End-users

Our biodegradable plastic, PHA, is aimed primarily at the agricultural sector, with farmers as our key stakeholders. PHA's biodegradability aligns with legal requirements and economic incentives, such as regulations on fertilizer coatings1 and the economic benefits of degradable mulch film.

Experts we interviewed have also substantiated private consumers as another group of end users of PHA. Our product appeals to environmentally aware individuals who value sustainable agriculture and want to support ecologically friendly practices. Additionally, private consumers value PHA for its sustainability, which empowers farmers, appeals to environmentally conscious consumers, and supports eco-friendly practices in the food supply chain. By offering a biodegradable plastic solution tailored to the unique needs of the agricultural industry, PHAse Out contributes to a more sustainable and responsible future in farming.

Product design

Defining the issue

Microplastic pollution in agriculture presents a pressing environmental challenge with widespread implications for ecosystems and human health. This issue is particularly pronounced in the Netherlands, where hundreds of tons of plastic are used annually for various agricultural purposes such as crop protection and irrigation systems2. Worldwide, the global demand for mulching films is also projected to increase by about 50 percent by 2030, further highlighting the seriousness of the problem3. The consequences of microplastic pollution in agriculture are wide ranging and encompass soil degradation, water contamination, and threats to wildlife and human consumers4. Addressing the microplastic problem demands innovative solutions and a shift towards more sustainable plastic practices in agriculture to mitigate the adverse effects on our environment and food supply.

Current solutions to the microplastics issue

    Numerous solutions have been developed and implemented to address the microplastic contamination brought on by unsustainable agricultural practices and several solutions are being developed and deployed. These solutions encompass a range of approaches, including implementation of biodegradable plastics, recycling initiatives within the farming community, and the implementation of precision farming techniques to reduce plastic usage5, 6. Additionally, some farmers are exploring alternative materials for packaging and crop protection, such as natural fibers and bio-based materials. regulations and incentives to encourage responsible plastic disposal and recycling are also being considered to address this pressing issue7. The European Union took significant action in 2018 by introducing new legislation and a strategic plan aimed at promoting a circular economy and to contribute to reaching the UN’s Sustainable Development Goals8. However, most of the current solutions to agricultural plastic pollution are still lacking in several key areas. Recycling initiatives face challenges such as the complexity of collecting and processing plastic waste from dispersed rural areas9. The adoption of both precision farming techniques and alternative materials is slow due to the upfront costs and the resistance to change within the agricultural industry10. Moreover, the absence of comprehensive regulatory frameworks and financial incentives often hamper the widespread adoption of sustainable practices. Lastly, many of the bioplastics currently in production are derived from carbohydrate-rich plants such as sugarcane or corn, which leads to competition with food production.

    Polyhydroxyalkanoates (PHA) is a promising solution that may help combat agricultural plastic pollution. PHA has demonstrated superior biodegradability in a natural environment compared to other biodegradable plastics on the market, which only break down in industrial composting conditions (at temperatures exceeding 58 °C )11. PHA degradation takes place naturally in all conditions and results in non-toxic compounds12, 13. Additionally, PHA can be produced from renewable resources, such as methanol, offering a more sustainable source for plastic materials14, 15, 16. Its potential to replace conventional plastics, coupled with its minimal environmental footprint and ideal biodegradability, makes PHA a strong candidate for mitigating plastic pollution in agriculture.

Product Design

In our pursuit of creating the ideal product, we engaged in constructive dialogues with a multitude of stakeholders. Their feedback played a crucial role in shaping the (experimental) design of our final product, ensuring it meets the end-users needs and the required standards. Read more about the interviews with experts and stakeholders, and the lessons we learned from them.

Additionally, extensive literature research was done in search for the optimal properties of biodegradable plastics for agricultural use. The ideal characteristics for biodegradable plastics in agricultural films are listed below17,18:

  • Proper plastic life expectancy. A necessary balance between resistance, strength and flexibility

  • Optical and thermal properties

  • Weight. Weight is a crucial factor to take into account, as it varies depending on the soil type and the specific cultivation needs. Different types of plastic films, with varying weights, are required to suit these diverse conditions.

