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Category: Manufacturing Guide

Microbiological Testing for Cosmetics

Posted on by Stephanie Varchione

Microbiological testing is one part of understanding how a cosmetic or personal care product performs as it moves through development and towards commercial manufacturing.

Depending on the product, testing may include bacterial, yeast and mould testing and preservative efficacy testing. These tests provide information that can help the development and quality teams assess the formulation and determine whether further work may be required.

For brands, the important thing is understanding what testing is relevant to the individual product and allowing for it within the development process.

Why Is Microbiological Testing Important?

Cosmetic products can be exposed to microorganisms through ingredients, manufacturing, packaging and use.

The microbiological considerations will vary depending on the formulation. Water-containing products such as creams, lotions, cleansers and serums may require different considerations from products with a lower microbiological risk.

Testing gives the development and quality teams information about the microbiological condition of the product and, where relevant, how its preservative system performs.

The appropriate testing program should be considered for the individual formulation rather than applying the same approach to every cosmetic product.

What Types of Microbiological Testing May Be Used?

Two common areas of microbiological testing during cosmetic product development are:

  • Bacterial, yeast and mould testing
  • Preservative efficacy testing

The testing required will depend on the formulation, intended use and other product requirements.

Bacterial, Yeast and Mould Testing

Bacterial, yeast and mould testing provides information about the microorganisms present in a product sample at the time of testing.

Results can be assessed against the specifications or requirements that apply to the product.

For brands, this testing forms part of the wider quality picture alongside formulation development, stability testing and manufacturing controls.

The exact method and acceptance criteria will depend on the product.

Preservative Efficacy Testing

Preservative efficacy testing, sometimes referred to as PET or challenge testing, is used to assess how the preservative system within a formulation performs when challenged with specified microorganisms.

The test is carried out over a defined period, with results assessed at scheduled intervals.

If the formulation does not meet the applicable acceptance criteria, further development work may be required before the product progresses.

This could involve reviewing the formulation and preservative system before testing again.

Does Every Cosmetic Product Need the Same Testing?

No. The microbiological risk of a product depends on factors such as its formulation, how it will be used and the environment in which microorganisms may be able to grow.

A water-based cream, for example, may have different requirements from a product that presents a lower microbiological risk.

The testing pathway should therefore be developed around the individual product.

For brands that are new to manufacturing, this is an important distinction. A standard list of tests should not simply be applied to every formulation without considering whether those tests are relevant.

How Does Preservative Efficacy Testing Fit Into Product Development?

Preservative efficacy testing is generally considered once the formulation has reached an appropriate stage of development.

The purpose is to provide information about the performance of the preservative system within the finished formulation.

If the results indicate that the formulation needs further work, the development team can review the product before it moves further through the manufacturing process.

Allowing time for this within the development plan is important, particularly if further formulation work and repeat testing are required.

What About Microbiological Limits?

Cosmetic microbiological standards can set limits for the number of microorganisms present in finished products and may also include requirements relating to specified microorganisms.

The requirements can vary depending on factors such as the product category and intended area of use.

Rather than expecting brands to determine these limits themselves, the appropriate testing method and specifications should be established based on the individual product and its requirements.

Recognised Microbiological Testing Methods

Cosmetic microbiological testing may use recognised methods and standards depending on the product and testing requirements.

These can include standards relating to:

  • Evaluation of preservative efficacy
  • Microbiological limits
  • Enumeration of bacteria, yeast and mould
  • Detection of specified microorganisms

For example, ISO 11930 provides a recognised approach for evaluating the antimicrobial protection of cosmetic products, while ISO 17516 addresses microbiological limits for cosmetics.

The appropriate method should be selected according to the product and purpose of the testing.

Microbiological Testing at Delta

At Delta, microbiological testing is considered as part of the wider product development and manufacturing process.

The testing program will depend on the product and stage of development and may include:

  • Bacterial, yeast and mould testing
  • Preservative efficacy testing

Results are reviewed against the requirements established for the product and can help determine whether the formulation can continue through development or whether further work is required.

Microbiological testing may also sit alongside stability testing and other product-specific testing as part of the development process.

How Long Does Microbiological Testing Take?

Timing depends on the type of testing being completed.

