Package Research Articles

Opportunities for plain packaging of tobacco products in the Philippines: results of a nationwide online survey.

This study aimed to contribute to local research evidence to promote the implementation of plain packaging of tobacco products in the Philippines. The study aimed to assess Filipinos' perception of the effectiveness of plain packaging and their readiness by assessing the potential impact of plain packaging. We conducted a nationwide geographically representative online panel survey with a sample size of 2,000 Filipinos. The survey recruited respondents 18-65 years old and residing in the Philippines, with 500 respondents each from the National Capital Region, Luzon, Visayas, and Mindanao. We showed respondents six different mock-ups of cigarette packs in plain packaging, with two sizes of graphic health warnings (50 and 75%) and three plain packaging colors (black, white, and Pantone 448C). Using five-point Likert scales, participants rated their agreement with 18 items assessing readiness and rationales for plain packaging and 54 items related to pack design (9 items for 6 pack designs). The study showed that Filipinos recognize the value of adopting plain packaging with larger graphic health warning labels on tobacco products in the Philippines. Both non-smokers and smokers agreed that plain packaging has the potential to reduce the attractiveness and appeal of packs, prevent advertisement and promotion of tobacco products, reduce the ability of tobacco products to mislead consumers, increase the noticeability and effectiveness of the pictorial health warnings, increase recall of the pictorial health warnings, affect consumer perceptions of the attractiveness of the tobacco products and their relative safety, reduce youth experimentation with the use of tobacco products, prevent the use of tobacco brand variants as a promotional tool, prevent branding targeted toward youth, promote quitting among current users, and to more clearly inform consumers about the harmful effects of tobacco use. We recommend that policymakers pursue plain packaging as legislation or as part of a reform of the Philippines' graphic health warnings law. The law should target tobacco products sold in the Philippines.

Synthetic Microplastics in UK tap and bottled water; Implications for human exposure

There is increasing concern for public health over inadvertent human exposure to MPs due to potential adverse health effects linked to MPs polymeric composition, toxic chemical additives, and/or harmful microorganisms adsorbing onto their surfaces. While numerous studies have reported MPs occurrence and risk in the freshwater aquatic environment and drinking water sources (e.g., rivers, lakes, and reservoirs), the current state-of-knowledge on MPs pollution in drinking water (i.e., tap water and bottled water) remains limited at a global level. This paper provides the first comprehensive study of the occurrence, concentrations, size distribution, shape, and polymer type of MPs in 177 tap water samples from 13 cities in the United Kingdom, as well as 85 samples of bottled water from 17 popular brands, with various packaging materials, on the UK market.MPs were detected in all tap water samples (range 6–100 MP/L) and bottled water samples (range 12–62 MP/L). Average MPs concentration in tap water (40 ± 16 MP/L) was statistically indistinguishable from that in bottled water (37 ± 11 MP/L). However, the average MPs particle size in tap water (32.4 μm) exceeded significantly (p < 0.05) that in bottled water (26.5 μm), indicating the various purification processes applied to bottled water may help remove larger MPs, but raises concern over the potential adverse health effects from exposure to smaller MPs. The most frequently detected polymer types were: polypropylene (PP), polyethylene (PE), and polyvinyl chloride (PVC) in tap water, and PE, PP and polyethylene terephthalate (PET) in bottled water. A strong correlation was observed (r = 0.68, P = 0.049) between the plastic cap material (PE) and the predominant polymer type in the bottled water. In terms of morphology, fragments and fibres were the most abundant MPs, together constituting 92 % and 96 % of MPs detected in tap and bottled water samples, respectively.Using EFSA (European Food Safety Authority) recommended daily water intakes, the corresponding exposures to MPs in different UK age groups were estimated. On a body weight (BW) basis, infants and toddlers were exposed (4 MP/kg BW/day) at a higher level than adults (1 MP/kg BW/day). This raises concern, given the former's incompletely developed immune/nervous systems rendering them at higher risk of adverse health effects from such exposure.

