Your skin is in safe hands: How Lush test products for safety and efficacy

Written by Milly Ahlquist                                                                                       

Updated: April 2026

Don’t be fooled by the hippy vibe you might get from Lush; there’s serious science behind our skincare. From testing sunscreens on the slopes of Mount Kilimanjaro to funding cutting-edge, non-animal new approach methodologies (NA NAMs), our products have always been tried, tested and trusted by humans. Today, Lush product assessments embody animal-free toxicology assessments, real-life, real-time tester feedback and human cell culture data to provide you with products that work with robust safety data behind them. Heck, we’ve even got a clinical study or two under our belts.

The Lush Safety Standard

• 100% Animal-Free: We rely on human cell cultures, 3D skin models (NA NAMs) and human-relevant scientific literature instead of animal testing data.
• Human-Centric: A panel of 450+ diverse volunteers ensures efficacy across skin tones and hair types.
• Clinical Rigor: We’ve invested £3.8m in safety research so far, and conducted independent clinical trials on products like Dream Cream.
• Formulation Expertise: Led by toxicologists and co-founders with 40+ years of experience.

We’ve always known that animal testing is unethical and unreliable for predicting safety in people. We just had to wait for the science to catch up  – and what a journey that’s been.

Lush’s History of Human Cosmetics Testing: Tested by People Right from the Beginning

When Lush was but a twinkle in the eye of our very first venture, Constantine & Weir, the C&W team were united by their passion for innovation, for natural materials and for testing on people, not animals. The townsfolk of Poole were our happy volunteers. Friends, family, the neighbour who watered the plants that time… All were treated to foot masks, henna treatments, lotions and potions for the very reasonable price of some honest feedback. During our Cosmetics To Go era, Lush Director Karl Bygrave applied sunscreens to his skin under a UV lamp in 29 High Street. Lush Co-Founder and Product Inventor Rowena Bird trialled her Africa Companion range on the slopes of Mount Kilimanjaro. And who in Poole didn’t have their hair hennaed by Mark Constantine at some point in the ‘80s? (Hit us up; he’ll probably still do it.)

After Lush was founded in 1995 and the business expanded, so too did our need for more testers. Today we have over 450 independent testers on our books, who tell us about their skin and hair and are sent products according to their needs. In recent years, our in-house Quality Team have been working on building up inclusivity and representation on the tester panel, to ensure the full spectrum of skin colour and hair texture are represented. This enables testers to receive products formulated with their needs in mind and gives our inventors access to honest, authentic opinions about what works for our customers. 

Tester feedback is also an integral part of Lush’s overall safety assessment work, which flows through multiple teams and our experienced external Product Safety Advisors. The Quality Team works with a leading microbiological lab to assess a product’s in-use stability and performance, which enables us to accurately determine shelf life based on how the product will realistically be used and stored. Having complete control over every aspect of formulation and manufacturing of our products means we can deliver products that are safe, fresh, effective and offer a safe but not sterile alternative to your standard, long-shelf life beauty product.  “We invest a lot of time and work into doing all of the monitoring and it's very much monitoring these products in real life, in real time and on real people,” explains Quality Lead Jet Shears, who celebrated her 25th anniversary with the business this year. You can read more about our work with live cultures here. 

1987: The Assisi Project

As early as 1987, Constantine & Weir were funding work into NA NAMs with their Assisi Project work. Not only were the team resolute in their belief that animal testing was cruel, they were also convinced it was not the best way to keep their customers safe.  Never ones to take the easy road, the project had two main goals: to survey existing knowledge on the use of alternative methods, and to select from these the most likely candidates for a test series that would be applicable to all the products they made

But it was personal too. Many of the Co-Founders had become parents and couldn’t find any products on the High Street that they were happy to use on their own children. Surely other parents felt the same? The big advantage of having their own cosmetics company, of course, was that they could take matters into their own hands.

Introduced in 1988, Baby Revels was a range of natural-based skincare products developed by Lush Co-Founder Helen Ambrosen, and thoroughly appreciated by her young sons (and other parents). Five-month-old Robin even joined his mum on film to demo the products!

But it wasn’t just the quality of the products but also the quality of the testing, of course. Knowing that babies’ skin is particularly sensitive, Helen and her fellow Co-Founder Elizabeth Weir worked with experts in their field to develop the Assisi Test: an alternative to a particularly cruel irritancy test that involved the dripping of ingredients into rabbits’ eyes. It was the first irritancy assessment using milk and yeast-based serums rather than animal-derived materials  – meaning parents could use Lush’s cruelty-free baby range with complete confidence. 