Preservative efficacy testing takes place over a defined testing period because samples need to be assessed at scheduled intervals.

Other microbiological testing may have shorter testing periods, depending on the method being used.

Brands should allow for testing within the wider development timeline rather than assuming it can be completed immediately before production.

If further formulation work or repeat testing is required, additional time may also need to be allowed.

When Should Brands Discuss Microbiological Testing?

Testing requirements are worth discussing while the product is still in development.

Brands do not need to arrive with a microbiological testing plan already prepared. The formulation, quality and manufacturing teams can help identify what needs to be considered for the individual product.

Discussing testing early also gives the brand a more realistic understanding of what needs to happen between approving a lab sample and progressing towards commercial manufacturing.

How Microbiological Testing Fits Into the Bigger Picture

Microbiological testing is one part of product development. It should be considered alongside the formulation, stability testing, packaging and manufacturing requirements.

The information gathered through testing can help development and quality teams understand how the product is performing and whether anything needs to be reviewed before the next stage.

For brands, the goal is not to become a microbiology expert. It is to understand why testing is part of the development process and what information it provides.

Working With Delta

Delta works with cosmetic and personal care brands from formulation development through to commercial manufacturing.

Depending on the product, microbiological testing can be considered alongside formulation development, stability testing and other requirements as the product progresses.

Connecting these stages within the wider development process gives brands a clearer understanding of what needs to happen before a product moves into commercial production.

Need Support With Microbiological Testing?

Speak to Delta about your product, testing requirements and the next steps towards commercial manufacturing.

Speak to Delta

SPF Regulations in AU, EU and US

Posted on by Stephanie Varchione

Sunscreen products are regulated differently depending on where they are sold.

A product developed for Australia may not meet the requirements of the United States or European Union without further review. Each market has its own rules around sunscreen ingredients, testing, claims, labelling and market entry.

For brands considering more than one market, it is worth understanding these differences early. Decisions made during formulation can affect where the finished product can be sold and what changes may be needed later.

This guide covers some of the main SPF regulatory considerations in Australia, the United States and European Union.

Why Do Sunscreen Regulations Differ Between Markets?

Sunscreens do not fall into the same regulatory category around the world.

In Australia, primary sunscreens and some secondary sunscreens are regulated as therapeutic goods.

In the United States, sunscreens are regulated as over-the-counter drug products.

In the European Union, sunscreens are regulated as cosmetic products.

The way a sunscreen is classified affects areas such as the UV filters that can be used, testing, claims, labelling and manufacturing requirements.

A sunscreen developed for one country should therefore be reviewed before it is introduced into another market.

Sunscreen Regulations in Australia

In Australia, the regulatory pathway depends on the type of sunscreen, what the product is intended to do and how it is presented to consumers.

The Therapeutic Goods Administration, or TGA, regulates sunscreens that fall within the therapeutic goods framework.

Primary and Secondary Sunscreens

A primary sunscreen is a product whose main purpose is protection from UV radiation.

A secondary sunscreen has another main purpose but also provides sun protection. Depending on the product, SPF and claims, some secondary sunscreens are regulated as therapeutic goods while others are excluded from therapeutic goods legislation.

For brands, this distinction matters because the requirements are not the same for every product containing SPF.

The regulatory pathway should be confirmed for the individual product before claims, artwork or launch plans are finalised.

Therapeutic Sunscreens and the ARTG

Therapeutic sunscreens generally need to be included in the Australian Register of Therapeutic Goods, known as the ARTG, before they can be legally supplied in Australia.

Most therapeutic sunscreens are listed medicines and carry an AUST L number on the label.

Listed therapeutic sunscreens need to meet the requirements that apply to the product. These may relate to:

  • Permitted ingredients
  • Claims and indications
  • Manufacturing
  • Testing
  • Labelling
  • Supporting evidence

The sponsor of a listed sunscreen is responsible for ensuring the product meets the relevant requirements and for holding the evidence needed to support it.

Australian Sunscreen Testing

The testing required will depend on the product and the claims being made.

For therapeutic sunscreens, this may include:

  • SPF testing
  • Broad-spectrum testing
  • Water-resistance testing, where relevant

The sponsor needs to hold appropriate evidence for the SPF and other applicable claims made for the product.

