Microbiological Efficacy Tests for Biocidal Products: The Scientific Basis for Market Authorization

Biocidal products encompass a wide range of products—such as disinfectants, antiseptics, preservatives, pesticides, and pest control agents—that are intended to control microorganisms or harmful organisms. In order for these products to be placed on the market, their claimed efficacy must be scientifically demonstrated. Microbiological efficacy tests measure the killing or inhibitory effect of a biocidal product on target microorganisms under standardized conditions.

An efficacy test for biocidal products is not only a regulatory requirement but also forms the basis for the reliability of a product’s marketing claims. Without efficacy data, it is not possible to obtain authorization for a biocidal product. Therefore, the proper design of the tests, their conduct in accordance with applicable standards, and comprehensive reporting directly influence your product’s authorization process.

The Scientific Basis of Microbiological Efficacy Tests

Microbiological efficacy tests are based on the quantitative measurement of a biocidal product’s effect on target microorganisms at a specific concentration, for a specific exposure time, and under specific conditions. The primary result of the test is the logarithmic reduction value (log reduction), which is calculated as the difference between the initial number of microorganisms and the number after the test. For example, a 5-log reduction means that the initial number of microorganisms has decreased by a factor of 100,000 and represents a commonly required threshold for the efficacy of disinfectants.

Test design depends on factors such as the target microorganism species, the product’s intended use (personal care, food-contact surfaces, hospital environments, veterinary facilities), contact time, temperature, and organic load. By adding organic contamination (dirt, serum, proteins) to the test conditions, the product’s performance under real-world conditions can be simulated more accurately. For this reason, efficacy tests are conducted according to different standards depending on the product class and application scenario.

Biocide efficacy tests are classified into three main groups based on the product’s specified spectrum of activity: bactericidal (bacteria-killing), fungicidal (fungus-killing), and virucidal (virus-killing) efficacy. In addition, depending on the product specifications, sporicidal (spore-killing), mycobactericidal (mycobacteria-killing), and tuberculocidal efficacy tests may also be required. Different reference strains of microorganisms and different standards are used for each type of efficacy.

Efficacy Tests by Product Category

Biocidal products are subject to different efficacy testing requirements depending on their intended use. Tests for disinfectants are conducted according to different standards depending on the area of application (human health, veterinary medicine, food, household). For disinfectants used in hospitals, bactericidal and fungicidal efficacy under conditions of high organic load are required; additional virucidal tests are necessary for virucidal claims. Tests for antiseptics are designed to evaluate their efficacy on the skin and mucous membranes. For preservatives (used in cosmetics, pharmaceuticals, and industrial products), a test of preservative efficacy—known as a challenge test—is conducted; this test evaluates whether the product provides protection against microbial contamination throughout its entire shelf life.

Tests for hand sanitizers are conducted in accordance with specific standards such as EN 1500 (hygienic hand disinfection) and EN 12791 (surgical hand disinfection). For surface disinfectants, the standards EN 1276 (bactericidal), EN 1650 (fungicidal), and EN 14476 (virucidal). For instrument disinfectants, the standards EN 13727, EN 14561, and EN 14476 apply. Each standard defines different requirements regarding test microorganisms, contact time, organic load, and acceptance criteria.

The following table summarizes the efficacy testing standards applied, organized by the main classes of biocidal products.

Test Parameters

Test parameters include exposure time, temperature, organic load, and product concentration. Each of these parameters must be maintained within the ranges specified in the standard; otherwise, the results are considered invalid. To ensure the reproducibility of the test, all steps must also be performed in accordance with standard operating procedures (SOPs) and properly documented. Our laboratory reports on all tests in accordance with GLP principles, ensuring traceability and providing complete quality control data.

BPR and the Regulatory Framework

In the European Union, biocidal products are authorized in accordance with the BPR (Biocidal Products Regulation—528/2012). The BPR requires that efficacy tests appropriate for the product’s stated spectrum of activity be conducted to demonstrate its efficacy. Efficacy data are an essential part of the product’s authorization application, and without this data, the application will not be accepted.

Under the BPR, efficacy tests are evaluated by the competent authority of the respective Member State based on the intended use of the product. The tests must be conducted in an accredited laboratory under GLP or GMP conditions, and the results must be fully documented. In addition, the product’s stated spectrum of activity must correspond to the instructions for use listed on the label; discrepancies between the efficacy data and the information on the label can lead to serious problems during the authorization process.

Scope of Services Offered by Our Laboratory

Our GLP-certified laboratory conducts bactericidal, fungicidal, and virucidal efficacy tests for biocidal products in accordance with the relevant EN standards and the requirements of the BPR.
Our testing procedure begins with an evaluation of the product’s properties and the specified spectrum of activity; subsequently, the appropriate standard, test microorganisms, and test conditions are determined. The tests are conducted using validated methods and are accompanied by quality control data.

Testing for biocidal efficacy is a critical component of the approval process for your product.
The right standards, an appropriate test design, and comprehensive reporting prevent delays in the approval process and ensure the reliability of the information about your product. Our laboratory provides the scientific infrastructure and regulatory expertise you need throughout this entire process.

Frequently Asked Questions

What efficacy tests are required for my product? The required tests depend on the product’s intended use and its stated spectrum of activity. For disinfectants, bactericidal, fungicidal, and virucidal tests are required depending on the intended use; for preservatives, a challenge test is required; and for antiseptics, efficacy tests on the skin and mucous membranes are required. Our laboratory determines the required test list based on the properties of your product.

How long do the tests take? The duration of the tests varies depending on the type of efficacy and the standard. Bactericidal and fungicidal tests typically take 2–4 weeks; virucidal tests can take 4–6 weeks due to the cell culture phases.
Including report preparation and quality assurance checks, the total duration is 4–8 weeks.

Can an application for authorization be submitted without efficacy data? No. According to the BPR and the Turkish Biocidal Products Regulation, efficacy data is a mandatory component of the application for authorization. Applications without efficacy data will not be accepted.

Contact our laboratory to scientifically demonstrate the efficacy of your biocidal product and expedite your authorization process. Our team of experts will develop a testing strategy tailored to your product and provide you with a comprehensive set of all necessary efficacy data.