Key points

When choosing skin care products, it’s essential to be mindful of the ingredients they contain. If you want your skin and the rest of your body to stay healthy, you should only choose products with safe and effective ingredients. Unfortunately, our bodies are already exposed to lots of pollutants daily, so we want to avoid putting chemicals that disrupt our endocrine system, obesogens, neurotoxins, developmental toxins, immunotoxins, reproductive toxins, and teratogens on our skin as well. But some skincare companies still use these dangerous chemicals in their products, so you should be mindful of this and always check the ingredient lists before buying new personal care items. 

While there are some personal differences in how different people tolerate different chemicals, there are mny ingredients that are considered to be universally unsafe by experts. We’ve put together a list of 23 potentially harmful ingredients to help you select safe skincare products. 

But before we get to our list, we want to save you some time and tell you that if you’re looking for safe and effective skincare products, you should choose the Dr. Kinsella brand! Our premium-quality products are packed with active ingredients to bring potent anti-ageing effects to your skin. And, of course, they are 100% free from harmful and potentially dangerous chemicals. So don’t waste your time and shop for Dr. Kinsella products today!

And now, let’s look at the list of chemicals you should avoid in skincare.


DBP, DEHP, and DEP are phthalates that belong to the class of plasticising chemicals. These ingredients help fragrances in skincare products stay on the skin for longer and make the texture of products more pliable. But scientific research has found that these ingredients impact the endocrine system and are toxic to our organs. There’s also evidence that they may cause birth defects. Plus, phthalates are also harmful to the environment. While the EU has already banned this family of ingredients from cosmetics, the FDA in the USA still allows its use. 


Homosalate is often used in sunscreens and skin care products with SPF. This ingredient is usually added as a UV light absorber. But doctors say that it may disrupt the endocrine system, and several studies in cells have shown that it may indeed impact hormone levels. Besides direct health concerns associated with this chemical, this ingredient may also increase the absorption of pesticides in the body.


Methylparaben, isobutyl paraben, and propylparaben all belong to the paraben family, a group of preservatives used in skin care products to prevent them from getting contaminated with mould and bacteria overgrowth. However, parabens have been proven to have an effect on the human endocrine system, which means they can disrupt important hormone regulation mechanisms in our bodies. It’s also not uncommon for these ingredients to act as allergens. Butyl, propyl, and ethyl parabens can be found in a variety of cosmetics, and they are some of the most common ingredients you should avoid. Scientists have also found a link between these parabens and breast cancer. 


As you probably know, this chemical is a vitamin A derivative, and it’s also a very common active competent in anti-ageing skincare products. However, some studies indicate that this ingredient may contribute to the development of skin tumours and lesions on the skin as a result of sun exposure. In addition to this, retinol can cause photosensitivity and irritate the skin. Thus, you should avoid using this ingredient during the summer months and stay away from it completely if the area where you live gets lots of sun year-round. Plus, pregnant and nursing women are strictly prohibited from using this ingredient because it can have negative effects on babies.


You should be especially careful to avoid this ingredient, as there are quite a lot of data that prove that it’s extremely harmful. In addition to skincare products, this chemical is also often used as a preservative in makeup products. Studies show that formaldehyde is a carcinogen that may cause asthma, neurotoxicity, and developmental toxicity. It is also considered to be a general irritant to the skin, eyes, and lungs. 

You should also keep in mind that there are many chemicals that release formaldehyde once they are on your skin or in the cells. Some of these ingredients are quaternium-15, imidazolidinyl urea, DMDM hydantoin, diazolidinyl urea, sodium hydroxymethylglycinate, 2-bromo-2-nitropropane-1,3 diol (bronopol), and several other preservatives.


Toluene, which is also referred to as butylated hydroxytoluene or BHT, is a paint thinning solution and a petrochemical solvent, but it’s also a common ingredient in nail polish. Studies have found that toluene raises serious contamination concerns and can irritate skin, eyes, and lungs, as well as cause non-reproductive organ toxicity. On top of that, it can also cause birth defects, so it should be avoided during pregnancy. This chemical is also linked with brain toxicity. The good news is that it’s been banned by the European Union, some countries in Southeast Asia, and some US states. However, it may still be present in some brands of nail polish, nail treatments, and hair dye.