Australian Sunscreen Labelling

Therapeutic sunscreen labels also need to meet applicable Australian requirements.

Depending on the product, the label may need to include information relating to:

  • SPF
  • Broad-spectrum protection
  • Active ingredients
  • Directions for use
  • Required warnings
  • Storage conditions
  • Expiry
  • ARTG identification

Packaging and artwork should be considered alongside the regulatory pathway so required information can be incorporated before printing.

Sunscreen Regulations in the United States

In the United States, sunscreens are regulated by the Food and Drug Administration, or FDA, as over-the-counter drug products.

Sunscreen products marketed under the applicable over-the-counter framework need to meet FDA requirements relating to areas such as active ingredients, testing, claims and labelling.

UV Filters in the United States

The FDA specifies which sunscreen active ingredients can be used under the applicable over-the-counter framework and the conditions that apply to their use.

These requirements are not the same as those in Australia or the European Union.

If a brand intends to sell the same product in several markets, the proposed UV filter system should be reviewed for each region during formulation development.

SPF and Broad-Spectrum Claims

Sunscreen products sold in the United States need testing to support the SPF being claimed.

Products using a Broad Spectrum claim also need to meet the applicable FDA broad-spectrum requirements.

The claims available to the brand will depend on the product and the testing results.

Water-Resistance Claims

The FDA sets specific requirements for water-resistance claims.

Where supported by the required testing, products may use claims such as:

  • Water resistant (40 minutes)
  • Water resistant (80 minutes)

Claims such as waterproof, sweatproof and sunblock are not permitted under the FDA sunscreen framework.

Drug Facts Labelling

US sunscreen products use the Drug Facts format required for applicable over-the-counter medicines.

This includes information such as:

  • Active ingredients
  • Purpose
  • Uses
  • Warnings
  • Directions
  • Other required product information

For Australian brands entering the US market, this can have a significant impact on packaging and artwork because the label format differs from what is used for cosmetic products in other regions.

Sunscreen Regulations in the European Union

In the European Union, sunscreen products are regulated as cosmetics under Regulation (EC) No 1223/2009.

The regulatory pathway is different from Australia and the United States, but sunscreen products still need to meet requirements relating to formulation, safety, documentation, claims and labelling.

UV Filters in the EU

The EU Cosmetics Regulation sets out which UV filters can be used in cosmetic products and the conditions that apply to their use.

A UV filter system developed for another market should therefore be checked against EU requirements before the product is finalised.

This is particularly relevant for brands hoping to use one formulation across several regions.

EU Cosmetic Product Requirements

Sunscreens sold in the European Union are also subject to the broader requirements that apply to cosmetic products.

These include:

  • An EU-based Responsible Person
  • A cosmetic product safety assessment
  • A Cosmetic Product Safety Report
  • A Product Information File
  • Appropriate labelling
  • Notification through the Cosmetic Products Notification Portal before the product is placed on the market

Brands based outside the EU will need to establish who will act as the Responsible Person as part of their market-entry planning.

UVA and UVB Protection

European Commission guidance recommends that sunscreen products provide protection against both UVB and UVA radiation.

The recommended minimum UVA protection factor is at least one-third of the claimed SPF. A critical wavelength of at least 370 nm is also part of the recommended approach.

For brands, this means the SPF number is only one part of the overall protection profile that needs to be considered.

Sunscreen Claims in the EU

Sunscreen claims need to reflect the protection provided by the product and the evidence available to support them.

European guidance advises against claims that suggest complete protection from UV radiation or imply that sunscreen does not need to be reapplied.

Claims, directions and warnings should be reviewed as part of product development rather than added once the formulation is complete.

How Do Australia, the US and EU Differ?

The biggest difference between these markets is how sunscreen is regulated.

In Australia, primary sunscreens and some secondary sunscreens fall within the therapeutic goods framework. Therapeutic sunscreens generally require ARTG inclusion and need to meet applicable requirements for ingredients, manufacture, testing, evidence and labelling.

In the United States, sunscreens are regulated as over-the-counter drugs. Products need to meet applicable FDA requirements for active ingredients, testing, claims and Drug Facts labelling.

In the European Union, sunscreens are regulated as cosmetic products. Brands need to consider permitted UV filters, safety assessment, product documentation, Responsible Person obligations, notification and labelling.

