Could Your Laundry Routine Be Causing Sensitive Skin?

Laundry Products and Skin Allergies: What Does the Science Say?

Laundry detergents are essential for clean clothes, but their chemical ingredients can sometimes spell trouble for sensitive skin. Recent scientific research shows how detergents might affect conditions such as contact dermatitis (allergic or irritant rashes from contact) and atopic dermatitis (eczema).

In this blog, we delve into up-to-date studies on laundry detergents and skin health, examining the roles of surfactants, fragrances, preservatives, and enzymes. We also explore how modern formulations interact with the skin’s barrier and immune system.

Surfactants: Cleaning Agents That Can Disrupt the Skin Barrier

Surfactants are the core cleaning agents in detergents – they lift away dirt and oils. However, these molecules (especially strong anionic surfactants like sodium lauryl sulphate or linear alkylbenzene sulfonates) can also strip natural oils from the skin and disturb cellular junctions. Research has shown that surfactants can compromise the skin’s protective barrier even at low concentrations. In laboratory models, common detergent surfactants such as sodium lauryl sulfate (SLS) and SDBS (sodium dodecylbenzene sulfonate) reduced skin cell barrier integrity – by increasing permeability to substances​, which allows pollutants and allergens to enter the blood stream (source).

These changes were observed even at non-toxic doses, indicating that routine exposure to dilute detergent residue might still subtly affect skin barrier function (source).  This risk is particularly high for babies and young children and is thought to be related to the explosion of allergic conditions since WW2.

Surfactants also altered proteins like claudin-1 and occludin that seal our skin cells together, essentially loosening the barrier​ (source)

For people with eczema (atopic dermatitis), this effect can be pronounced. Studies dating back decades show that atopic dermatitis patients are extra susceptible to surfactant irritation – they experience more transepidermal water loss (dryness) and inflammation with SLS exposure than people without eczema​ (source).

In fact, using SLS on skin is a common way for researchers to induce a mild irritant dermatitis in experiments. This surfactant-induced barrier damage can set the stage for allergens to penetrate more deeply. One classic study found that applying 1% SLS to skin allowed nickel and chromium (normally weak allergens) to trigger eczema-like reactions in guinea pigs, whereas without SLS these metals caused little to no reaction (source).

By increasing skin permeability and causing inflammation, surfactants lower the threshold for allergic responses to other substances​ (source).

Thus, while surfactants are effective cleaners, they can also be irritants that exacerbate conditions like eczema or even facilitate new allergies.

It’s not just irritation – in some cases surfactants themselves can be true allergens. Cocamidopropyl betaine (CAPB), a commonly used “mild” detergent ingredient (often in shampoos and some laundry products), was named Allergen of the Year in 2004 by the American Contact Dermatitis Society due to its propensity to cause allergic contact dermatitis in susceptible individuals​  (source).  Patch test studies found up to 7% of people tested showed an allergic reaction to CAPB​ (source).

Even components designed to be gentle can occasionally induce immune-mediated skin reactions in some users. Overall, current evidence indicates that surfactants can affect the skin on multiple levels – provoking immediate irritation and dryness, weakening the barrier (which can lead to increased allergen penetration), and in rare cases causing allergic sensitisation themselves.

Fragrances and Preservatives: Common Allergenic Culprits in Detergents

Fragrance chemicals and preservative additives are among the top offenders for allergic skin reactions, and they are routinely present in many laundry products. Fragrances are a frequent cause of allergic contact dermatitis across all household products and there have been documented cases of fragrance-induced skin allergies from laundered clothing​ (source).  Researchers suggest that residues of fragrance left on fabrics can lead to rashes in people who have become sensitised (allergic) to those scent molecules​ (source 1) (source 2).