Waste-based composites using post-industrial textile waste and packaging waste from the textile manufacturing industry for non-structural applications

The textile industry significantly contributes to environmental pollution, generating substantial amounts of waste. The prevailing linear model exacerbates this issue, accumulating a significant portion of the waste in landfills. This research aimed to tackle these challenges by developing value-added composites from post-industrial textile waste and packaging materials, for non-structural building applications. To achieve this, shredded polyester textile waste fibers served as the reinforcement, while waste packaging was used as the matrix. Varying fiber-matrix weight percentages seven composite types were developed. The physical, mechanical, and thermal properties of the composites were evaluated. The findings indicated that these composites exhibited properties comparable to those of commercial partition boards. Notably, composites with fiber weight percentages of 7.5 % and 10 % demonstrated the most favorable performance among the tested variations. Emphasizing the application of sustainable chemistry, this study highlights the potential of these composites to develop substitute materials for non-structural building applications. Moreover, it presents a promising solution to address the textile waste management challenge and value-added materials for the construction industry in a developing context.

4D printing of polylactic acid (PLA)/PLA-thermoplastic polyurethane (TPU)-based metastructure: examining the mechanical, thermal, and shape memory properties

Abstract In the present day and age, increasing demand concerning the enhancement of the mechanical performance of Shape Memory Polymer (SMP) based structures has paved the way for developing newer metastructures of enhanced load-bearing, damping capacity, and durability. The present study focuses on developing SMP-based metastructures made of commercially available Polylactic Acid (PLA) and 30% by wt. of Thermoplastic Polyurethane (TPU) blended PLA. The designed metastructures are initially analyzed using numerical modeling to prevent lateral deformation, acute stress concentration zones, and row-wise collapse. Mechanical tests reveal that blending TPU with PLA enhances the material's flexibility and ductility, further improving the toughness and fracture resistance of the built metastructures. Loading-unloading and shape recovery tests (under compression mode) of the s-shape metastructure reveal that the PLA/TPU metastructure withstands ≅ 170 N load, less than neat PLA's ≅ 223 N due to TPU's flexibility. PLA/TPU endures 30 cycles, while PLA fails after the 9th cycle. In shape recovery plots, PLA/TPU metastructures exhibit a lower standard deviation (~0.32%) than PLA (~1.4%), attributed to the entropy decrease and cross-linkage disentanglements of PLA. Furthermore, a Dynamic Mechanical Analyzer (DMA) assesses glass transition temperature, energy storage capability, and dissipation in variation with the temperature. The nephograms of ABAQUS result divulge accurate fracture initiation locations of the metastructure unit cells, which involves implementing ductile damage behavior modeling by employing damage initiation and evolution parameters. Finally, assessing compression tests and shape recovery behavior results elucidates that these SMP-based metastructures are promising for load-bearing pallets in the transporting and packaging industries, providing superior damping and self-repairing capabilities during significant plastic deformations.

Selection of optimal polymer joining technology: Insights and decision support through interrelated case studies using CARCACS method

Polymer materials play an essential role in the automotive, aerospace, packaging, and healthcare industries, necessitating reliable joining processes to ensure structural integrity, functionality, and cost efficiency. Choosing the optimal polymer joining technology involves evaluating various criteria, such as design freedom, investment, joint quality, process adaptability, cycle time, etc., for prioritization and informed decision-making. This study aims to systematically assess polymer joining processes to improve efficiency and sustainability in industrial applications. Two interrelated case studies are conducted using the CARCACS (“Criteria-wise Alternative Ranking and Correlation Analysis for Composite Scoring”) method. The first case study identifies laser transmission welding as the most suitable joining process among eight commonly used processes based on multiple evaluation criteria. The second case study refines this selection by examining various laser welding systems, with fibre lasers emerging as the optimal choice. Validation through comparison with other MCDM (Multi-Criteria Decision-Making) methods and Spearman's rank correlation coefficients reveals strong agreement and robust decision-making. Sensitivity analysis further confirms the stability of the top-ranked alternatives across different scenarios. This research provides a robust framework for selecting polymer joining technologies and demonstrates the practical implications for optimizing these technologies in industrial applications.