A formulation that works in one market may need to be reviewed or changed before it can be supplied in another.

Can the Same SPF Formula Be Sold in Multiple Markets?

It may be possible, but it should be considered during development.

Markets can differ in the UV filters and concentrations they allow, how sunscreens are classified, the testing required and the claims that can be made.

Labelling and documentation requirements can also vary.

If international expansion is part of the plan, brands should tell their formulation and manufacturing team which markets are being considered at the beginning of the project.

This gives the team an opportunity to identify potential differences while the formulation is still being developed.

What Testing Should Brands Consider?

There is no single testing program that applies to every sunscreen in every market.

Testing depends on the product, the claims being made and where it will be sold.

Depending on those requirements, testing may include:

  • SPF testing
  • Broad-spectrum or UVA testing
  • Water-resistance testing, where relevant
  • Stability testing

Product development may also include:

  • Bacterial, yeast and mould testing
  • Preservative efficacy testing

Brands should confirm the testing requirements for their individual product and intended market rather than assuming one testing pathway will cover every region.

Planning an SPF Product for More Than One Market

Brands considering more than one country should start by being clear about where the product is likely to be sold.

Useful questions to discuss early include:

  • Which markets are being considered?
  • What type of SPF product is being developed?
  • What SPF does the brand want to achieve?
  • What claims are planned?
  • Are the proposed UV filters suitable for each market?
  • What testing will be required?
  • Will different packaging or artwork be needed?
  • Who will manage regulatory submissions or notifications?
  • What manufacturing requirements apply?

A brand does not need to have every answer before formulation begins. What matters is making the intended markets known early enough for them to be considered during development.

SPF Product Development at Delta

Delta works with skincare and personal care brands across SPF formulation development and commercial manufacturing in Australia.

When the intended markets are known early, the formulation and manufacturing teams can consider requirements that may affect the product as it develops.

Depending on the project, Delta can support:

  • SPF formulation development and refinement
  • Lab samples and product development
  • Stability testing
  • Planning for required external SPF testing
  • Manufacturing scale-up
  • Commercial manufacturing

Some regulatory activities and specialised testing may sit outside Delta’s role as manufacturer. Where this is the case, responsibilities should be agreed between the brand, sponsor and relevant regulatory or testing partners during development.

FAQ: SPF Regulations

Are sunscreens regulated differently in Australia, the US and EU?

Yes. Australia regulates primary sunscreens and some secondary sunscreens as therapeutic goods. The United States regulates sunscreens as over-the-counter drug products. The European Union regulates sunscreens as cosmetic products.

Do all Australian SPF products need to be listed with the TGA?

No. Primary sunscreens and some secondary sunscreens are therapeutic goods, while certain secondary sunscreen products are excluded from therapeutic goods legislation. The pathway depends on the individual product, its SPF, intended use and claims.

What testing is required for sunscreen in Australia?

The testing required depends on the product and claims being made. For therapeutic sunscreens, this may include SPF and broad-spectrum testing and water-resistance testing where relevant. The sponsor needs to hold appropriate evidence for the claims made.

How are sunscreens regulated in the United States?

Sunscreens are regulated by the FDA as over-the-counter drug products. Products marketed under the applicable sunscreen framework need to meet requirements relating to active ingredients, testing, claims and labelling.

How are sunscreens regulated in the European Union?

Sunscreens are regulated as cosmetic products under the EU Cosmetics Regulation. Requirements include permitted UV filters, product safety assessment and documentation, an EU Responsible Person, product notification and appropriate labelling and claims.

Can the same sunscreen formula be launched in several countries?

Potentially. However, ingredients, testing, claims, documentation and labelling requirements differ between markets. The intended regions should be considered during formulation development.

Developing SPF for More Than One Market?

Selling sunscreen internationally involves more than changing the label for a different country.

The formulation, testing, claims, packaging and regulatory pathway may all need to be reviewed for each market.

For brands considering Australia and future international expansion, discussing intended markets early gives the formulation and manufacturing team a clearer picture of the product being developed.

Planning an SPF Product?

Speak to Delta about your product brief, intended markets and commercial manufacturing requirements.