Preservatives are another concern. To prevent microbial growth in liquid detergents, manufacturers often include biocides like isothiazolinones (for example, methylisothiazolinone (MI), methylchloroisothiazolinone (MCI), or benzisothiazolinone). These preservatives are well-known causes of allergic contact dermatitis. In fact, MI was named Allergen of the Year in 2013 due to a spike in contact allergy cases from its use in cosmetics and cleaners. Laundry detergents, being rinse-off products, contain isothiazolinones in low levels – yet cases of allergy have been reported. One published case involved a 7-year-old girl who developed allergic dermatitis from the MI in her laundry detergent​ (source).  A 2023 review noted that laundry detergents are the confirmed cause of allergic contact dermatitis in fewer than 1% of cases overall​(source 1) (source 2).

For sensitive individuals, fragrances and preservatives in detergents remain suspect and should be avoided. Common allergenic ingredients in detergents include fragrance compounds (like limonene or linalool in scent blends) and isothiazolinone preservatives (source).  If someone with eczema or contact dermatitis notices flare-ups, dermatologists often first recommend switching to a fragrance-free, dye-free detergent to eliminate a couple of these variables. Regulatory steps have been taken to help consumers identify these allergens: the European Commission now requires that 26 known fragrance allergens be disclosed on labels if they exceed certain trace amounts in detergents​ (source).

This kind of transparency allows allergic individuals to avoid specific triggers. In summary, fragrances and preservative biocides in laundry products can exacerbate skin allergies and eczema in a subset of people – and while most users won’t react, those with known sensitivities should be cautious about these hidden ingredients.

Enzymes in Modern Detergents: Powerful Cleaners with Allergenic Potential

Many “modern” laundry detergents – especially biological detergents – contain added enzymes to break down stains. These enzymes (like proteases, lipases, and amylases) digest protein, fat, and starch residues on fabric, making detergents more effective at cleaning. However, because enzymes are proteins themselves, they have the potential to act as allergens. A protein that can chew through biological material is also capable of interacting with the skin’s proteins and immune cells and weakening the outer skin barrier. So, are detergent enzymes a problem for skin? Research is actively investigating this question.

When enzyme detergents were first introduced in the 1960s, there were reports of factory workers developing allergies (especially respiratory allergies like asthma) from inhaling airborne enzyme dust. Manufacturers responded by encapsulating enzymes and improving formulations to minimize airborne exposure. In everyday consumer use, enzyme molecules in detergent are largely rinsed out and thus contact with skin is limited. Nonetheless, scientists have raised concerns that constant low-grade exposure to enzyme residues on clothing might contribute to skin barrier impairment or sensitisation over time​  (source).

Recent laboratory studies lend some weight to this concern. In a 2022 study, researchers explored how laundry detergent enzymes affect skin in a mouse model. They found that exposing mouse skin (especially neonatal skin) to microbial protease enzymes caused visible skin damage and triggered the release of key “alarmin” cytokines (specifically IL-33 and TSLP) from the skin tissue​ (source).

These cytokines are signals that drive allergic inflammation. When mice were repeatedly exposed to a combination of detergent and a test allergen, they developed increased transepidermal water loss (indicating a leaky skin barrier) and produced allergen-specific IgE antibodies – a hallmark of allergic sensitisation​ (source).

In fact, the detergent-exposed mice showed a stronger allergic immune response and even signs of inflammation in organs like the oesophagus, after allergen challenge (source).

The researchers concluded that laundry detergent exposure “may be an important factor that impairs the skin barrier and leads to allergen sensitization in early life,” potentially contributing to the rise of allergic diseases​ (source).

In other words, enzyme-containing detergents might are likely to damage the developing skin barrier and provoking immune responses in babies and infants.

It’s important to note that this was an animal study, and mice were exposed in ways that might not perfectly mimic human laundry routines. Still, the results align with the broader “epithelial barrier hypothesis” of allergy – the idea that damage to barrier tissues (skin, gut lining, etc.) is a key driver of allergic sensitization. Separately, a 2024 laboratory study in the journal Allergy demonstrated that even highly diluted household detergents can harm skin tissue. In that study, human skin models treated with very low concentrations of detergent showed reduced expression of tight junction proteins (crucial components of the skin barrier) and increased inflammatory markers like interleukin-1β and IL-6​  (source 1) (source 2).  The authors found that both whole detergent and pure SLS (its main surfactant) caused significant barrier breakdown in ex vivo human skin, leading them to warn that daily detergent exposure may contribute to atopic disease by disrupting the epidermal barrier ​(source).

