Material Cycles and Chemicals: Dynamic Material Flow Analysis of Contaminants in Paper Recycling

Role of quality assessment of the recycled packaging material in determining its safety profile as food contact material

Food packaging waste significantly impacts global environmental changes, prompting the adoption of a green circular economy approach. Recycling packaging waste is a critical element of this strategy. However, it faces challenges related to the quality of recycled materials and concerns about their safety. Thus, this review aimed to highlight different analytical methods alone or in combination to evaluate the quality of the recycled material. Furthermore, the safety and health aspects related to the migration of contaminants and their relevant regulations have also been discussed. An important parameter while selecting an appropriate recycling method is the composition and nature of the recyclate, for instance, HDPE (High-Density Polyethylene), PET (Polyethylene Terephthalate), and PP (Polypropylene) materials can be recycled using mechanical and chemical recycling, however, PVC (Polyvinyl Chloride) and PS (Polystyrene) present challenges during mechanical recycling due to lower molecular weight and complex compositions, thus are often downcycled into lower-grade products. Still, recycled papers can be more problematic than recycled plastics due to the nature of the materials and the impact of recycling. The literature review suggested that three quality properties i.e., presence of low molecular weight compounds, degree of degradation, and composition should be analyzed by using different spectroscopic, thermo-mechanical, and chromatographic techniques to obtain a detailed understanding of recycled material quality. Furthermore, recycling should be done in such a way that the migration of contaminants should be lower than the migratory limits set by the relevant authorities to avoid any toxicological effects.

Increasing the Recycling of PVC Flooring Requires Phthalate Removal for Ensuring Consumers' Safety: A Cross-Checked Substance Flow Analysis of Plasticizers for Switzerland

As our planet grapples with the severe repercussions of plastic pollution, mechanical recycling has been proposed as a potential remedy. However, increasing mechanical recycling may have unintended negative consequences. For example, recycling of PVC flooring containing hazardous plasticizers that were used in the past may lead to continued exposure. Here we propose measures to increase recycling while circumventing adverse health impacts caused by legacy additives. For this, we conduct a dynamic substance flow analysis for Switzerland and the time period from 1950 to 2100, focusing on three plasticizers: di(2-ethylhexyl) phthalate (DEHP), diisononyl phthalate (DiNP), and di(2-ethylhexyl) terephthalate (DEHT). We quantify the uncertainty of results, check their plausibility against measured concentrations in samples representative for the Swiss market, and compare them with modeled substance flows in Germany. Based on the cross-checked model, future average concentrations of DEHP in PVC flooring on the Swiss market are expected to be above the legal limit of 0.1 wt % for several decades if increased recycling rates are implemented without additional measures. Phasing out the potentially concerning DiNP, too, and preventing phthalates from entering recycling would lower their average market concentrations to values below 0.1 wt % and enable increasing recycling rates without compromising product safety. Analogous measures could help achieve this goal across other European countries and product groups.

Waste LCA and the future

Life cycle assessment (LCA) models quantifying the environmental aspects of waste management have become an integral part of waste management decision-making over the last two decades and have provided ample knowledge on both environmental benefits and drawbacks in the way we handle waste. Waste management and LCA modelling of waste management systems will soon be challenged by profound changes necessary in our societies and sectors to meet sustainable development goals. Foreseen changes in energy, material, and nutrient provision will directly and indirectly affect waste management in terms of its operation and goals. This study reflects on anticipated changes in society and industrial sectors and how these changes may affect waste management and LCA modelling of waste management systems in terms of waste input, the modelling of technologies and systems and exchanges of energy, materials, and nutrients, as well as how it may affect impact assessment and the interpretation of results. The study provides practical recommendations for LCA modelling of future waste management systems, which will hopefully lead to robust assessments that can support decision-making in an evolving society subject to great changes.