Antioxidant packaging films based upon starch-montmorillonite with forsythia flower extract: characterization and application

Plastic pollution is one of the most acute environmental problems in the world, so active packaging materials made from biodegradable natural polymers have received widespread attention in recent years. In this paper, forsythia flower extract, serving as an active ingredient, was integrated into the starch-sodium alginate-montmorillonite composite film. The physicochemical properties and functional packaging applications of the composite films were investigated. The results demonstrate the formation of a tightly-knit network structure through molecular interactions among forsythia flowers, starch, sodium alginate, and montmorillonite. Notably, the addition of forsythia flower extracts conferred better UV resistance (from 200 nm to 400 nm) and outstanding antioxidant properties to the composite films. After 18 days of storage, in comparison with the control group, the decay rate of fresh cherry tomatoes packaged with the composite film containing forsythia flower extract showed a significant reduction of 40%, the hardness increased by 25%, and the content of vitamin C was enhanced by 33%. Hence, the forsythia flower extract composite film offers a novel perspective for the design and development of bio-based packaging films for preserving fresh fruits. The results serve as a foundation for the subsequent advancement and application of forsythia flower in the field of packaging.

Multifunctional honeysuckle extract/attapulgite/chitosan composite films containing natural carbon dots for intelligent food packaging

In order to fulfill people's requirements for food quality and safety, it is a promising strategy to develop intelligent biodegradable food packaging materials. Herein, honeysuckle extracts/attapulgite/chitosan composite films containing natural carbon dots were fabricated for intelligent food packaging. Different characterization techniques were employed to study the obtained composite films, while the physicochemical properties, optical properties, antibacterial and antioxidant activities of composite films were determined. The obtained composite films presented good mechanical, antibacterial and antioxidant properties, and the antibacterial ratios of composite films against Escherichia coli and Staphylococcus aureus were 99.27 ± 0.18 % and 98.85 ± 0.65 %, respectively. When the added amount of honeysuckle extracts/attapulgite nanocomposites was 4.76 %, the tensile strength and elongation at break of composite films reached 24.9 ± 2.35 MPa and 64.8 ± 2.11 %, respectively, which were obviously higher than that of pure chitosan film. Furthermore, the composite films exhibited excellent UV shielding and blue fluorescence properties, as well as pH-sensitivity due to the presence of caffeoquinic acid-based natural carbon dots derived from honeysuckle extract. Therefore, the composite films indicated a potential application for intelligent food packaging.

Effect of different packaging materials on banana ripening and shelf-life in Dang, Nepal

This research was conducted to evaluate the effect of different packaging materials on the shelf life and banana quality (cv G9) at the laboratory, Campus of Live Sciences, Tulsipur, Dang, Nepal. The different packaging materials were used as high-density non-perforated polyethylene bags, low-density non-perforated polyethylene bags, low-density perforated polyethylene bags, fiber bags, jute bags, paddy straw with cardboard, and a control treatment (in open trays). The research was conducted in a completely randomized design (CRD) with three replications. The bananas were packed in different packaging materials after being treated with a 250 ppm ethephon solution. Parameters such as peel color, physiological weight loss, pulp-to-peel ratio, total soluble solids (TSS), titratable acidity (TA), and Benedict test were assessed at two-day interval. Analysis of variance (ANOVA) showed highly significant differences for all the recorded parameters except TA. Unpackaged fruits lost 22.92% of their weight, while fruits packed in high-density non-perforated polythene (HDNP) and low-density non-perforated polythene (LDNP) bags lost 13.27% and 6.15%, respectively. Peel colour development from green mature to yellow was observed first in bananas packed in low-density perforated polyethylene (LDPP) bags followed by open trays, jute bags, and paddy straws. The lowest pulp-to-peel ratio was observed in HDNP and LDNP bags. It can be concluded that packaging bananas in high-density and low-density non-perforated polyethylene bags resulted in longer shelf life. The sweetness, aroma, and mouthfeel of bananas in jute bags, fiber bags, and paddy straws were highly accepted. Thus, LDPP bags were found effective in early ripening and uniform yellow colour development on bananas.