  • Density. Density plays a significant role, particularly in the analysis of polymer crystallinity. This examination is critical as it directly impacts the flexibility, permeability, and thermal characteristics of the polymers. Adjustments are necessary based on the density of these polymers. Lower density plastics offer advantages in terms of ease of handling and transportation.

  • Thickness. The optimal thickness a plastic film must have to protect crops, especially when there are low temperatures, is 200 - 800 microns.

  • Tensile strength is a critical attribute that guarantees the durability of the film, particularly in regions prone to adverse weather conditions such as hail, snow, or powerful winds. Plastics with robust tensile strength characteristics are better equipped to withstand deformation caused by extreme temperature fluctuations, ensuring long-term durability.

The ideal characteristics for biodegradable plastics in fertilizer coatings are listed below19:

  • Cost effective formulation (not more than 2 EUR/kg, the upper cost limit will be application dependent)

  • Biodegradable in soil

  • Tunable to a variety of application requirements

Proof of concept: PHA degradation experiment

To assess the biodegradability of PHA, we performed a degradation experiment. To create a sheet, we dissolved PHA pellets in DMC and poured this in a petridish. We compared the degradation of the PHA sheet to the degradation of a polyethylene sheet of equal size and thickness, by incubating the sheets on a bed of moist soil at room temperature. This setup was stored in a plastic bag to retain humidity. A picture was taken at regular intervals to create a timelapse of the degradation over a 1.5 month period. The left side is PHA and the right side is polyethylene.

Implementation

Implementation steps

lab-lines
Fig. 1 | The eight steps of our implementation plan.



We mapped out eight crucial steps for achieving successful implementation, illustrated in Figure 1. This visual representation maps the progression of our plastic, from the inception to becoming sustainable agriculture product. These steps describe not only the practical facets that are essential for a successful business, but also emphasize safety measures aimed at safeguarding consumers, crops, farmers and the environment.

1. Market Research

    Conducting comprehensive market research is essential to identifying potential applications and industries for our PHA. Tailoring the product to specific market needs will enhance its adoption. Our collaboration with market research experts and industry professionals provided us with valuable insights. You can read more on this on our Human Practices page and our Entrepreneurship page . We should regularly update our market analysis to stay informed about evolving trends and demands.

2. Methanol Procurement

    Ensuring a stable methanol supply begins with securing reliable suppliers or forging long-term contracts, establishing a dependable supply. To mitigate potential disruptions, it's crucial to diversify sources, considering both green energy based and bio-based methanol production options. Building strategic partnerships with suppliers allows for negotiation of favorable terms and assures priority access to methanol resources, reducing the risk of supply shortages20. Staying vigilant and continuously monitoring market trends and global methanol supply dynamics empowers your team to adapt procurement strategies proactively, ensuring a resilient supply chain.

3. Scale-Up Process

    Transitioning from the laboratory to industrial scale begins with pilot-scale experiments to validate the process's scalability. This can be done either through investing in larger equipment and collaborating with experts in engineering or through licensing and outsourcing. There is no literature available where M. extorquens is cultivated on an industrial scale. Therefore, to execute successful large scale bioproduction, experiments will be conducted to obtain adequate protocols.

4. Safety Protocols

    Safety measures are paramount in the production facility. Establish a dedicated safety committee responsible for developing and updating protocols. Comprehensive safety training programs ensure all personnel adhere to safe practices. Access controls and safety measures within the facility should be strictly enforced, with regular audits for continuous improvement. Read more about our project’s safety measures .

5. Quality Control

    Maintaining PHA quality necessitates a well-equipped quality control laboratory. We should develop a quality assurance plan, including routine testing for purity, molecular weight distribution, and mechanical properties. We should also implement a traceability system for batch tracking and collaborate with third-party organizations for validation and certifications.