Washing of residues from the circular economy prior to sustainable landfill: Effects on long-term impacts

Sustainable landfill continues to play a fundamental role in closing the loop of residual materials of the circular economy. The sustainable landfill relies on both pretreatments and in situ treatments to stabilize the residual waste and immobilize the contaminants, achieving the final storage quality (FSQ) within one generation (typically 30 years). The aim of the study was to investigate the efficiency of the waste washing pretreatment in reducing the waste leaching fraction prior to landfilling, and in decreasing the time needed to reach the FSQ. A laboratory scale washing test was performed on three different kinds of residues from municipal solid waste treatment, usually landfilled: residues sieved from separately collected bio-waste (RB); residues sieved from compost (RC); and residues sieved from mixed waste treatment-plastic line (RP). Column landfill simulation tests were performed to predict and compare the landfill long-term emissions of both washed and raw residues. The results revealed that the washing pretreatment significantly reduced the leachable fraction of contaminants, decreasing the time needed to reach the chemical oxygen demand and ammonia FSQ limits. However, RP residue was the only one respecting the FSQ limits within 30 years.

Quality of recycling: Urgent and undefined

Quality of recycling is a concept used by many authors in the scientific literature and the EU legislator. However, a clear definition of what is intended for quality of recycling and a framework for operationalising it is lacking. Most studies, while proposing indicators reflecting quality, leave the concept of quality largely undefined. Such lack of clarity is an obstacle to the conception of robust policies addressing recycling and circular economy. In this article, we review the available studies investigating on recycling quality, synthetize the approaches available and conclude suggesting a way forward for research to operationalise the definition to support circular economy policy measures and monitoring. Essentially, quality is not an on/off criterion. The definition of quality of recycling should consider that quality depends on technical characteristics of the recyclate, which determine if it is adequate (thus functional) for a certain end application or not. Furthermore, it should consider that the recyclate can be used in different end applications over different markets and that can be adequate for substitution of primary resources in certain applications, but less or not in others. At system-wide level, this results in a certain degree of virgin resource substitution. To this end, preserving functionality, i.e. minimising the recyclate loss of functions via functional recycling, is key. Drawing upon studies on waste management, life cycle assessment and resource dissipation, we link the concept of functionality to substitutability of virgin resources and broader suitability in the circular economy, striving to show the linkages between different perspectives.

Costs and benefits of recycling PVC contaminated with the legacy hazardous plasticizer DEHP

Reusing materials is an attractive option for circular economy and can also reduce emissions of greenhouse gases and pollutants. However, recycling raises questions regarding the potential risks to human health or the environment when hazardous legacy chemical additives of materials are also recycled, instead of the recent and less hazardous additives of virgin materials. To address this trade-off, this study developed a model to calculate the total external cost of material supply, considering the health and environmental impacts of all industrial steps (e.g. virgin material production, incineration, and recycling), and the health effects of recycling chemicals present in the material. The model is coupling material flow analysis, life-cycle analysis, and environmental economics to compare different recycling policies. It is applied for all illustrative purposes to soft PVC and DEHP in France. Results show that recycling of materials is in the long-term positive despite the prolongation of the presence of hazardous additives in materials. The time when the recurring environmental benefits of recycling offset the negative impacts on human health of recycling the additives is very sensitive to the health impact of additives. This approach can improve the harmonization between recycling and circular economy policies, and as a framework to confirm the relevance and size treatments to remove additives from materials during recycling.

The multidimensional effects of single-use and packaging plastic strategies on German household waste management

Single-use and packaging plastic (SUPP) strategies are intended to transform the linear make-use-dispose economy of SUPPs into a more circular, resource-efficient one. The aim of this study was to identify optimal SUPP management concepts from a circular-economy-perspective by assessing the effects of different SUPP strategies on household waste management. Data on the generation and management of SUPP-containing household waste in Germany in 2017 were compiled and a material flow model was established. Regulatory SUPP strategies were translated into scenarios (with effects on waste generation and waste composition) and implemented in the material flow model. The effects on material efficiency, waste generation and lower heating values were evaluated and trade-offs between these target dimensions were identified. In Germany in 2017, 32 kg per person and year of SUPP household waste were generated, of which 28 kg per person and year was packaging waste. From a material efficiency perspective, the combination of banning specific non-packaging SUPPs and optimizing source-separation leads to the maximum increase in final recycling rates of SUPPs in household waste, from 38% to 50%. However, in this scenario the amount of SUPP-containing household waste is hardly reduced as compared to the status quo. The trade-offs observed in different waste management target dimensions highlight the importance of understanding the systemic effects of SUPP strategies on waste management in order to identify optimal solutions from a circular-economy-perspective.