Delamination and Evaluation of Multilayer PE/Al/PET Packaging Waste Separated Using a Hydrophobic Deep Eutectic Solvent.

This research concerns the development and implementation of ground-breaking strategies for improving the sorting, separation, and recycling of common flexible laminate packaging materials. Such packaging laminates incorporate different functional materials in order to achieve the desired mechanical performance and barrier properties. Common components include poly(ethylene) (PE), poly(propylene) (PP), and poly(ethylene terephthalate) (PET), as well as valuable barrier materials such as poly(vinyl alcohol) (PVOH) and aluminium (Al) foils. Although widely used for the protection and preservation of food produce, such packaging materials present significant challenges for established recycling infrastructure and, therefore, to our future ambitions for a circular economy. Experience from the field of ionic liquids (ILs) and deep eutectic solvents (DESs) has been leveraged to develop novel green solvent systems that delaminate multilayer packaging materials to facilitate the separation and recovery of high-purity commodity plastics and aluminium. This research focuses on the development of a hydrophobic DES and the application of a Design of Experiments (DoE) methodology to investigate the effects of process parameters on the delamination of PE/Al/PET laminate packaging films. Key variables including temperature, time, loading, flake size, and perforations were assessed at laboratory scale using a 1 L filter reactor vessel. The results demonstrate that efficient separation of PE, Al, and PET can be achieved with high yields for material and solvent recovery. Recovered plastic films were subsequently characterised via Fourier-transform infra-red (FTIR) spectroscopy, Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA) to qualify the quality of plastics for reuse.

Pemberdayaan Ekonomi Pesantren melalui One Pesantren One Product (OPOP) di Ponpes Kawasan Pantura Lamongan

The Covid pandemic has had a huge impact on Indonesia's Economy. UMKM boarding school was adversely affected. OPOP becomes one of the beneficial ways to revive this situation. Unfortunately, many boarding schools in East Java still have no experience joining OPOP. Hence, this Madrasah and Pesantren-based program urgently needs to be conducted. The accompaniment aims to optimize three boarding schools' products and economic potential on the North Coast of Lamongan. They are Maslakul Huda, Mazraatul Ulum, and Raudlatut Thullab boarding schools. This program applies the ABCD method and appreciative inquiry approach. The result signifies that all students, alums, and the boarding school can synergize more optimally to establish better financial management, marketing, and packaging products and enhance the understanding of benefits, strategy, and OPOP membership. In short, they perceive the accurate way to thoroughly improve their economic potential to realize a more empowered boarding school and prosperous society.

Preparation of chitosan/polyvinyl alcohol antibacterial indicator composite film loaded with AgNPs and purple sweet potato anthocyanins and its application in strawberry preservation

This study incorporated purple sweet potato anthocyanin (PSPA) and silver-nanoparticles (AgNPs) into the chitosan/polyvinyl alcohol film matrix (PVA/CS) to successfully prepare a composite film, which effectively inhibited bacterial growth and indicated product freshness. The addition of AgNPs and PSPA led to a dense structure of the film, which effectively enhanced its physical properties, barrier properties and functional properties. The incorporation of PSPA made the composite film highly pH-sensitive, which exhibited distinct color changes in varying pH solutions. The PVA/CS-AgNPs-PSPA10 composite film with PSPA and AgNPs resulted the shelf life of strawberries to 13 days at 4 °C, which effectively reduced strawberry breathing during storage. Additionally, such composite film changed color from purple to yellow-purple, indicating the deterioration of strawberries. It also showed an antibacterial indication through its excellent antibacterial property and freshness indication performance, which demonstrated its significance in developing antibacterial indicator composite packaging materials for fruits and vegetables preservation.