Sodium lauryl sulphate (SLS) is a popular cleansing agent and foam booster, but it’s also a strong irritant. It can irritate the skin, eyes, and lungs as well as provoke allergies. There is evidence that it may be toxic to non-reproductive organs as well as harmful to the environment. It’s most commonly present in body wash, bubble baths, and shampoo.

Sodium laureth sulphate or SLES is used similarly to SLS, as this ingredient acts as a surfactant. It’s often contaminated with 1,4-dioxane, which is a carcinogen used to manufacture other chemicals. This makes this ingredient twice as harmful. SLES can cause skin, eye, and lung irritation, but the research about additional effects that this ingredient may cause with repeated exposure is lacking. So you should strive to use products that are free from SLS or SLES, even though this can be challenging.

Triclosan And Triclocarban

Triclosan and triclocarban are preservatives that combat microbes. They are commonly used both in skin care products and household cleaning supplies. These ingredients cause skin, eye, and lung irritation, and repeated exposure to them causes bioaccumulation or a buildup of these chemicals in the body. Triclosan and triclocarban are known to disrupt the endocrine system, which may cause reproductive and non-reproductive organ system toxicity. Triclosan, in particular, has been proven to impact thyroid and reproductive hormones, which is why it’s banned in many countries. These ingredients are most commonly present in hand sanitisers, antibacterial soap, and toothpaste.


BHA and BHT are synthetic antioxidants used in skin care products and cosmetics to prolong their shelf life. These ingredients are carcinogens that disrupt the endocrine system. There’s also evidence that they may cause liver damage.

Carbon Black

Even though carbon black is banned by many countries as a toxic ingredient, it still can be found in some cosmetic products, such as mascara, eyeliners, and other products. Essentially, it is a black powder that’s added to makeup products to lend them a dark black colour. While some people claim that small doses of carbon black are safe, studies have found that this ingredient may be linked to cancer and neurodevelopmental effects in offspring, and it can also hamper lung function and hormone production. When checking the labels, look for acetylene black, furnace black, channel black, lamp black, and thermal black.


If you see MEA, DEA, and TEA on the label of a product you’re considering buying, you should rethink your decision. These are foam boosters that also adjust the pH. While the number of studies on the side effects of this ingredient family is limited, there are data that shows that it can cause allergies, skin toxicity, hormone disruption, and inhibited fetal brain development. There also may be other effects we are unaware of. These ingredients are most commonly present in cosmetics, fragrances, and sunscreens.


Hydroquinone is a common active ingredient in many drugs, but it’s also present in some fragrances and anti-ageing products. Some companies use it to lighten the skin and slow down melanin production. However, you may be surprised to find out that it’s also an ingredient in paint and super glue. This chemical has been linked to organ toxicity, cancer, and skin irritation. Many people experience bumpy skin after using hydroquinone, while others develop contact dermatitis and sun sensitivity.

Methylisothiazolinone And Methylchloroisothiazolinone

These ingredients are often added to skin care products as preservatives. They’re well-known skin, eye, and lung irritants as well as allergy triggers. Methylisothiazolinone and methylchloroisothiazolinone are most commonly present in hair products such as hair conditioners, shampoo, and body wash.


Octinoxate is another harmful ingredient you may come across when looking for sunscreen. It’s been proven to cause endocrine system disorders and organ toxicity, but it can also impact our bodies at the cellular level. Besides causing concerns for human health, octinoxate is also a suspected environmental pollutant. It can also cause skin irritation which is something you want to avoid, especially if you have sensitive skin.


Lead is a naturally occurring chemical element that has become widely notorious in recent decades, but it’s also still sometimes added to different cosmetic products such as lipsticks, eye shadows, pressed powders, shampoos, and body lotions. There’s evidence that suggests that lead is a carcinogen, and exposure to high levels of this ingredient may cause kidney damage, as well as impact your blood and nervous system. It is among the most important ingredients to avoid in skincare.

Benzalkonium Chloride

Benzalkonium chloride is a disinfecting agent that’s typically included in skincare products as a preservative and surfactant. While it’s most commonly found in household cleaning supplies, it may also be present in products like deodorant and moisturisers. Research shows that this ingredient can cause severe skin, eye, and respiratory irritation and trigger allergies. If you regularly use products containing this antimicrobial agent to clean your home, you should keep in mind that it can cause the growth of resistant bacteria.