Design of a Waste Paper-Derived Chemically 'Reactive' and Durable Functional Material with Tailorable Mechanical Property Following an Ambient and Sustainable Chemical Approach

Controlled tailoring of mechanical property and wettability is important for designing various functional materials. The integration of these characteristics with waste materials is immensely challenging to achieve, however, it can provide sustainable solutions to combat relevant environmental pollutions and other relevant challenges. Here, the strategic conversion of discarded and valueless waste paper into functional products has been introduced following a catalyst-free chemical approach to tailor both the mechanical property and water wettability at ambient conditions for sustainable waste management and controlling the relevant environmental pollution. In the current design, the controlled and appropriate silanization of waste paper allowed to modulate both the a) porosity and b) compressive modulus of the paper-derived sponges. Further, the association of 1,4-conjugate addition reaction between amine and acrylate groups allowed to obtain an unconventional waste paper-derived chemically 'reactive' sponge. The appropriate covalent modification of the residual reactive acrylate groups with selected alkylamines at ambient conditions provided a facile basis to tailor the water wettability from moderate hydrophobicity, adhesive superhydrophobicity to non-adhesive superhydrophobicity. The embedded superhydrophobicity in the waste paper-derived sponge was capable of sustaining large physical deformations, severe physical abrasions, prolonged exposure to harsh aqueous conditions, etc. Further, the waste paper-derived, extremely water-repellent sponges and membranes were successfully extended for proof-of-concept demonstration of a practically relevant outdoor application, where the repetitive remediation of oil spillages has been demonstrated following both selective absorption (25 times) of oils and gravity-driven filtration-based (50 times) separation of oils from oil/water mixtures at different harsh aqueous scenarios.

Dynamic flow and pollution of antimony from polyethylene terephthalate (PET) fibers in China

Antimony (Sb), a regulated contaminant, is added as a catalyst in the process of polyethylene terephthalate (PET) synthesis. Previously, Sb release from PET bottles and films was studied. However, Sb release from PET fibers (the most common form of PET) is limited. Therefore, a network model of material flow for PET fibers in China is developed, and the anthropogenic Sb flow and release entering into the hydrosphere, pedosphere, and atmosphere are studied based on microexperiments and macromodels. To compensate for the uncertainty caused by material flow analysis, Sb pollution in the surrounding areas (the drinking water of nearby residents and sediments of nearby river area) is further explored by combining field investigations and sample analysis. The results are as follows: 1) the manufacture stage of PET fibers is the main source of Sb release (2926 t), followed by the dyeing (2223 t) and weaving (908 t) stages; 2) Sb release (1108 t) from waste PET fibers subjected to landfill disposal is the highest. Sb release (872 t) from discarded fiber waste is second highest. Sb release from PET fibers subjected to mechanical recycling, incineration, and chemical recycling is 784, 284, and 25 t, respectively; and 3) an obvious source-sink relationship is found between anthropogenic Sb in the rivers and sediments and the intensity of the industries. This study suggests that Sb from PET fibers should be properly managed to prevent widespread dispersion in the hydrosphere, pedosphere, and atmosphere.

