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Environmental impacts of conventional plastic and bio-based carrier bags
The International Journal of Life Cycle Assessment
Abstract and Figures
Background, aim, and scope
The use of bio-based products as carrier bags, packaging materials, and many other applications has been increasingly replacing conventional polymer products. One of the main driving forces of bio-plastic applications is the perceived depletion and scarcity of fossil fuels, especially petroleum. However, despite being introduced as an environmentally friendly alternative to plastics made from crude oil, the environmental benefits of bio-plastics remain debatable. This article serves to investigate whether or not bio-based materials are environmentally friendlier options compared to plastics and attempts to explain the rationale of the results.
Materials and methods
The production and disposal of both conventional plastic and bio-plastic carrier bags are investigated using life cycle assessment or LCA. A typical bio-based bag (made from polyhydroxyalkanoate or PHA) from the U.S. was selected to be compared with a locally produced polyethylene plastic (PP) bag in Singapore. In the LCA system, the raw materials for making polyethylene came from crude oil imported from Middle East and natural gas piped from Natuna gas field. The refinery and PP bag production processes are based in Singapore. Bio-bag production was entirely in the U.S., and the finished product was shipped to Singapore. The impact assessment results were generated for global warming potential, acidification, and photochemical ozone formation. Next, normalized results were calculated according to the parameters of Singapore’s annual emission inventory.
Results
The total environmental impacts of bio-bags showed considerable differences under various energy scenarios. When the energy expenditures to make bio-bags are supplied by U.S. electricity mix, the production impacts are about 69% higher, compared to the impacts from PP bags. With coal-fired power supply, the production impacts from bio-bag production turned out to be about five times greater than those from conventional plastics. The life cycle production impacts of PP bags are comparable to bio-bags when the energy supplied to the bio-material production chain is supplied by natural gas. Bio-bags are 80% more environmentally friendly than plastic bags when clean and renewable energy (geothermal) is used throughout its life cycle production stages.
Discussions and conclusions
By the use of LCA with different energy scenarios, this article sheds some light on the extent of environmental benefits (or drawbacks) of replacing plastic carrier bags with PHA bags. It was concluded that the life cycle production of bio-bags can only be considered as environmentally friendly alternatives to conventional plastic bags if clean energy sources are supplied throughout its production processes. It was also highlighted that the results should not be viewed as a global representative since the case study scope was for Singapore alone. Additional work by others on different biodegradable and compostable bags vary in results. Some of the complexities of such work lie in what is included or excluded from the scope and the adoption of different environmental impact assessment methods. Nevertheless, the authors’ attempt to compare the two bags may serve as a basis for identifying the major environmental burdens of such materials’ life cycle production.
Recommendations and perspectives
Although bio-based products have been mostly regarded as a sustainable solution for replacing petroleum-based polymers, in most cases, the amounts of resources and energy required to produce them have not been taken into account. Before bio-based plastics can be recommended as a preferred option to plastics, a few challenges have to be overcome. The main issue lies in reducing the energy used in the life cycle production of the bio-material from crops. The environmental benefits and drawbacks of both materials should also be more clearly highlighted by expanding the system boundary to include end-of-life options; this is carried out in part 2 (Khoo and Tan, Int J Life Cycle Assess, in press, 2010).
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... • Environmental concerns: Despite their eco-friendly promise, the processes involved in bio-based product recovery may entail environmental costs, including energy consumption, water use, and waste generation, necessitating a holistic sustainability assessment. 75 Life cycle assessments (LCA) of bio-based products must consider these factors to ensure that their overall environmental impact is lower than that of their fossil-based counterparts. The development of more efficient and less resource-intensive bioprocesses is critical in addressing these concerns. ...
