more accurate to say there are ongoing hazard and exposure questions than to call both proven human endocrine disruptors or carcinogens.

23. Parabens

Parabens are preservatives, and they are not all the same. Methylparaben, propylparaben and butylparaben have different safety limits. Recent European scientific opinions concluded that methylparaben is safe up to specified concentrations and that propylparaben is safe at a lower maximum concentration, while acknowledging the need to assess potential endocrine activity. The presence of parabens in breast tumour tissue did not prove that parabens caused the tumours. A paraben-free choice is reasonable, but a water-based product still needs an effective preservation system.

24. PEG compounds and ethoxylated ingredients

Polyethylene glycols (PEGs) and ingredients with names such as “laureth” or “ceteareth” can act as emulsifiers, humectants or surfactants. The concern most often raised is 1,4-dioxane, a manufacturing by-product rather than an intentionally added cosmetic ingredient. The FDA reports that manufacturing changes have substantially reduced detected levels over time, and international assessments have considered trace levels at or below 10 parts per million acceptable. This is principally a quality-control question, not proof that every PEG-containing product is unsafe.

25. Phthalates

“Phthalates” describes a family, not one ingredient. Some members, including DBP and DEHP, have stronger reproductive-toxicity concerns and are restricted in various uses. Diethyl phthalate (DEP), historically used in fragrance, has a different evidence profile; the FDA says it does not have a safety concern with DEP as currently used in cosmetics and fragrances. If you want to reduce possible undisclosed fragrance exposure, choose fragrance-free products rather than assuming every product contains the same phthalate.

26. Mineral oil and petrolatum

Highly refined cosmetic- or pharmaceutical-grade mineral oil and petrolatum are not the same as untreated petroleum materials. Properly refined grades are effective occlusives that reduce water loss and are useful for many people with dry or sensitive skin. The cancer concern relates to inadequately refined materials and contaminants, not every jar of compliant petrolatum. You may still avoid petroleum-derived ingredients for environmental or personal reasons; just be clear that this is different from claiming refined mineral oil is inherently carcinogenic.

27. Retinol, retinyl palmitate and retinyl acetate

Vitamin A derivatives can improve acne and signs of photoageing, but they can also cause dryness, peeling and irritation. More is not always better. European reviewers have assessed retinol and certain esters as safe within defined concentration limits while noting that cosmetics add to vitamin A exposure from food and supplements. Introduce a low-strength product gradually, use sun protection and ask a health professional before using a retinoid if you are pregnant, breastfeeding, planning pregnancy or receiving acne treatment.

28. UV filters, including oxybenzone and octinoxate

UV filters should not be grouped together as ingredients everyone must avoid. In Australia, therapeutic sunscreens can use permitted active ingredients subject to TGA requirements and ongoing review. The TGA’s current advice is that sunscreen’s benefits continue to far outweigh its risks. If a particular filter irritates your skin, try another regulated sunscreen—such as a zinc oxide formula—rather than skipping sun protection. Shade, clothing, a hat and sunglasses should remain part of the plan.

29. Synthetic colours

A colour being synthetic does not automatically make it unsafe, just as a plant-derived colour is not automatically non-allergenic. Approved colour additives are controlled for their intended uses, while unapproved dyes and contamination are legitimate concerns. Check for a complete ingredient list and avoid unlabelled novelty makeup, counterfeit products and colours not intended for use around the eyes.

30. Tetrasodium EDTA

Tetrasodium EDTA binds metal ions, helping a formula stay stable and allowing preservatives to work effectively. It can irritate at unsuitable concentrations, but it has low skin absorption and is not usually one of the highest-priority ingredients for a consumer to avoid. Some brands exclude it because of formulation philosophy or environmental persistence concerns. If your goal is a gentler routine, the full formula and your skin’s response tell you more than this ingredient alone.

How to read a personal care label without becoming overwhelmed

Start with your own non-negotiables. A diagnosed allergy, eczema, asthma, pregnancy or a child’s age is more useful than a generic “toxic ingredient” list.
Check the complete INCI list. In Australia, cosmetic ingredients must be available at the point of sale and are generally listed in descending order, subject to the rules for lower-concentration ingredients and colours.
Consider how the product is used. Leave-on, spray, powder, heated and eye-area products can create different exposures from rinse-off products.
Look for a traceable supplier. A clear label, batch information, realistic claims and a business you can contact are more meaningful than a leaf icon or the word “clean”.
Change one product at a time. If your skin reacts, a simple routine makes the trigger much easier to identify.
Do not ignore symptoms. Stop using a product that causes persistent burning, swelling, hives, breathing symptoms or a worsening rash. Seek urgent help for breathing difficulty or facial swelling.

What “natural”, “organic” and “non-toxic” do—and do not—tell you

Natural ingredients are still chemicals, and they can still irritate, sensitise or be unsuitable for babies and pregnant people. Essential oils, for example, can contain well-known fragrance allergens. At the same time, a synthetic ingredient may be highly purified, well studied and useful at a low concentration.

That does not make ingredient standards meaningless. It means a good standard should be transparent about what it excludes and why. You can read more about how Hello Charlie chooses products, our broader Toxins Policy and the ingredients we choose to avoid.

Frequently asked questions

Does a long or unpronounceable ingredient name mean it is harmful?

No. Ingredient names follow standard naming conventions, and even familiar substances can have long technical names. Focus on evidence, exposure and whether the ingredient is suitable for the person using it.

Are products labelled “paraben-free” or “sulfate-free” automatically safer?

No. Those claims tell you what is absent, not whether the replacement preservative or surfactant suits your skin. Read the whole formula and pay attention to how your skin responds.

Should I avoid sunscreen because it contains chemical UV filters?

No. Australia’s TGA states that sunscreen’s benefits outweigh the risks. If you dislike or react to one formula, choose another regulated product rather than leaving skin unprotected.

What is the best option for very sensitive skin?

Look for a short, fragrance-free formula made for the way you intend to use it. Patch-test as directed, introduce one product at a time and seek professional advice for persistent dermatitis or suspected allergy.

This article provides general educational information and is not medical advice. Ingredient rules and scientific assessments can change. Always follow the product label and seek personalised advice from a qualified health professional when needed.