In summary, enzymes in laundry detergents raise concerns about skin barrier effects and allergic sensitisation.

Impact on Skin Barrier Function and Immune Responses

One of the recurring themes in recent allergy research is the importance of the skin’s barrier function. The skin barrier (primarily the outer epidermis and its tight junctions between cells) is our first line of defence. If this barrier is disrupted, it not only leads to dryness and irritation but can also kickstart immune reactions. Modern formulations of detergents have the potential to impact this skin barrier–immune system interplay in significant ways.

Studies have demonstrated that detergents can directly damage the skin’s structural integrity. For instance, the 2024 study by Rinaldi et al. used techniques like electric impedance and gene expression analysis to show that even a few hours of detergent exposure can downregulate genes for skin structural proteins (like those involved in tight junctions and cell adhesion) while upregulating pro-inflammatory genes (source 1) (source 2).

In practical terms, detergents were seen to make skin tissues more “leaky” and inflamed. The skin’s immune sensors respond to such stress by releasing alarm signals. Laboratory and animal research consistently find increases in cytokines such as IL-1β, IL-6, IL-33, and TSLP in detergent-exposed skin​ (source 1) (source 2).

IL-33 and TSLP, in particular, are key drivers that skew the immune system toward allergic inflammation (they activate type 2 immunity, including IgE production and eosinophils). This suggests a mechanism by which daily exposure to harsh cleansers might subtly promote conditions like atopic dermatitis, asthma, or even food allergies – a damaged skin barrier could allow allergens to penetrate and sensitise the immune system.

A 2023 review in Current Allergy and Asthma Reports summarized this concept, noting that detergents and related chemicals can initiate epithelial barrier dysfunction and subsequent allergic inflammation​ (source). The authors pointed out that rising rates of atopic disorders in industrialized countries could be partly explained by environmental factors that damage the epithelium (skin and mucosa). Detergents are highlighted as a possible modifiable risk factor for the development or worsening of allergies (source).

In summary, while genetics set the stage for eczema or allergies, environmental exposures like frequent washing with strong detergents could push someone over the threshold by repeatedly disturbing the skin barrier and priming the immune system.

For infants (with delicate, developing skin) and for adults with existing atopic tendencies, the cumulative impact of detergents and soaps is an area of concern. The mouse model research suggests early-life detergent exposure had systemic immune effects (source) lending weight to the advice many paediatric dermatologists give: use gentle cleansers and detergents for babies to help protect their skin barrier.

Finally, it’s worth noting that the skin microbiome (the ecosystem of microbes on our skin) is also part of the equation. A balanced skin microbiome helps educate and regulate our immune responses. Some detergent ingredients could upset this microbiome balance by killing beneficial bacteria or favouring the overgrowth of harmful ones. If a detergent leaves behind residues of harsh antimicrobials (like certain preservatives or antiseptic additives), it might reduce the diversity of skin flora. Since loss of microbial diversity and dominance by Staphylococcus aureus are known factors in atopic dermatitis​ (source).

Choosing products that are microbiome-gentle is part of maintaining healthy skin. This is an emerging research frontier – some companies now test detergents for their microbiome impact, aiming to prevent collateral damage to our skin’s “good bugs.” All these findings underscore that laundry products are not biologically inert; they can interact with our skin’s barrier and immune system in subtle ways.