This article investigates the integration of circular economy methodologies and biorefinery concepts for the sustainable recovery of bio‐based products from industrial effluents, addressing the critical need for resource efficiency and environmental sustainability in the face of climate change and resource depletion. Emphasizing the valorization of industrial by‐products, the study explores innovative, eco‐friendly recovery processes within a biorefinery framework to transform waste into valuable resources such as biofuels, biochemicals, and biomaterials. Through a systematic search in various bibliographic databases and a comprehensive literature review, the study critically analyzes existing studies, identifies research gaps, and offers new perspectives on the integration of biorefinery and circular economy principles. The findings reveal that strategic integration of biorefinery processes and circular economy principles can significantly reduce environmental footprints and foster sustainable industrial practices. Key challenges such as feedstock variability, technological barriers, and economic scalability are identified, along with recommendations for overcoming these obstacles through interdisciplinary collaboration, technological innovation, and supportive policy interventions. The main contribution of this research lies in its comprehensive approach, integrating cutting‐edge technologies and circular economy principles to offer viable strategies for sustainable bio‐based product recovery, thus significantly advancing the field of industrial sustainability. The article contributes to the advancement of sustainable technologies, policies, and strategies, advocating for a transition towards a more circular, resource‐efficient industrial sector. Continued innovation and research are emphasized to optimize recovery processes and explore new applications, supporting a sustainable and thriving future for our planet.
... Bioplastics consumes higher amount of non-renewable energy use (NREU) as compared to petro-plastics (Troschl et al., 2017), which results in the release of GHG in the environment (Yates and Barlow, 2013). Moreover, emission of SO 2 from NREU can cause water pollution and acid rain can be caused by emission of other chemicals (Khoo et al., 2010). However, a potential solution to this problem can be the adoption of renewable energy instead of NREU. ...
... Simultaneously, the escalating global plastic crisis has resulted in severe environmental repercussions, with plastic waste polluting oceans, harming wildlife, and contributing to long-lasting ecological damage [14]. Conventional plastics, primarily derived from non-renewable fossil fuels, pose a signi cant challenge due to their non-biodegradable nature [15]. In response to these pressing issues, the demand for sustainable alternatives is on the rise. ...
This study presents the synthesis of agrowaste banana peel extract-based magnetic iron oxide nanoparticles (BPEx-MIONPs), emphasizing antioxidant capacity and food preservation. Using iron (III) chloride hexahydrate (FeCl 3 · 6 H 2 O) as a precursor and a reducing agent from agrowaste peel extract, a precisely controlled process yielded BPEx-MIONPs. Characterization involved X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy (FTIR). XRD revealed tetragonal Fe 2 O 3 , cubic magnetite structure, and monoclinic FexOy-NPs with an average size of 14.8 nm. TEM and SEM showcased diverse morphologies—cubic, quasi-spherical, and elongated microdomains. FTIR confirmed Fe–O bonds (1000 − 400 cm ⁻¹ ). Antioxidant assessment showed robust DPPH free radical scavenging; BPEx achieved 100% inhibition at 18 min, and BPEx-MIONPs had an IC 50 of ~ 136 µg/mL. BPEx-MIONPs, stabilized with banana-based bioplastic, effectively preserved grapes, reducing weight loss to 6.2% on day 3, compared to the control (19.0%). This pioneering study combines banana peel antioxidants with magnetic iron oxide nanoparticles, providing sustainable solutions for food preservation and nano-packaging. Ongoing research aims to refine conditions and explore broader applications of BPEx-MIONPs.
... It is worth adding that the challenge is to develop compostable packaging that will ensure the lowest possible level of environmental impact throughout the lifecycle. There is still discussion on whether bio-based materials are environmentally friendly options compared to plastics in terms of lifecycle assessment (Khoo et al., 2010). Second, future transformation of the bio-packaging regime depends on the adaptation of technological innovations on an industrial scale. ...
Purpose-The purpose of this article is twofold. First, this study characterises the current state of the bio-packaging market's development. Second, it identifies key factors influencing and possible scenarios of the bio-packaging market transition to increase the market share of compostable packaging. Design/methodology/approach-The results of 29 in-depth interviews (IDIs) with representatives of the key groups of bio-packaging supply chains' (SCs') stakeholders were the input for the consideration of the research problem. Findings-The main economic, legal, social and technological enablers and barriers to the bio-packaging regime transition are recognised, and their impact at the market level is explained. The authors recognised the hybrid transition scenario towards an increase in the market share of compostable packaging related to the three traditional pathways of transformation, reconfiguration and technological substitution. Originality/value-This study contributes to a better understanding of the socio-technical system theory by examining interdependencies between landscape (external environment), market regime (bio-packaging market) and niche innovations (compostable packaging) as well as system transition pathways. The findings and conclusions on bio-packaging market developments can be important lessons learnt to be applied in different countries due to the same current development stage of the compostable packaging lifecycle worldwide.