Development and Validation of an ICP‐OES Method to Determine Extractable and Leachable Metals in HDPE (Plastic) Pharmaceutical Packaging Material

ABSTRACTThe safety and effectiveness of pharmaceutical medicines depend heavily on extractables and leachables. Patients may be adversely affected by contaminants that enter drug products through packing materials. As a result, regulatory organizations like the European Medicines Agency (EMA) and the US Food and Drug Administration (FDA) have set standards and regulations for evaluating and managing extractables and leachables. Characterizing the packing materials, carrying out extraction experiments and checking the extracted solutions for contaminants are all parts of this research. As part of the process for approving new drugs, regulatory agencies make use of these data. In present work, an inductively coupled plasma optical emission spectroscopy (ICP‐OES) method is developed and validated for quantifying trace elements from a high‐density polyethylene (HDPE) packaging material. The approach delineated in accordance with United States Pharmacopoeia (USP) &lt;661.1&gt; and &lt;661.2&gt; for the comprehensive analysis of 16 metallic elements including aluminium, arsenic, cadmium, chromium, cobalt, lead, mercury, nickel, titanium, vanadium, zinc, zirconium, barium, manganese, calcium and tin is applicable for evaluating the efficacy of packaging materials. The method detection limits (MDLs) complied as per USP 39‐NF 34 &lt;661.1&gt; along with relative standard deviations (RSDs) obtained were ranging from 0.3% to 3.1% and recoveries of all elements spiked at two different trace levels in HDPE samples were within 97%–110%, providing sensitive, accurate and reproducible methodology.

Utilizing Flax Straw for Sustainable Paper Production: Delignification Methods, Structural Analysis, and Fiber Size Distribution Effects

This research explores the potential of agricultural waste, specifically flax straw, as a sustainable raw material for eco-friendly packaging materials. This study investigates a three-stage delignification process involving nitric acid, alkaline treatment, and organosolvent solutions. This method effectively removes lignin from the straw, resulting in high-quality technical pulp with 67.7% α-cellulose and a significantly reduced ash content (8.5%). X-ray diffraction (XRD) and thermogravimetric analysis (TGA) were employed to characterize the treated flax straw. XRD analysis revealed changes in the cellulose structure, while TGA indicated enhanced thermal stability compared to untreated straw. Microscopic analysis of the pulp fibers shows a parallel and aligned arrangement, suggesting a high fiber content and a strong paper lattice. The particle size distribution of the ground pulp, influenced by fiber size, has implications for the packing density and mechanical properties of the final product. This study demonstrates the potential of agricultural waste as a sustainable source for packaging materials, contributing to the circular economy and waste reduction.

Review of Bio-Based Biodegradable Polymers: Smart Solutions for Sustainable Food Packaging.

Conventional passive packaging plays a crucial role in food manufacturing by protecting foods from various external influences. Most packaging materials are polymer-based plastics derived from fossil carbon sources, which are favored for their versatility, aesthetic appeal, and cost-effectiveness. However, the extensive use of these materials poses significant environmental challenges due to their fossil-based origins and persistence in the environment. Global plastic consumption for packaging is expected to nearly triple by 2060, exacerbating the ecological crisis. Moreover, globalization has increased access to a diverse range of foods from around the world, heightening the importance of packaging in providing healthier and safer foods with extended shelf life. In response to these challenges, there is a growing shift to eco-friendly active packaging that not only protects but also preserves the authentic qualities of food, surpassing the roles of conventional passive packaging. This article provides a comprehensive review on the viability, benefits, and challenges of implementing bio-based biodegradable polymers in active food packaging, with the dual goals of environmental sustainability and extending food shelf life.