Tips for Choosing and Using Detergents for Sensitive Skin

What practical steps can individuals take if they have sensitive skin, eczema, or allergies? Dermatologists and allergy experts generally advise a precautionary approach: minimize exposure to known irritants and allergens in your laundry routine. Here is a brief research-backed list of recommendations:

• Go for gentle, hypoallergenic detergents: Choose products that are fragrance-free and dye-free. The US National Eczema Association (NEA) recommends using liquid detergents without added perfumes or colours, as liquids tend to leave less residue than powders.
• Rinse thoroughly: Residue is the enemy for sensitive skin. Use an extra rinse cycle if possible to ensure minimal detergent remains in fabrics.  Studies indicate that thorough rinsing can reduce detergent allergen levels to below thresholds that trigger reactions. Avoid overloading the washing machine or using excessive detergent, as this can leave soap trapped in clothes.
• Avoid strong fabric softeners and additives: Fabric softeners and scent boosters often contain fragrances and quaternary ammonium compounds that can stick to clothes and irritate skin. If you need a softener, opt for an organic fragrance-free version. Similarly, be cautious with new antibacterial or sanitising laundry additives – there have been reports of these causing rashes in eczema-prone users, most likely due to harsh disinfectant chemicals.
• Use “non-biological” detergents: If you suspect enzymes are aggravating your skin (for example, if you’ve ruled out fragrance and other allergens but still have issues), you could experiment with a non-biological detergent (one without enzymes).
• Pre-wash new fabrics and manage contact: New clothing and linens often have manufacturing chemicals (sizing, dyes, finishing resins) that can irritate skin. Always wash new clothes before wearing to remove these residues.
• If someone in the household has eczema, it may help to wash their clothes separately and do an empty rinse cycle in between loads. This prevents cross-contamination of allergens.
• Ensure your washing machine is kept clean – biofilm and detergent buildup in the drum could redeposit irritants onto clothing.

 Are laundry products safe?

Laundry products are an essential part of modern life.  Scientific research in the past five years has improved our understanding of the impact conventional detergents have on our health. We now know that certain detergent ingredients – harsh surfactants, fragrance allergens, potent preservatives, and enzymes – can interact with the skin’s barrier and immune system in ways that may trigger or worsen skin problems.

Surfactants can cause barrier leakage and inflammation; fragrances and preservatives can spark true allergic reactions; enzymes might contribute to barrier breakdown and sensitisation under some conditions.

In infants, the skin barrier is still developing, making it more susceptible to irritants. Research indicates that even trace amounts of laundry detergents left on fabrics can disrupt the epithelial barrier function, increasing the risk of skin irritation and allergic reactions. Pregnant women may also experience heightened skin sensitivity due to hormonal changes, rendering them more prone to irritant contact dermatitis when exposed to such chemicals. ​

Sources:

1. Christou et al., Health Science Reports (2024) – Evaluating sensitive-skin detergents on atopic dermatitis patients​  pmc.ncbi.nlm.nih.gov.
2. Patel et al., Cutis (2023) – Review on allergic contact dermatitis from laundry products (noting <1% incidence)​ pmc.ncbi.nlm.nih.gov.
3. Tanzer et al., PLoS ONE (2022) – Mouse model study linking detergent exposure to barrier damage and allergy development​ journals.plos.org.
4. ​Rinaldi et al., Allergy (2024) – Detergents disrupt skin barrier in mouse and human skin experiments​ ncbi.nlm.nih.gov.
5. Doyle et al., Curr Allergy Asthma Rep (2023) – “Allergies come clean” review on detergents causing epithelial barrier dysfunction​ pmc.ncbi.nlm.nih.gov.
6. Healthline (2021) – Eczema and laundry tips (fragrance-free products, double rinsing, etc.)​ healthline.com
7. Medical News Today (2024) – NEA recommendations for eczema-friendly laundry detergents​ medicalnewstoday.com
8. Basketter et al., Contact Dermatitis (2018) – Study on fragrance residues in fabric not causing reactions in sensitized individuals pmc.ncbi.nlm.nih.gov.
9. Trompette et al., Science Direct (2023) – Skin barrier immunology from early life to adulthood. https://www.sciencedirect.com/science/article/pii/S1933021923000132