Biodegradable biobased polymers derived from biomass (such as plant, animal, marine, or forestry material) show promise in replacing conventional petrochemical polymers. Research and development have been conducted for decades on potential biodegradable biobased polymers such as polylactic acid (PLA), polyhydroxyalkanoates (PHAs), and succinate polymers. These materials have been evaluated for practicality, cost, and production capabilities as limiting factors in commercialization; however, challenges, such as the environmental limitations on the biodegradation rates for biodegradable biobased polymer, need to be addressed. This review provides a history and overview of the current development in the synthesis process and properties of biodegradable biobased polymers, along with a techno-commercial analysis and discussion on the environmental impacts of biodegradable biobased polymers. Specifically, the techno-commercial analysis focuses on the commercial potential, financial assessment, and life-cycle assessment of these materials, as well as government initiatives to facilitate the transition towards biodegradable biobased polymers. Lastly, the environmental assessment focuses on the current challenges with biodegradation and methods of improving the recycling process and reusability of biodegradable biobased polymers.
This study presents the synthesis of agro-waste banana peel extract-based magnetic iron oxide nanoparticles (BPEx-MIONPs), emphasizing antioxidant capacity and food preservation. Using iron (III) chloride hexahydrate (FeCl3 · 6 H2O) as a precursor and a reducing agent from agro-waste peel extract, a precisely controlled process yielded BPEx-MIONPs. Characterization involved X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy (FTIR). XRD revealed tetragonal Fe2O3, cubic magnetite structure, and monoclinic FexOy-NPs with an average size of 14.8 nm. TEM and SEM revealed diverse morphologies. TEM displayed both spherical and elongated nanoparticles, with some appearing as thin fibrils. In contrast, SEM images depicted an array primarily consisting of spherical nanoparticles, resembling coral reef formations. FTIR confirmed Fe–O bonds (1000 –400 cm⁻¹). The antioxidant assessment showed robust DPPH free radical scavenging; BPEx achieved 100% inhibition at 18 min, and BPEx-MIONPs had an IC50 of ~ 136 µg/mL. BPEx-MIONPs, stabilized with banana-based bioplastic, effectively preserved grapes, reducing weight loss to 6.2% on day 3, compared to the control (19.0%). This pioneering study combines banana peel antioxidants with magnetic iron oxide nanoparticles, providing sustainable solutions for food preservation and nano-packaging. Ongoing research aims to refine conditions and explore broader applications of BPEx-MIONPs.
Graphical Abstract
Biobased nanomaterials have garnered increasing attention in recent years due to their potential for reducing the environmental impact of materials. To ensure that these materials are sustainable and biodegradable, it is important to consider both their biodegradability and sustainability. Biodegradability refers to the ability of a material to be broken down into simpler, nontoxic substances, while sustainability refers to the ability of a material to be produced and used in a way that does not harm the environment. Biobased nanomaterials have the potential to be more sustainable than traditional materials because they can be derived from renewable sources and have a lower carbon footprint. However, it is important to consider the entire life cycle of the material to ensure its sustainability. Researchers are exploring various strategies for promoting the biodegradability and sustainability of biobased nanomaterials, such as using biodegradable polymers or designing materials that can be broken down by specific enzymes. Overall, it is important to continue developing and promoting sustainable and biodegradable biobased nanomaterials to reduce the environmental impact of materials and promote a more sustainable future.
Life cycle assessment (LCA) is a quantifiable strategy in which every phase of the life of manufactured goods is investigated and analysed for multiple impact categories with environmental impact worth, such as ozone layer depletion, ecotoxicity, climate change, and water and resource depletion. When humans utilise biological, chemical, or physical procedures to transform raw materials into finished goods with anticipated attributes, they generate environmental impacts known as emissions as a by-product. The outcomes of LCA research should be prudently evaluated since particular difficulties are involved in creating an LCA for biobased products. There are three methods for evaluating a product’s life cycle: cradle-to-gate, cradle-to-cradle, and cradle-to-grave. These three evaluation models, the LCAs structure, the many phases of the life cycle, and the frameworks for evaluating biobased products are all covered in this chapter.