Bacterial valorization of pulp and paper industry process streams and waste

The pulp and paper industry is a major source of lignocellulose-containing streams. The components of lignocellulose material are lignin, hemicellulose, and cellulose that may be hydrolyzed into their smaller components and used as feedstocks for valorization efforts. Much of this material is contained in underutilized streams and waste products, such as black liquor, pulp and paper sludge, and wastewater. Bacterial fermentation strategies have suitable potential to upgrade lignocellulosic biomass contained in these streams to value-added chemicals. Bacterial conversion allows for a sustainable and economically feasible approach to valorizing these streams, which can bolster and expand applications of the pulp and paper industry. This review discusses the composition of pulp and paper streams, bacterial isolates from process streams that can be used for lignocellulose biotransformations, and technological approaches for improving valorization efforts. KEY POINTS: • Reviews the conversion of pulp and paper industry waste by bacterial isolates. • Metabolic pathways for the breakdown of lignocellulose components. • Methods for isolating bacteria, determining value-added products, and increasing product yields.

New Approach for Recycling Office Waste Paper: An Efficient and Recyclable Material for Oily Wastewater Treatment

Recycling has attracted great attention in academia, because of the economic and environmental benefits to industry. An eco-friendly strategy for recycling office waste paper (WP) was used to sustainedly separate oil-water mixtures. The hydroxyl groups of cellulose endow WP with superlipophilic and superhydrophilic properties in air and superoleophobic features under water. WP could separate various oils from oil-water mixtures, with separation efficiencies exceeding 99%. Importantly, the superhydrophilic WP could separate oil-water mixtures containing HCl, NaOH, and NaCl with separation efficiency above 98.9% for at least 30 cycles. The superoleophobicity of WP was maintained in solutions of different pH values for at least 24 h, suggesting good durability and stability. This green method is renewable, clean, cost-effective, and environmentally friendly. More importantly, the recycled office waste paper not only removes oil from oily wastewater (such as in oil spills) but also realizes the recycling of WP. This method could provide new insights into resource recycling.

Water Cycle and Circular Economy: Developing a Circularity Assessment Framework for Complex Water Systems

Water - the most vital resource, negatively affected by the linear pattern of growth - still tries to find its positioning within the emerging concept of circular economy. Fragmented, sectorial circularity approaches hide the risk of underestimating both the preservation of and impacts to water resources and natural capital. In this study, a game changing circularity assessment framework is developed (i.e. MSWCA). The MSWCA follows a multi-sectoral systems approach, symbiotically managing key water-related socio-economic (i.e. urban water, agro-food, energy, industry and waste handling) and non-economic (i.e. natural environment) sectors. The MSWCA modelling framework enables the investigation of the feedback loops between the nature-managed and human-managed systems to assess water and water-related resources circularity. The three CE principles lie at the core of the developed framework, enabling the consideration of physical, technical, environmental and economic aspects. An indicators database is further developed, including all the relevant data requirements, as well as existing and newly developed indicators assessing multi-sectoral systems' circularity. The MSWCA framework is conceptually applied to a fictional city, facilitating its understanding and practical use.

The environmental benefits of improving packaging waste collection in Europe

Collecting more waste via source separation waste collection systems is an essential part of increasing resource efficiency, achieving European recycling targets and closing the loop in a circular economy. Huge variation in the capture rates of packaging waste (paper, plastic, metal, composite material and glass) exists in Europe, even between municipalities with similar characteristics, which suggests there is great potential to increase the amount of these materials that can be recovered. In order to assess the environmental impacts linked to higher collection rates, a Life Cycle Assessment model was built that considers the reduced need for virgin materials as the system's loops are closed. An extra 18 million tonnes of waste could be collected annually in Europe if best practice collection strategies were to be deployed, leading to a 13% reduction in greenhouse gas production associated with the packaging and packaging waste. Although high collection performance is crucial for efficient resource use, improving source separation waste collection systems alone will not be enough to achieve recycling targets; material losses must be reduced throughout the value chain, i.e. at the sorting and recycling stages. By evaluating the circularity and environmental implications of current waste management, it can be shown at which points in the system the most improvement needs to be made for each material in order to facilitate the transition towards a circular economy.