Spider web-reinforced chitosan/starch biopolymer for active biodegradable food packaging

In this study, starch (ST), chitosan (CH), spider silk (SW), and their hybrid composite bioplastics were fabricated and examined for physicochemical and mechanical properties. The essential oils (EOs) of Rosmarinus officinalis were encapsulated to enhance their biological application. The prepared composite films were characterized using various spectroscopic techniques such as XRD, SEM, GCMS–, UV–VIS, TGA, and FTIR spectroscopy. The antimicrobial activity of the prepared film was tested against S. aureus bacterial and C. albican fungal strains which showed a greater zone of inhibition for the composite film encapsulated with EOs. The biodegradability of the synthesized film was evaluated for 60 days in soil under laboratory conditions. The composite film containing spider web and essential oil significantly improved mechanical properties. The physicochemical results, such as moisture, solubility, swelling, transmittance, opacity, and water vapor permeability, of the prepared bioplastic were comparable with those of the control plastic. The EO-based film had greater antioxidant activity against DPPH, hydrogen peroxide, and phosphomolybdenum assays, with an inhibition range of 60–70 %. The addition of spider web and essential oil to the chitosan/ starch film significantly increased the shelf life of injera and tomatoes for 7 and 10 days, respectively for the EO-based film. The biodegradability of the synthesized film has shown a great reduction in the weight and growth of microorganisms. In general, the CH/ST/SW and CH/ST/SW/EOs composite films have greater mechanical, biological, physicochemical, and potential improvement of food shelf life applied as either coating or packaging material.

Endothermic–Exothermic Hybrid Foaming of Recycled PET Blends

Over the past decades, the use of polyethylene terephthalate (PET) has seen significant growth, particularly in the packaging industry. However, its long decomposition time poses serious environmental challenges. The aim of this research was to develop a process for the foaming of large quantities of recycled PET (rPET) using endothermic and exothermic foaming agents. Various formulations with different ratios of endothermic and exothermic foaming agents were prepared, as well as their mixtures. The study found that the endothermic–exothermic hybrid foaming process resulted in a finer cell-size distribution and enhanced mechanical properties, making the foams highly suitable for widespread applications. The results support the potential use of exothermic foaming agents as nucleating agents in a hybrid foaming system. In particular, the ratio of 3% endothermic and 1% exothermic foaming agents proved optimal in terms of achieving a balance between porosity and mechanical strength, thereby enabling broad industrial applicability.

Preparation of biomass fiber/polylactic acid foam using an oven-type free foaming method for energy savings and performance enhancement

Given the inherent challenges of low melt strength and slow crystallization rate associated with polylactic acid (PLA), this study introduces a sustainable and efficacious approach to enhance PLA crystallization utilizing biomass tomato peel pomace powder (TP) as a heterogeneous nucleating agent. ZnO-modified azodicarbonamide (ADC) was used as the chemical blowing agent. The blends were prepared with the aid of a torque rheometer, and TP/PLA composite foams were successfully prepared by the oven-type free foaming method. The empirical results demonstrate that the TP/PLA composite foam exhibits reduced processing requirements and superior comprehensive properties compared to pure PLA foam. Specifically, the composite containing 5 wt% TP achieved optimal foaming performance with 3 phr blowing agents and a foaming duration of 10 min. Furthermore, the annealing treatment markedly enhanced the compression modulus and strength of the foams. Under annealing conditions of 110 °C for 30 min, the compressive strength of the foam increased by 483.5 % relative to the untreated sample. The development of this composite foam signifies a novel direction for energy-efficient performance enhancement and holds significant potential for applications in building insulation and packaging industries.