Background, aim, and scope: Worldwide, the production of biodegradable and compostable plastics has steadily grown. In Part 1 (Khoo et al. 2010), life cycle assessment (LCA) was applied to compare the production stages of a bio-based bag (made from polyhydroxyalkanoate or bio-plastic (PHA)) with polyethylene plastic bag. The scope of the study is within the context of Singapore and does not include other types of conventional or bio-based polymers (e.g., polylactic acid (PLA), thermoplastics, high-density polyethylene (HDPE), EPS, etc). This article (part 2) proposes to investigate the end-of-life options of both bags. Materials and methods: For part 2, the same LCA methodology is used for the investigation. The LCA system for part 2 starts with disposal options: (1) land filling at Singapore's offshore Semakau Island, (2) incineration, and the (3) composting of bio-bag. Two useful products, energy and compost, will be produced from options 2 and 3, respectively. While the energy from the incineration of both bags are fed back into the LCA production stage, compost from bio-bags can be used as a peat substitute, thus generating carbon dioxide savings from reduced peat production. The end-of-life environmental impacts were generated for global warming potential, acidification, and photochemical ozone formation. A landfill impact, based on Singapore's offshore landfill capacity, was also generated. Next, the environmental impacts of the entire life cycle of both products are calculated for a few scenarios-from cradle-to-grave. Results: The highest end-of-life impacts are observed from the land filling of bio-bags. Next highest disposal impacts are from incineration, and least of all (minimal) from the composting of bio-bags. The greenhouse gas savings from peat substitutes derived from the compost material is rather insignificant. Overall, the cradle-to-grave results demonstrates that the environmental burdens generated from any of the disposal options are less significant compared to those from both products' life cycle production stages. Discussion and conclusions: Unless plans for energy recovery systems are in place, the least preferred route for the disposal of bio-bags are at landfills. From the trend of the final cradle-to-grave results, it can be claimed that the life cycle production of bio-bags from PHA can only be considered as environmentally friendly alternatives to conventional plastic bags if clean energy sources are supplied throughout its production processes. This claim was in agreement with other LCA work carried out for the life cycle production of PHA, with the supply of energy by corn stover waste or the consideration of wind power supply in the replacement of grid electricity. It was also observed, however, that some of the results in this article vary from other LCA work carried out by other authors. Some of the reasons included variations in LCA scope and the different range of materials investigated (PLA, HDPE, and thermoplastic starch). Recommendations and perspectives: Presently, the wide range of LCA work carried out on biodegradable polymers differs considerably in the amount of reported background data and the level of detail concerning the LCA system and production methods. A globally accepted as well as concerted effort to describe in detail the life cycle production steps involved, disposal options, type of energy supplied to the production chain, for a well-selected range of polymer materials should be conducted. Meanwhile, it is recommended that a conservative approach is required in introducing bio-based carrier bags as a solution for solving plastic waste issues. Future LCA investigations should also look into the reuse of carrier bags, which is anticipated to bring much greater environmental and sustainable benefit than the replacement of bio-bags with plastic ones.
Recent years have seen an upsurge of interest in life cycle assessment (LCA) as a tool for evaluation of pote ntial environmental impacts of any industrial activity. It is often found that the main environmental impact is generated from electricity consumed, e.g., during manufacturing and usage stage of industrial products. In Japan, 10 electric companies supply electricity to the entire region. Therefore, in this study, the life cycle inventories for the 10 electricity companies in Japan were developed based on fiscal year 2002 data. The life cycle emissions were estimated for the systems using a combination of proces s analysis and input-output analysis. For the life cycle impact assessment (LCIA) method, the proposed LCA consolidated evaluation technique called LCA-NETS (Numerical Eco-load Total Standard) method is used. As the result, the LCA evaluations are discussed for further ecological improvement.