Improved de-inking of inkjet-printed paper using environmentally friendly atmospheric pressure low temperature plasma for paper recycling

Nowadays, due to environmental pollution and natural energy consumption caused by waste paper, many researches are being conducted on the reuse of printed-paper. To recycle the paper, de-inking has to be performed. In this article, in order to reduce the use of the commonly used de-inking chemicals, the effect of an atmospheric pressure helium plasma treatment on the de-inking enhancement of printed-paper is studied. Through colorimeter and UV-visible spectrometer measurements the plasma treatment is shown to speed up the de-inking. While SEM observations and FTIR measurements suggest that the paper quality is retained upon plasma treatment, the increase of surface hydrophilicity measured by water contact angle measurements, compared to non-treated paper, is believed to enhance the fiber swelling of the paper and lead to a faster ink removal.

Protective role of luteolin against bisphenol A-induced renal toxicity through suppressing oxidative stress, inflammation, and upregulating Nrf2/ARE/ HO-1 pathway

For the development of renal diseases, oxidative stress (OS) is reasoned to be one of the risk factors. For the treatment or prevention of the renal disease, the use of antioxidants could be a hopeful therapeutic mediation as they retard or block the oxidative reaction along with the inflammatory process. Luteolin (Lut) is a plant flavonoid, a pharmacologically active component normally found in glycosylated forms in basic perilla leaf, green pepper, celery, seed, honeysuckle bloom, and chamomile blossom; it exhibits antioxidant activity. In this investigation, we explored the nephroprotective activity of Lut on bisphenol A (BPA)-induced nephron toxicity in rats. Orally administering Lut (100 and 200 mg/kg) diminished BPA-induced anomalies in the kidney, blood urea nitrogen, creatinine, and serum uric acid levels. Lut therapy reduced the BPA-influenced generation of inflammatory mediators, inclusive of tumor necrosis factor alpha, interleukin 6, and interleukin 1 beta. This was coupled with significant improvement in kidney histopathologic features. Lut enhanced the nuclear factor-like 2 (Nrf2) and heme oxygenase 1 (HO-1) expression, which showed protection against OS induced by BPA. The current outcomes of the study showed that Lut has a strong reactive oxygen species scavenging property and potentially decreases the lipid peroxidation as well as inhibits DNA damage in renal toxicity induced by BPA. In conclusion, the potential antioxidant effect of Lut may be because of its modulatory effect on the Nrf2/antioxidant response element (ARE)/HO-1 pathway, which means it protects the kidney from BPA-induced oxidative injury. © 2019 IUBMB Life, 2019.

Concentrations of POPs based wood preservatives in waste timber from demolished buildings and its recycled products in Japan

One of the major proportions of recycled persistent organic pollutants (POPs)-containing waste is timber originating from old buildings, utility poles, and cross-arms because POPs-based treatments were once a common means of preserving wood. In 2016 and 2017, we conducted the first survey in Japan on the residue concentrations of chlordanes (CHLs), pentachlorophenol (PCP), pentachloroanisole (PCA), and polychloronaphthalenes (PCNs) in waste timber (n = 55) and its recycled products (woodchip, n = 42; particle board, n = 3). In the recycled products, the highest concentrations detected were 0.86 mg kg^-1 CHLs, 3.0 mg kg^-1 PCP, 1.1 mg kg^-1 PCA, and 2.6 mg kg^-1 PCNs, which were one to two orders lower than the low POP content (LPC) limits for the environmentally sound management of wastes defined under the Basel Convention (50, 100, and 10 mg kg^-1, respectively). In the waste timber, which included bearers and columns from demolished buildings, the highest concentrations were 15 mg kg^-1 CHLs, 0.20 mg kg^-1 PCP, and 0.036 mg kg^-1 PCNs, no higher than about 30% of the LPC limit. The concentration of CHLs in timber bearer was significantly higher than those in timber column (p < 0.05). Although none of the waste timber or recycled products had concentrations exceeding the LPC limits, one means of ensuring low POP concentrations in recycled products is separating timber bearer from timber column when demolishing wooden buildings, according to the results in Japan. The timber column can be used to produce recycled products and the remaining timber can be used for heat utilization and power generation.