Out of the Assisi Project came a dossier of thoroughly investigated alternatives to animal tests presented to the European Commission for consideration. To great acclaim, Cosmetics To Go also laid down the principles that form the Fighting Animal Testing policy Lush upholds today: not to buy from (and therefore invest money in) any raw ingredients suppliers that conduct animal testing, even if we don’t use that specific material. 

Glove Juice Analysis 2006-2008

From early in our inventing days, the Lush Co-Founders have been interested in how products (especially preserved ones) interact with the microbiome: a protective ecosystem of bacteria, yeasts, fungi and more that live on the skin. Formulating with the microbiome in mind has also been a backbone of the self-preserving work they have undertaken to provide an alternative to preserved, long shelf-life skincare.

Back in 2006, we commissioned a Canadian expert microbiologist to develop a study that would examine how the naturally occurring, live microbiota in our freshest, self-preserving products might affect the microbiome on the skin of 75 volunteers. The results told us that the microbial interplay between our freshest products and the customer’s skin is short-term and not harmful. We also learned that a preserved product lowered the levels of a particular common beneficial skin bacterium on the participants’ hands more, and for a longer period of time, than the other products. While these results were not statistically significant, it was another indication to us that formulating without preservatives wherever we can is worth the time and effort. 

Advanced Toxicology: How We Test with Human Cell Cultures

Our partnership with the UK’s first completely animal-free test house goes way back. In 2013, XCellR8 won £25,000 at the Lush Prize (our global prize fund that supports initiatives to end or replace animal testing) for providing training in ethically sound and scientifically advanced human cell culture research technologies. The science had finally caught up with what Lush has always believed; we were entering a new era of human-relevant testing.

A partnership was struck, and for over a decade now, we have been working together to diligently build up a database of ingredient safety information based on human biology-relevant models. Innovative tests on human skin cell models (not tests containing ‘cruelty-free’ animal components derived from the meat industry) have given us new and more accurate insights into cosmetic ingredients on humans. Not only is it more ethical, but using human cells to test human exposures is simply better science than relying on historic animal data.

Combining the data generated with XCellR8 with extensive human-study literature reviews, our in-house Toxicology Team uses a tiered approach to assess ingredients and products for the following endpoints:

1. Genotoxicity: the ability of a test item to damage the genetic material of cells (DNA). These changes to DNA can potentially lead to cancers. 
2. Skin sensitisation: the ability of chemicals to elicit an allergic response in susceptible individuals (this is not the same as reacting to a material you have an established allergy to). 
3. Systemic toxicity: the effects that occur at distance from the site of application after long-term exposure. 

From sunscreens to essential oils, we have animal-free, human-relevant data on over 1,000 ingredients. This is ready to be used by our inventors and in-house perfumers as they formulate safe and effective products. 

2021: 3D Skin Barrier Test

In 2021, as part of our research into the development of hair dyes that meet our stringent internal safety standards, we worked with XCellR8 to develop a more sophisticated genotoxicity test. The standard 2D genotoxicity method involves adding test materials to incubated human white blood cells and making sure they do not induce oxidative stress. The upgraded 3D Skin Barrier model, however, incorporates a reconstructed epidermis, allowing scientists to also measure how much of a substance actually penetrates the skin to reach the cells below. Lead Lush Toxicologist Dr Chloé Raffalli explains, 

“The advantage of this technique, in comparison with the standard genotoxic assays in 2D, is that it takes into account the protection of the skin barrier as well as the metabolism of the skin enzymes. We are also able to test our ingredients and products in more realistic conditions.” 

The first ingredient we tested was the natural red henna grown in Iran, which was found to not compromise skin cell health after a 48-hour application. Having comprehensively investigated the poor safety record of high street hair dyes in True Colours: Hair Dyeing For The Curious & The Cautious, it bolstered our confidence in henna and meant we could give clear reassurance to our customers. It may have only been around for a few years, but this upgraded genotoxicity test has already proven worth its salt, enabling us to undertake ever more sensitive and accurate testing in the name of customer safety. You can read about how to dye your hair more safely with or without synthetic dyes here.