Selection Results of Solid Material for Horizontal and Highly-Deviated Well Completion Gravel-Packing: Experiments, Numerical Simulation and Proposal

Lightweight and ultra-lightweight solid materials are being used in gravel packing for horizontal wells instead of traditional quartz and ceramsite to decrease the risk of premature plugging and improve packing efficiency. Physical and numerical simulation experiments of gravel packing were conducted to assess the effectiveness of reducing solid material density and investigate its impact on packing and sand control. Packed gravel destabilization experiments highlighted the importance of high-compaction degree packing for effective sand control. Further gravel packing experiments examined the packing performance of different solid materials, revealing that lightweight solids have minimal gravitational deposition effect because their density is similar to the gravel slurry, relying primarily on fluid flow for compaction. The numerical simulation indicated that lightweight ceramsite is unsuitable for horizontal and highly-deviated wells because of its poor compaction degree and sand control, especially with high-viscosity slurry. High-density particles enhance gravitational deposition, improving packing compaction and sand control. Lightweight materials are recommended only when advanced plugging of α wave packing cannot be avoided. In highly-deviated wells, high-density materials significantly improve packing stability and sand control. This study provides clear technical guidelines for selecting solid materials for gravel packing in horizontal and highly-deviated wells.

The influence of Multi-Layer Plastic Packaging (MPP) on the high-temperature performance of asphalt binders and mixtures using wet and dry mixing methods

ABSTRACT High temperatures, combined with heavy traffic loads, increase the risk of permanent deformation and reduce the useful lifespan of pavements, leading to a greater need for maintenance and rehabilitation activities throughout the pavement's service life. This study aims to evaluate the effectiveness of recycled thermoplastic additives, specifically Multi-Layer Plastic Packaging (MPP) materials, in enhancing the high-temperature performance of asphalt mixtures. MPP materials, including types such as Polyester, Polyethylene, Nylon, and Metalized Polyester, were used for binder modification in asphalt mixtures. The modification was conducted using both wet and dry methods. The physical and rheological properties of the modified binders were assessed at high temperatures to determine their impact on stiffness and resistance to permanent deformation. The results indicate that MPP materials significantly improve the high-temperature performance of asphalt mixtures by enhancing binder stiffness and resistance to permanent deformation, with the wet method proving more effective than the dry method. These findings highlight the need for developing practical guidelines for incorporating MPP materials in asphalt production in the future and underscore the importance of comprehensive studies on maintenance, rehabilitation, and overall pavement lifecycle costs.

Characteristics, drivers and ecological risk assessment of microplastics in the surface water of urban rivers in Guangdong-Hong Kong-Macao Greater Bay Area cities - A case study of Dongguan city

In the Guangdong-Hong Kong-Macao Greater Bay Area (GBA), microplastic pollution in urban rivers is a prominent problem due to the developed economy and high industrial intensity. Using the Xiaohai River, Hanxi River and Dongguan Canal in Dongguan City, an important node city in the GBA, as an example, microplastic characteristics, drivers and ecological risks in the surface water of three rivers were investigated. Results showed that the average abundance of rivers in the wet period (1646.22 ± 154.73 items/m3) was 4.7 times higher than that in the dry period (351.09 ± 34.2 items/m3). Microplastics were mainly in the form of fragments and fibers, with a size range of 30–500 μm, and appeared transparent with white color. The microplastic polymer types PE, PP, PET and PA accounted for more than 70%. There are large differences in the characteristics of microplastic pollution during different hydrological periods. Redundancy analysis showed that the distribution of plastics, chemical materials, packaging and printing industries along the rivers dominated the differences in microplastic abundance. The electronic information industry contributed most to the composition of microplastic polymer types. The polymer hazard index, pollution load index, and potential ecological risk index for rivers indicate a medium-high risk classification or higher. Therefore, the industrial layout along the urban rivers should be rationalized, the disposal of microplastics in wastewater should be increased, and the use of green plastic products should be promoted. This study provides support for the management of microplastic pollution in urban surface water in the GBA.