Flows, stocks, and emissions of DEHP products in Japan

The usage of products containing Bis (2‑ethylhexyl) Phthalate (DEHP) is widespread, mainly through the great variety of PVC products. However, DEHP has become a worldwide concern, due to the potential health and environmental risks it presents. In this study, material flow analysis and emission estimations for DEHP products in Japan, from 1948 to 2030, were performed. Moreover, an evaluation of the potentially damaging impacts on human health and the environment was completed through a lifecycle impact assessment approach. The analysis focused on three representative lifecycle phases - Production, Use and Treatment and Disposal. The peak flows of DEHP from Production to the Use phase were in 1996 with 285,300 tons for shipment and the stocks peaked in 2001 with 1,981,908 tons. Accordingly, in 2006 the peak of DEHP waste to the Treatment and disposal phase was 190,792 tons. The primary emissions were observed in the Use phase, due to the large stocks, with DEHP mostly being released to the pedosphere. The total emissions from the Use phase reached the maximum of 48,960 tons in 2000, whereas in the Production and Treatment and disposal phase it was 248 tons and 15 tons, respectively. Subsequently, concerning the evaluation of impacts, the damage to the human health was the most widespread impact, totaling 13,782 disability-adjusted life years (DALYs), compared with the damage to the ecosystems, with 0.12 species·year. Furthermore, the risk-risk tradeoffs between the lifecycle phases were clarified throughout the years.

A Review of Waste Management Decision Support Tools and Their Ability to Assess Circular Biowaste Management Systems

The circular economy concept offers a number of solutions to increasing amounts of biowaste and resource scarcity by valorising biowaste. However, it is necessary to consistently address the environmental benefits and impacts of circular biowaste management systems (CBWMS). Various decision support tools (DST) for environmental assessment of waste management systems (WMS) exist. This study provides a review of life cycle assessment based WMS-DSTs. Twenty-five WMS-DSTs were identified and analysed through a shortlisting procedure. Eight tools were shortlisted for the assessment of their applicability to deliver sustainability assessment of CBWMS. It was found that six tools model key properties that are necessary for assessing the environmental sustainability of CBWMSs, including waste-specific modelling of gaseous emissions, biogas generation or bioproduct composition. However, only two tools consider both waste-specific heavy metals content in bioproducts and the associated implications when applied on soil. Most of the shortlisted tools are flexible to simulate new technologies involved in CBWMS. Nevertheless, only two tools allow importing directly new background data, which is important when modelling substitution of new bioproducts developed in emerging biowaste refineries.

Contamination in plastic recycling: Influence of metals on the quality of reprocessed plastic

The global consumption of plastic continues to increase, and plastic recycling is highlighted as crucial for saving fossil resources and closing material loops. Plastic can be made from different polymers and contains a variety of substances, added intentionally to enhance the plastic's properties (metals added as fillers, colourants, etc.). Moreover, plastic can be contaminated during use and subsequent waste management. Consequently, if substances and contaminants are not removed during recycling, potentially problematic substances might be recycled with the targeted polymers, hence the need for quantitative data about the nature and presence of these substances in plastic. Samples of selected polymers (PET, PE, PP, PS) were collected from different origins; plastic household waste, flakes/pellets of reprocessed plastic from households and industry, and virgin plastic. Fifteen selected metals (Al, As, Cd, Co, Cr, Cu, Fe, Hg, Li, Mn, Ni, Pb, Sb, Ti, Zn) were quantified and the statistical analysis showed that both the polymer and origin influenced the metal concentration. Sb and Zn were potentially related to the production stage of PET and PS, respectively. Household plastic samples (waste and reprocessed) were found to contain significantly higher Al, Pb, Ti and Zn concentrations when compared to virgin samples. Only the concentration of Mn was reduced during washing, suggesting that parts of it was present as physical contamination. While most of the metals were below legal limit values, elevated concentrations in reprocessed plastic from households, aligned with increasing recycling rates, may lead to higher metal concentrations in the future.