2023: Our First Clinical Testing

For decades our customers have been telling us that Dream Cream body lotion has been a family staple, especially when it comes to coping with sensitive and eczema-prone skin. And so, in 2023, we commissioned two independent studies supervised by a dermatologist comparing the effects of our preserved and self-preserving Dream Cream in children with eczema over the age of three. It was a satisfying itch to scratch, with the results showing an improvement in redness, dryness, irritation  – even sleep! Soothed skin. Satisfied parents.  

So which to pick? The results were close but our self-preserving Dream Cream just edged it, meaning you can now find a product suitable for the most sensitive of skin without added synthetic preservatives.

Read more on our Dream Cream testing results.

2023 to Today: Skin irritancy

Fed up of competitors and influencers claiming that fragrance and physical exfoliators damage the skin whilst promoting high-strength ingredients like retinol, in 2023, we decided to put our skincare through a series of irritancy tests with XCellR8. It was important to us that these tests assessed the potential irritancy of the product on the skin as we ask the customer to use it. 

“The standard Xtra Mild skincare test measures a product's irritancy by assessing cell viability on human tissues after a 48 hour exposure. This was valid for products left on the skin like moisturisers, but not for products like cleansers that are intended to be washed off,” explains Lead Lush Toxicologist Chloe Raffali. “For this reason, we tested our core skincare range under both standard conditions (48-hour exposure on skin tissue) and under realistic conditions (how we ask the customer to use them). This has enabled us to get accurate data on the effects of wash-off products like cleansers.”

The results were vindicating: almost every tested Lush skincare product was completely non-irritating or very mild to human skin in realistic use conditions. In fact, it was only our Bright & Beautiful vitamin C facial scrub that did not fall within these categories, being classed as mild to moderate when used as a scrub. As our most exfoliating product, this was unsurprising. “When the products were tested in the way they are intended to be used, there was very little difference between them,” explains Dr Raffali. “Nearly all were found to be non-irritating or very mild, which is a positive outcome. No products designed to be left on the skin were irritating in standard 48-hour exposure.”

“The results we’ve had tell us what we already knew,” Helen explains, “that we formulate carefully in a way that’s sensitive to the skin. They also tell us that blanket statements about avoiding perfume, essential oils or physical exfoliants don’t ring true - it comes down to expertise in formulation and knowledge of your ingredients.”

Developing Diverse and Inclusive Skin Cell Tissue Models

We passionately believe that not only should science be animal-free but that it should be representative too. In 2025, when we learned that standard cell culture tests use tissues donated from a male White donor, we commissioned work with XCellR8  to develop more inclusive cell models using tissues donated from Black and Asian donors of different sexes. Our aim is to see what (if any) differences there are between irritation results generated by these different skin models. Building up this picture will enable us to better serve our customers of different skin tones. This exciting work is in development and reflects our commitment to making a product for every need. 

They say don’t work with animals or children… Well, we’ve never worked with animals but the Founders’ children could always be relied on to deliver some honest feedback. Decades later, many of them are on the receiving end of their own children’s constructive criticism today. People remain at the core of our testing process, but as the science has evolved so too has our access to tests that show our products are ethical, efficacious and safe.

“From buying cruelty-free ingredients that adhere to our non-animal testing policy to then assessing their safety and their effects on the skin in a completely animal-free way, we are leading the way in championing truly cruelty-free products within the personal care industry,” explains Helen. “We’ve invested £3.8m in this work so far, because we were not content to use historical animal data or bovine serums and we don’t think they keep our customers safe. I realised recently that we offer the first truly cruelty-free products on the High Street, when you take into account the work done from source to skin.” 

Although progress in this area has been significant, there is still work to be done to make the use of truly cruelty-free methodologies widespread. “35 years ago, we were not content to use bovine serums made from calf’s blood,” explains Lush Director Karl Bygrave. “But today, many NA NAMs still use these materials as standard because their use is not really considered. But when you’re working with vegetarians and vegans, they think about the whole process and this is the stuff that matters. So, the need to educate is still present as not all scientists consider the components such as the bovine serum used in their test methods.”

For Lush Co-Founders like Helen, it’s integral to their ambition to make products that will care for you for life. “You should never have an uneasy feeling if you’ve used a product from Lush,” says Mark. “We are interested in long-term care, not cheap, short-term results. That’s why we are offering products that consider the health of your skin beyond its appearance.”