We developed a new emission inventory for Asia (Regional Emission inventory in ASia (REAS) Version 1.1) for the period 1980-2020. REAS is the first inventory to integrate historical, present, and future emissions in Asia on the basis of a consistent methodology. We present here emissions in 2000, historical emissions for 1980-2003, and projected emissions for 2010 and 2020 of SO2, NOx, CO, NMVOC, black carbon (BC), and organic carbon (OC) from fuel combustion and industrial sources. Total energy consumption in Asia more than doubled between 1980 and 2003, causing a rapid growth in Asian emissions, by 28% for BC, 30% for OC, 64% for CO, 108% for NMVOC, 119% for SO2, and 176% for NOx. In particular, Chinese NOx emissions showed a marked increase of 280% over 1980 levels, and growth in emissions since 2000 has been extremely high. These increases in China were mainly caused by increases in coal combustion in the power plants and industrial sectors. NMVOC emissions also rapidly increased because of growth in the use of automobiles, solvents, and paints. By contrast, BC, OC, and CO emissions in China showed decreasing trends from 1996 to 2000 because of a reduction in the use of biofuels and coal in the domestic and industry sectors. However, since 2000, Chinese emissions of these species have begun to increase. Thus, the emissions of air pollutants in Asian countries (especially China) showed large temporal variations from 1980-2003. Future emissions in 2010 and 2020 in Asian countries were projected by emission scenarios and from emissions in 2000. For China, we developed three emission scenarios: PSC (policy success case), REF (reference case), and PFC (policy failure case). In the 2020 REF scenario, Asian total emissions of SO2, NOx, and NMVOC were projected to increase substantially by 22%, 44%, and 99%, respectively, over 2000 levels. The 2020 REF scenario showed a modest increase in CO (12%), a lesser increase in BC (1%), and a slight decrease in OC (-5%) compared with 2000 levels. However, it should be noted that Asian total emissions are strongly influenced by the emission scenarios for China.
The first edition described the concept of Integrated Waste Management (IWM), and the use of Life Cycle Inventory (LCI) to provide a way to assess the environmental and economic performance of solid waste systems. Actual examples of IWM systems and published accounts of LCI models for solid waste are now appearing in the literature. To draw out the lessons learned from these experiences a significant part of this 2nd edition focuses on case studies - both of IWM systems, and of where LCI has been used to assess such systems. The 2nd edition also includes updated chapters on waste generation, waste collection, central sorting, biological treatment, thermal treatment, landfill and materials recycling. This 2nd edition also provides a more user-friendly model (IWM-2) for waste managers. To make it more widely accessible, this edition provides the new tool in Windows format, with greatly improved input and output features, and the ability to compare different scenarios. A detailed user's guide is provided, to take the reader through the use of the IWM-2 model, step by step. IWM-2 is designed to be an "entry level" LCI model for solid waste - user-friendly and appropriate to users starting to apply life cycle thinking to waste systems - while more expert users will also find many of the advanced features of the IWM-2 model helpful. IWM-2 is delivered on CD inside the book. © 2001 Procter & Gamble Technical Centres Limited. All rights reserved.
Natural gas is used for steam and heat production in industrial processes, residential and commercial heating, and electric power generation. Because of its importance in the power mix, a life cycle assessment on electricity generation via a natural gas combined cycle system has been performed.
This report presents the findings from a study of the life cycle inventories for petroleum diesel and biodiesel. It presents information on raw materials extracted from the environment, energy resources consumed, and air, water, and solid waste emissions generated. Biodiesel is a renewable diesel fuel substitute. It can be made from a variety of natural oils and fats. Biodiesel is made by chemically combining any natural oil or fat with an alcohol such as methanol or ethanol. Methanol has been the most commonly used alcohol in the commercial production of biodiesel. In Europe, biodiesel is widely available in both its neat form (100% biodiesel, also known as B1OO) and in blends with petroleum diesel. European biodiesel is made predominantly from rapeseed oil (a cousin of canola oil). In the United States, initial interest in producing and using biodiesel has focused on the use of soybean oil as the primary feedstock mainly because the United States is the largest producer of soybean oil in the world. 170 figs., 148 tabs.