Is there an environmentally optimal separate collection rate?

Material recycling often leads to environmental benefits when compared to thermal treatments or landfilling and is therefore positioned in the waste hierarchy as the third priority after waste prevention and reuse. To assess the environmental impacts of recycling and the related substitution of primary material, linear steady-state models of physical flows are typically used. In reality, the environmental burdens of collection and recycling are likely to be a non-linear function of the collection rate. This short communication aims at raising awareness of the non-linear effects in separate collection systems and presents the first non-linear quantitative model for PET bottle recycling. The influence of collection rates on the material quality and the transport network is analyzed based on the data collected from industrial partners. The results highlight that in the present Swiss recycling system a very high collection rate close to 100% yields optimum environmental benefits with respect to global warming. The empirical data, however, provided indications for a decrease in the marginal environmental benefit of recycling. This can be seen as an indication that tipping points may exist for other recycling systems, in which the environmental benefits from substituting primary materials are less pronounced than they are for PET.

Dynamic Stocks and Flows Analysis of Bisphenol A (BPA) in China: 2000-2014

Bisphenol A (BPA), a synthetic organic chemical, is creating a new category of ecological and human health challenges due to unintended leakage. Effectively managing the use and leakage of BPA can benefit from an understanding of the anthropogenic BPA cycles (i.e., the size of BPA flows and stocks). In this work, we provide a dynamic analysis of the anthropogenic BPA cycles in China for 2000-2014. We find that China's BPA consumption has increased 10-fold since 2000, to ∼3 million tonnes/year. With the increasing consumption, China's in-use BPA stock has increased 500-fold to 14.0 million tonnes (i.e., 10.2 kg BPA/capita). It is unclear whether a saturation point has been reached, but in 2004-2014, China's in-use BPA stock has been increasing by 0.8 kg BPA/capita annually. Electronic products are the biggest contributor, responsible for roughly one-third of China's in-use BPA stock. Optical media (DVD/VCD/CDs) is the largest contributor to China's current End-of-Life (EoL) BPA flow, totaling 0.9 million tonnes/year. However, the EoL BPA flow due to e-waste will increase quickly, and will soon become the largest EoL BPA flow. The changing quantities and sources of EoL BPA flows may require a shift in the macroscopic BPA management strategies.

Recycling of plastic waste: Screening for brominated flame retardants (BFRs)

Flame retardants are chemicals vital for reducing risks of fire and preventing human casualties and property losses. Due to the abundance, low cost and high performance of bromine, brominated flame retardants (BFRs) have had a significant share of the market for years. Physical stability on the other hand, has resulted in dispersion and accumulation of selected BFRs in the environment and receiving biota. A wide range of plastic products may contain BFRs. This affects the quality of waste plastics as secondary resource: material recycling may potentially reintroduce the BFRs into new plastic product cycles and lead to increased exposure levels, e.g. through use of plastic packaging materials. To provide quantitative and qualitative data on presence of BFRs in plastics, we analysed bromophenols (tetrabromobisphenol A (TBBPA), dibromophenols (2,4- and 2,6-DBP) and 2,4,6-tribromophenol (2,4,6-TBP)), hexabromocyclododecane stereoisomers (α-, β-, and γ-HBCD), as well as selected polybrominated diphenyl ethers (PBDEs) in samples of household waste plastics, virgin and recycled plastics. A considerable number of samples contained BFRs, with highest concentrations associated with acrylonitrile butadiene styrene (ABS, up to 26,000,000ngTBBPA/g) and polystyrene (PS, up to 330,000ng∑HBCD/g). Abundancy in low concentrations of some BFRs in plastic samples suggested either unintended addition in plastic products or degradation of higher molecular weight BFRs. The presence of currently restricted flame retardants (PBDEs and HBCD) identified in the plastic samples illustrates that circular material flows may be contaminated for extended periods. The screening clearly showed a need for improved documentation and monitoring of the presence of BFRs in plastic waste routed to recycling.