6. Regulatory Compliance

    Navigating the complex regulatory landscape requires a dedicated compliance employee to ensure adherence to safety, environmental, and product quality regulations. To achieve this, we should maintain records and documentation of all production processes and safety measures, stay updated on changing regulations, and proactively adjust procedures accordingly. We have developed a preliminary understanding of this landscape through interviews with Thomas Leppin, an EU regulatory expert, and the Dutch regulatory authority on public health and the environment (RIVM). You can read both interviews .

7. Environmental Impact Assessment

    We should conduct a comprehensive environmental impact assessment to evaluate the ecological footprint of your PHA production process. Identify opportunities for resource conservation, waste reduction, and emissions minimization. Invest in sustainable technologies and practices to mitigate negative environmental effects. Continuously monitor and report on your environmental impact to demonstrate our commitment to sustainability.

8. Continuous Innovation

    Maintain a strong focus on ongoing research and development to remain at the forefront of PHA technology. Encourage a culture of innovation within the research team. Invest in cutting-edge research equipment and facilities. Regularly benchmark your production processes against industry best practices and emerging trends. Seek opportunities for patenting innovative technologies to maintain a competitive edge.

Sustainability

In our project, sustainability has a central role, as our use of green methanol is a key component of the project. Methanol stands out as a carbon-neutral alternative to other microbial feedstocks used for PHA production20. This innovative approach not only reduces our project's carbon footprint but also contributes to the broader goal of mitigating greenhouse gas emissions. By utilizing green methanol, we are actively addressing environmental concerns and fostering a sustainable production process. This choice reflects our dedication to ensuring that every aspect of our project aligns with principles of ecological responsibility and environmental stewardship. You can read more about the sustainability of our project on the Sustainable Development page .

Future vision & challenges

After having improved the production and extraction of PHA biodegradable plastic, we expect to face several challenges that should be addressed when implementing our project.

Safety

There is little research published on the toxicity of PHA to humans and animals. There are some studies that claim that bio-based and/or biodegradable materials are just as toxic as conventional plastics with regards to the chemicals they contain. The writers of the article imply that in order to develop bio-based/biodegradable materials that indeed outperform conventional plastics, sustainability and chemical safety aspects must be addressed alike21. Because we are using GMOs in the production of PHA, safety is crucial. Additionally, working with hazardous chemicals may be involved in the PHA extraction process, depending on the protocol used. You can read more on these safety considerations on our Safety page .

Challenges

Despite its potential, the widespread adoption of PHA faces challenges such as higher production costs compared to traditional plastics, limited scalability of production, and competition from well-established plastic materials22. The production of PHA requires microbial processes, which can be energy-intensive and costly to scale up for mass production23. According to methanol expert Alberto Pettinau , another key problem is that the cost of renewable methanol is typically 2 to 3 times higher than the conventional market price of fossil derived methanol. Furthermore, PHA plastics also exhibit different material properties compared to traditional plastics, making it necessary to develop new manufacturing techniques and adapt to the specific needs of different industries. For instance, applications expert Jesse Hiemstra informed us that a new mold for the production of PHA products could cost up to 60.000 euro’s. He also highlighted that regulatory frameworks and consumer acceptance also play significant roles in the successful adoption of PHA plastics. You can read the full interview with Jesse Hiemstra here . As of now, more research is needed to overcome these difficulties and increase the viability of PHA economically.

Conclusion

The success of implementing our PHA into real-world applications involves several factors. It's crucial to have a comprehensive understanding of end-users and stakeholders, as they will be the primary beneficiaries of our project. Identifying the problem we aim to solve is foundational to our product design. Expert and stakeholder interviews, along with extensive literature research, have guided us in determining the desirable properties for our agricultural product. Our implementation steps are guided by principles of ecological responsibility and human and environmental safety. All aspects of our project adhere to these principles. We have also considered potential challenges in the implementation process. Through this thorough implementation plan, we hope to be able to help safeguard our food and health.

References

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