Why Is Material Selection Important in Personal Care Products? Bio-Based, Natural, and Recyclable Materials

Bio-based, natural-source, eco-friendly, and recyclable personal care products are becoming the focus not only of sustainability trends but also of material science and human health research.

A scientific approach does not establish a simple equation like “plastic is bad, natural is good.” The impact of a material on human health and the environment depends on many variables, from its chemical structure to its production method, from its duration of use to its wear and tear, and from its recyclability to the waste it creates at the end of its life cycle.

In this article, we will examine why it is important to know which materials the products that come into contact with our bodies are made of, in light of scientific data. We will also discuss why the choice of materials for items that are an inseparable part of our daily lives—the clothes that wrap our bodies, products we apply directly to our skin, brushes that touch our hair and scalp, combs, toothbrushes, shower gels, etc.—is becoming increasingly important.

Plastic Is Not a Single Substance: Over 13,000 Chemicals Are Associated with Plastics

When we say “plastic,” we are not actually talking about a single chemical substance.

According to the United Nations Environment Programme (UNEP) 2023 report titled "Chemicals in Plastics," more than 13,000 chemical substances are known to be used in plastic production or found within plastic materials.

More importantly, scientific evidence shows that out of approximately 7,000 substances for which hazard data exists, more than 3,200 exhibit at least one hazardous property. The areas where these chemicals are used include not only packaging but also textiles, electronics, medical devices, household products, and personal care products.

Can Chemicals in Plastic Products Really Have a Biological Effect?

There is remarkable data from laboratory studies on this subject.

In a 2019 study published in the journal *Environmental Science & Technology*, extracts obtained from 34 plastic consumer products representing eight different polymer types were analyzed chemically and toxicologically.

The study found that in the samples:

• • • 74% contained chemicals that affected at least one of the biological tests studied,
    • 62% showed baseline toxicity,
    • 41% showed oxidative stress activity,
    • 32% showed cell toxicity,
    • 12% showed estrogenic activity,
    • 27% showed antiandrogenic activity.

Researchers also identified 1,411 chemical features in the analyses.

There is an important scientific boundary here: these are *in vitro*, meaning biological test results in a laboratory environment. It does not show that the same effects will occur in a human who touches a plastic product.

However, it is one of the important experimental data points showing that plastics should not be considered chemically homogeneous and completely inert materials.

The Material Reality in Our Daily Care Routine: Scientific Findings

This issue is no longer limited to packaging or marine pollution. In a 2026 study conducted in Turkey, 79 shampoos, shower gels, peeling gels, and toothpastes were analyzed for their microplastic content.

In the distribution of detected fibers, shower gels accounted for 46%, peeling gels for 40%, and shampoos for 14%. No microplastics were detected in the toothpastes examined, and the researchers specifically emphasized that there is still a need for standardization of methods.

Data analyses based on PubMed Central PMC research are shared specifically for toothbrushes, hairbrushes/combs, and metal hair accessories on a product/material basis:

• • Toothbrush – microplastic release: A 2025 experimental study reported that in toothbrushing simulations, 63% of the microplastics released were smaller than 100 µm, and among the identified polymers, polypropylene had the highest share at 22%. The researchers calculated that an average of at least 2.33 million microplastic particles could be released from a toothbrush per person annually. However, the study did not demonstrate that the level of exposure examined posed a direct health risk.
    
    
  • Metal in combs and hairbrushes – nickel: In a study evaluating 226 patients suspected of having scalp contact dermatitis, the positive patch test rate was 23.8% for nickel and 21% for cobalt. The researchers note that sources of nickel exposure on the scalp include combs, hairbrushes, metal-bristled brushes, and hair accessories. These rates represent a selected patient group tested for suspected dermatitis, not the general population.
    
    
  • Hair accessories – direct nickel release: In a study cited in the same literature review, it was reported that 19.3% of adult hair clips and 79.4% of children's hair clips released nickel above the test threshold. This data is a concrete example of why the material and coating quality of metal parts that come into contact with skin and scalp can be important.
    
    
  • Hairbrush handles – rubber components: In the same 226-person study, an 11.6% positive patch test was found for "carba mix," which is associated with accelerators used in rubber production. The study includes hairbrush handles among potential contact sources. This shows that the “plastic/metal/natural” distinction is not enough on its own; coatings, rubber, and auxiliary materials are also significant.
    
