Soil Biodegradation Study

Symphony Environmental Tech. PLC

07 September 2026

 

7 September 2026

SYMPHONY ENVIRONMENTAL TECHNOLOGIES PLC

(the "Company")

Comprehensive Soil Biodegradation Study Confirms Mineralisation of Symphony's d2w® Plastics with No Microplastics and No Ecotoxicity

Symphony Environmental Technologies Plc (AIM: SYM), the global specialists in technologies that make plastic and rubber products smarter, safer and more sustainable, is pleased to announce the successful completion of an extensive independent testing programme comprising reports of eight tests conducted by the ISO 17025-accredited laboratory of Intertek India Pvt Ltd ("Intertek") between February 2025 and May 2026 on polymer films incorporating Symphony's d2w® technology. The programme evaluated abiotic degradation, biodegradation, ecotoxicity, and the absence of microplastic particles.

The testing programme was conducted in accordance with ASTM D6954, an internationally recognised standard guide for evaluating plastics that degrade in the environment through a combination of oxidation, biodegradation, together with ecotoxicity assessment. ASTM D6954 provides a structured three-tier framework consisting of:

·      Tier 1: Abiotic degradation

·      Tier 2: Biodegradation

·      Tier 3: Ecotoxicity assessment

The ASTM D6954 framework is used internationally to evaluate the environmental behaviour of plastics under defined laboratory conditions relevant to their intended use and disposal environments. Environmental parameters may be adjusted by regulators and policymakers to reflect local climatic and environmental conditions.

As part of the Tier 1 evaluation, the material underwent accelerated abiotic degradation in accordance with ASTM D5208, resulting in a reduction of molecular weight to approximately 2,200 Daltons and meeting the ASTM D6954 requirements for progression to biodegradation testing. The material also exhibited only 3.1% gel formation, well below the maximum levels contemplated by ASTM D6954.

Following Tier 1, the material was subjected in 2026 to biodegradation testing in soil under ISO 17556, "Plastics - Determination of the ultimate aerobic biodegradability of plastic materials in soil." After 600 days under controlled soil conditions, the material achieved 98.7% mineralisation.

At the conclusion of the biodegradation process, the resulting biomass was analysed by Intertek using analytical methodologies developed with reference to ISO 24187 ("Principles for the analysis of microplastics present in the environment"), employing micro-FTIR spectroscopy, scanning electron microscopy (SEM), and associated analytical techniques. Intertek reported that there were no microplastic particles in the resulting biomass, and that the absence of original polyethylene in the biomass shows complete mineralisation of the original sample.

In addition, the resulting biomass was evaluated for ecotoxicity in accordance with internationally recognised OECD methods 207 (Earthworm Acute Toxicity Test) and OECD 208 (Terrestrial Plant Test). There were no adverse effects on earthworm survival, plant growth, or seed germination. The sample passed Tier 3 ecotoxicity assessment and demonstrated no harmful environmental effects.

Growing Scientific Evidence Addressing Global Plastic Pollution Concerns

The significance of these findings extends beyond the successful completion of this test programme.

These studies form part of Symphony's long-term commitment to generate independent scientific evidence from accredited laboratories regarding the environmental fate of plastics incorporating d2w® technology. As governments, regulators, brand owners, and consumers seek practical responses to plastic pollution, increasing attention is being directed towards persistence in the environment, microplastics, and potential ecological impacts.

The Company believes that this programme of studies represents the most comprehensive evaluation ever undertaken on an oxidative biodegradable polyethylene technology, integrating abiotic degradation, biodegradation, ecotoxicity assessment, and microplastic investigation within a single programme. Importantly, the testing was conducted using internationally recognised standards and methodologies specifically designed to evaluate environmental performance.

Unlike many biodegradation standards which focus primarily on industrial composting, ISO 17556 assesses aerobic biodegradation directly in soil. The results are therefore particularly relevant to terrestrial environments where mismanaged plastic waste may ultimately accumulate.

Michael Laurier, CEO of Symphony Environmental, said:

"This is not simply another successful laboratory test. It is an important addition to a substantial body of scientific evidence demonstrating that plastics made with d2w® technology do not behave like conventional plastics at the end of their service life.

Around the world there is increasing concern about plastic pollution and microplastics, but there remains considerable misunderstanding about technologies that have been specifically developed to address these challenges. Our policy has always been to follow the science and invest in rigorous independent testing using internationally recognised standards and methodologies and duly accredited test-houses.

The Board considers these independent verified findings to represent a significant enhancement of Symphony's scientific and regulatory evidence base and to be materially relevant to the Company's future commercial and regulatory opportunities.

The results announced today demonstrate that after extensive testing in soil there were no microplastic particles in the resulting biomass and no adverse effects on plant growth or earthworms. Combined with previous independent studies by Queen Mary University, London, the French Oxomar project, and others, these findings strengthen the scientific evidence supporting d2w® technology as a practical solution for reducing the persistence of plastic in the environment.

Importantly, these results show that the discussion should not be about whether plastics are inherently a problem. Plastics provide enormous economic, social, medical and environmental benefits. The challenge is ensuring that plastics are designed and managed responsibly throughout their life cycle and, where recovery is not possible, that they do not persist in the environment.

We believe that Symphony's growing portfolio of independent scientific evidence provides policymakers, brand owners and consumers with objective scientific data relevant to concerns about persistence, microplastics and environmental safety, whilst preserving the many benefits plastics bring to society.

As governments around the world continue to develop policies to address plastic pollution, we will continue to maintain that decisions should be based on sound science and objective evidence."

Enquiries

Symphony Environmental Technologies Plc
Michael Laurier, CEO		Tel: [phone]
Ian Bristow, CFO
www.symphonyenvironmental.com
Zeus (Nominated Adviser and Broker)
David Foreman (Investment Banking) Dominic King (Broking)		Tel: [phone]

Notes to Editors

The testing programme utilised the following international standards:

·      ASTM D6954 - Standard Guide for Exposing and Testing Plastics that Degrade in the Environment by a Combination of Oxidation and Biodegradation.

·      ASTM D5208 - Standard Practice for Fluorescent Ultraviolet (UV) Exposure of Photodegradable Plastics.

·      ISO 17556 - Determination of the Ultimate Aerobic Biodegradability of Plastic Materials in Soil.

·      OECD 207 - Earthworm Acute Toxicity Test.

·      OECD 208 - Terrestrial Plant Test.

·      ISO 24187 - Principles for the Analysis of Microplastics Present in the Environment.

Further information can be found at: Symphony Environmental Technologies

Symphony also supplies a range of plastic technologies under its d2p (designed to protect) brand to provide protection against insects, viruses, bacteria, fungi, rodents, odours, food deterioration, and fire. www.d2p.net  .

Symphony also provides a tag/trace system under its d2t brand, to protect against counterfeiting and to prove the recycled content of plastic products.

It has also introduced a new product under its NbR brand https://www.symphonyenvironmental.com/natural-biodegradable-resin/   to reduce the amount of fossil-derived material in plastic products, and to reduce associated carbon-emissions.

Symphony has a diverse and growing customer base and has established itself as an international business with more than 70 distributors around the world. Products incorporating Symphony technologies are available in nearly 100 countries across a broad range of applications. The Company is certified to ISO 9001 and ISO 14001 and actively participates in standards-development activities through BSI, ASTM, CEN and ISO. It holds the London Stock Exchange Green Economy Mark

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Further information on the Group can be found at www.symphonyenvironmental.com 

 

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