Methods to estimate the transfer of contaminants into recycling products - A case study from Austria

Recycling of waste materials is desirable to reduce the consumption of limited primary resources, but also includes the risk of recycling unwanted, hazardous substances. In Austria, the legal framework demands secondary products must not present a higher risk than comparable products derived from primary resources. However, the act provides no definition on how to assess this risk potential. This paper describes the development of different quantitative and qualitative methods to estimate the transfer of contaminants in recycling processes. The quantitative methods comprise the comparison of concentrations of harmful substances in recycling products to corresponding primary products and to existing limit values. The developed evaluation matrix, which considers further aspects, allows for the assessment of the qualitative risk potential. The results show that, depending on the assessed waste fraction, particular contaminants can be critical. Their concentrations were higher than in comparable primary materials and did not comply with existing limit values. On the other hand, the results show that a long-term, well-established quality control system can assure compliance with the limit values. The results of the qualitative assessment obtained with the evaluation matrix support the results of the quantitative assessment. Therefore, the evaluation matrix can be suitable to quickly screen waste streams used for recycling to estimate their potential environmental and health risks. To prevent the transfer of contaminants into product cycles, improved data of relevant substances in secondary resources are necessary. In addition, regulations for material recycling are required to assure adequate quality control measures, including limit values.

Inter-Sectoral Bisphenol A (BPA) Flows in the 2012 Chinese Economy

Bisphenol A (BPA), a widely used petrochemical compound, has become an emerging global environmental management challenge because its leakage is associated with potential environmental and human health impacts. Until now, available BPA statistics have been limited to the products that directly use BPA. In this study, we delineate direct and indirect BPA flows for the 2012 Chinese economy. We find that construction, production of educational and recreational products, and automobile manufacturing are the most BPA-intensive sectors in terms of total BPA flows (300, 157, and 130 Gg total BPA flows, respectively). The public management and health sectors, however, incur significant indirect BPA flows, defined as embedded and inter-sectoral BPA placed into use, even though direct BPA use by these sectors is limited. By revealing the currently overlooked indirect BPA flows, this study reveals data gaps that are highly relevant to improving the accuracy of estimated BPA flows and losses. The method used herein is transferrable to other emerging and environmentally relevant materials, thereby providing the holistic understanding needed for cities, regions, or nations to design effective policy interventions.

The mass flow and proposed management of bisphenol A in selected Norwegian waste streams

Current initiatives for waste-handling in a circular economy favor prevention and recycling over incineration or landfilling. However, the impact of such a transition on environmental emissions of contaminants like bisphenol A (BPA) during waste-handling is not fully understood. To address this, a material flow analysis (MFA) was constructed for selected waste categories in Norway, for which the amount recycled is expected to increase in the future; glass, vehicle, electronic, plastic and combustible waste. Combined, 92tons/y of BPA are disposed of via these waste categories in Norway, with 98.5% associated with plastic and electronic waste. During the model year 2011, the MFA showed that BPA in these waste categories was destroyed through incineration (60%), exported for recycling into new products (35%), stored in landfills (4%) or released into the environment (1%). Landfilling led to the greatest environmental emissions (up to 13% of landfilled BPA), and incinerating the smallest (0.001% of incinerated BPA). From modelling different waste management scenarios, the most effective way to reduce BPA emissions are to incinerate BPA-containing waste and avoid landfilling it. A comparison of environmental and human BPA concentrations with CoZMoMAN exposure model estimations suggested that waste emissions are an insignificant regional source. Nevertheless, from monitoring studies, landfill emissions can be a substantial local source of BPA. Regarding the transition to a circular economy, it is clear that disposing of less BPA-containing waste and less landfilling would lead to lower environmental emissions, but several uncertainties remain regarding emissions of BPA during recycling, particularly for paper and plastics. Future research should focus on the fate of BPA, as well as BPA alternatives, in emerging reuse and recycling processes, as part of the transition to a circular economy.