    

Shampoo and shower products – microplastic: The 2026 study published in Turkey examined 79 shampoos, shower gels, peeling gels, and toothpastes. In the distribution of detected microplastic fibers, shower gels had a 46% share, peeling gels 40%, and shampoos 14%; no microplastics were detected in the toothpastes examined. Researchers specifically state that methods still need standardization.

So Should We Be Concerned About Plastic Products That Touch Our Skin?

Touching a sturdy, high-quality plastic product does not mean that all the chemicals within the product are passing from our skin into our bodies.

Skin is a powerful biological barrier, and true dermal exposure depends on many variables such as the molecular properties, concentration, contact duration, skin integrity, and the manner in which the product is used.

Notably, the 2026 dermatology review, which examines the health and environmental effects of plastics in the personal care sector, points out that microplastics, nanoplastics, plastic-related chemicals, and environmental pollution caused by personal care products must be evaluated together.

Why Are Natural and Bio-based Materials Gaining Importance?

Consumer trends are not the only thing behind the rise of bio-based materials.

The quest to reduce the environmental impacts of fossil resource consumption, plastic waste, and the linear production model is accelerating the development of materials produced from renewable raw materials.

Bio-based materials can be produced entirely or partially from renewable sources such as:

• • cellulose,
  • wood,
  • sugarcane,
  • starch,
  • various plant-based raw materials
    
    

However, three concepts must be distinguished here:
Bio-based ≠ biodegradable.
Biodegradable ≠ compostable.
Natural ≠ automatically safer.

To understand whether a material is truly eco-friendly, one must look not only at its raw material but also at the production energy, water and land usage, transportation, durability, recyclability, and how it is processed at the end of its life cycle.

 

Do Eco-Friendly Products Really Make a Difference? What Do Life Cycle Assessments Say?

Scientific life cycle studies indicate that some bio-based and naturally sourced materials can offer advantages over fossil-based alternatives in specific environmental impact categories, depending on raw materials and production conditions.

• • 63% lower carbon impact: In a 2024 life cycle study, the global warming potential of the second-generation bio-based PBAT examined was calculated to be 63% lower than the fossil-based PBAT compared in the study. This result is specific to the production scenario examined and cannot be generalized to all bio-based materials.
    
    
  • 241–316 million tons of CO₂-equivalent potential: A modeling study calculated that if technically substitutable fossil-based plastics were replaced with bio-based alternatives, there is a potential for annual emission reductions of approximately 241–316 million tons of CO₂-equivalent. This figure does not represent an achieved reduction, but rather a scenario based on specific assumptions.
    
    
  • Potential for reduced fossil resource use: Life cycle studies show that under appropriate raw material and production conditions, some bio-based materials can contribute to reducing fossil resource consumption and greenhouse gas emissions.
    
    

These findings do not mean that bio-based or natural materials are more eco-friendly under all circumstances. Environmental performance can vary based on the source of the raw material, the production method, energy and water usage, the durability of the product, its lifespan, and post-use recycling or disposal processes.

Why Is Recyclability Important?

The environmental impact of a personal care product does not end when we finish using it.

When a product is thrown in the trash, it becomes important whether the different materials it contains can be separated, whether they can actually be recycled in local systems, and how much of the product turns into waste.

Therefore, in sustainable product design, it is important not only to use recycled materials but also to:

• • use less material,
    
    
  • extend product life,
    
    
  • design replaceable parts,
    
    
  • facilitate the separation of different materials,
    
    
  • reintegrate recycled raw materials into the system,
    
    
  • plan for the end of the product's life during the design stage.

This is the core message of the scientific life cycle approach: just as important as searching for the most sustainable material is designing a product that can be used for longer with fewer resources.

Everything That Touches Our Body Has a Material Story

Science does not tell us that all plastics are harmful. It does not tell us that all metals are dangerous. And it certainly does not tell us that every product labeled "natural" is automatically better for human health or the planet.

However, we now have data that is hard to ignore.

Life cycle studies show that even personal care products serving the same function can have vastly different environmental footprints depending on the materials used and the design.

Bio-based raw materials, recycled materials, durable product designs, and more transparent material information are, therefore, not just trends. They are parts of a broader transformation toward evaluating personal care collectively from the perspectives of human health, materials science, and environmental sustainability.

Because when we choose products that touch our bodies, we are not just making a choice for ourselves. Each material choice is also a decision regarding the type of production and consumption cycle we support, as well as the experiential habits we leave to future generations.