Speak to Delta

Product Stability Testing

Posted on by Stephanie Varchione

Product stability testing helps manufacturers understand how cosmetics, personal care products and pharmaceuticals perform over time under defined storage conditions. By assessing products under defined storage conditions, stability testing provides information about how formulations change over time and whether further development work may be required. Working with an experienced manufacturing partner like Delta helps brands plan stability testing as part of the wider product development and manufacturing process.

What Is Product Stability Testing?

Product stability testing evaluates how a product’s physical, chemical and microbiological properties change over time under different environmental conditions. The goal is to monitor how a formulation changes over time and assess whether it continues to meet its defined specifications.

For manufacturers, stability testing provides the scientific data needed to support:

  • Shelf-life assessment
  • Product specifications
  • Relevant regulatory requirements
  • Ongoing product development decisions

A structured stability testing protocol provides a consistent way to monitor the product over time and record any changes that may need further investigation.

Purpose and Importance

Stability testing helps answer critical questions during product development and regulatory review:

  • How does the product change over time under defined storage conditions?
  • Will the formulation separate, degrade or change colour?
  • Does the packaging protect the product adequately?
  • How do defined temperature and humidity conditions affect the product over time?

For cosmetic and pharmaceutical products, stability testing provides useful information during development and can help identify whether further formulation or product review is required before launch.

Types of Stability Testing

A stability testing program may assess several characteristics, depending on the product and its requirements.

Physical Stability

Physical testing looks at visible and structural changes in the product, such as:

  • Colour changes
  • Phase separation
  • Texture or viscosity changes
  • Sedimentation or crystallisation

These factors can affect both product performance and consumer perception.

Chemical Stability

Where relevant, stability testing may include analytical testing to monitor specified active ingredients over time. The testing required will depend on the product type, formulation and applicable requirements.

Microbiological Stability

Microbiological testing can be included as part of the testing program where relevant to the product. This is particularly important for water-based cosmetic formulations.

Testing may include:

  • Bacterial, Yeast and Mould testing
  • Preservative efficacy testing

How Delta Performs Stability Testing

At Delta, stability testing is designed to provide data that supports product development and relevant regulatory requirements.

Protocol Development

A stability study begins with a testing protocol developed around the product and its requirements.

This protocol typically defines:

  • Testing duration
  • Storage conditions
  • Sampling intervals
  • Analytical tests to be performed
  • Acceptance criteria

The protocol sets out how the study will be conducted and how results will be assessed over the testing period.

Temperature and Humidity Conditions

Environmental conditions play a major role in product stability. Testing commonly evaluates how formulations respond to different temperature and humidity levels over time.

At Delta, 30°C / 65% RH is a typical long-term stability condition.

Stability Testing for Cosmetics and Pharmaceuticals

Different industries have specific regulatory expectations when it comes to stability testing.

Key Industry Requirements

Stability requirements vary depending on the type of product and its regulatory pathway.

For pharmaceutical or therapeutic products, stability data may be required to support:

  • Expiry dating
  • Storage conditions
  • Product registration

The testing program should be developed with the relevant product and regulatory requirements in mind.

Interpreting Stability Test Results

Collecting stability data is only part of the process. The results are reviewed to assess how the product is performing against its defined specifications over the study period.

Data Reporting and Actions

At scheduled intervals during a stability study, samples are tested and the results are recorded. These data points help identify trends such as:

  • Changes in relevant product specifications
  • Changes in pH or viscosity, where applicable
  • Microbiological results, where relevant
  • Observations that may require further investigation

If results fall outside the expected specifications, further review or development work may be required.

Why Choose Delta

Choosing an experienced manufacturing partner is important when planning and managing stability testing. Delta supports cosmetic, personal care and pharmaceutical manufacturers through:

  • Stability testing protocols developed around the product and its requirements
  • Long-term and accelerated stability studies, where applicable
  • Recording and reporting of stability results
  • Stability testing as part of the wider product development process

With practical experience across product development and manufacturing, Delta helps brands understand how their products perform over time and make informed decisions before market launch.

Need support with product stability testing?

Delta works with cosmetic, personal care and pharmaceutical brands to develop stability testing programs suited to the product and its requirements.

Speak with Delta’s team about stability testing requirements for your product.

Contact Delta