Oxybenzone And Avobenzone

Oxybenzone and avobenzone are commonly present in sunscreen. Besides causing skin irritation and allergies, these ingredients may disrupt the hormone system. They are also harmful to the environment. Other harmful effects of oxybenzone and avobenzone are still being studied.


Siloxanes or cyclical silicones are often present in different skincare and cosmetic products. These chemicals are known to cause harm to the environment, but several studies also link these ingredients to endocrine system disorders. 

When checking product labels, you should look for ingredients ending in -siloxane or -medicine. These ingredients are used in skincare to moisten and soften the skin. But they are also suspected of being reproductive toxins. Of all the siloxanes, dimethicone is the only chemical that’s considered safe.


Talcum powder is widely used as a smoothing and matting agent in makeup. It’s not as dangerous as other ingredients on this list, and pure talcum powder can even be considered safe. But unfortunately, this chemical is often contaminated with asbestos – a well-known carcinogen that causes lung disease. So we recommend avoiding this ingredient just to be on the safe side.


PFAs are fluorinated chemicals which are often present in sunscreens, hair products, and shaving creams. Both PFAs and PFCs pose serious health hazards and can cause diseases like cancer and thyroid disease, as well as hamper the effectiveness of vaccines. PFCs are most often found in waterproof mascara because of their water-resistant properties.

One of the most dangerous PFAs is Teflon, or Polytetrafluoroethylene (PTFE), which is sometimes added to cosmetics to improve their texture. It causes hormonal abnormalities and reproductive issues.


Resorcinol is commonly found in hair dye and hair bleaching products. Studies link this ingredient to skin irritation and reduced thyroid function. It also impacts normal immune system functioning. 

Synthetic Colours

Synthetic colours are usually labelled as letters F, D, or C, followed by a number or colour. These ingredients are usually made from petroleum or coal tar sources, which makes them dangerous to our health. Using products with synthetic colours can cause skin irritation, blocked pores, as well as skin inflammation and sensitivity. 

Petroleum Jelly

Petroleum jelly is often added to lotions and different skincare products as a moisturising agent. It’s also a common ingredient in balms, lotions, lip products, and makeup removers. While refined petroleum jelly, also known as mineral oil, isn’t harmful to us, you can never be certain that the ingredient found in your cream or lip balm has been refined properly. 

Poorly refined petroleum jelly may be contaminated with polycyclic aromatic hydrocarbons or PAHs. PAHs are a group of chemical compounds, several of which are classified as carcinogens and skin irritants, so it’s best to avoid products containing this ingredient. Look for the following ingredients on the label: mineral oil, white petroleum soft paraffin, paraffin oil, white mineral oil, and liquid paraffin.


What ingredients are not safe for skin?

When looking for skincare products, you should carefully read the labels and make sure that the product you’re considering doesn’t contain phthalates, homosalate, parabens, retinol, formaldehyde, SLS, toluene, SLES, triclosan, carbon black, ethanolamines, hydroquinone, methylisothiazolinone, methylchloroisothiazolinone, octinoxate, lead, benzalkonium chloride, siloxanes, oxybenzone, avobenzone, talcum, PFAs, PFCs, resorcinol, synthetic colours, and petroleum jelly. These ingredients can cause many diseases when used for a prolonged time.

What are the most harmful ingredients in cosmetics?

The most harmful ingredients you should avoid in skincare and cosmetics are lead, formaldehyde, and its precursors and derivatives, including paraformaldehyde and methylene glycol. Formaldehyde is one of the most dangerous carcinogens that poses a danger to the immune system and can cause different allergic reactions.

What ingredients should not be in moisturisers?

When looking for a moisturiser, search for products that don’t contain synthetic dyes and parabens, as these ingredients cause irritation and burning. It’s also best to avoid ingredients like mineral oil and propylene glycol.

What are the most toxic beauty products?

Deodorant, body wash, body lotion, shampoo, and conditioner are among the most toxic beauty products. These products are more likely to contain harmful ingredients such as aluminium, triclosan, sulphates, and parabens.