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There is an urgent need to implement sustainable plastic use and disposal to prevent further negative consequences. As they involve human behavior, intervention measures for inducing individual human behavioral changes toward this implementation are essential. While studies and good practices are rapidly increasing in this regard, it is not sufficient for policymakers. There is no guarantee that good practice in one place will be equally good in another context. Therefore, policymakers require appropriate guidance to choose suitable intervention measures for their context. This study proposes a behavioral barrier-based framework (BBBF) to aid policymakers in selecting context-appropriate intervention measures. The BBBF is built on the assumption that certain barriers can prevent people from making desirable behavioral changes. The BBBF helps policymakers choose suitable intervention measures for lowering the barriers that inhibit desirable sustainable plastic use and disposal-related behaviors. The framework includes a generic list of barriers derived from possible intervention measures that integrate market-based, regulatory, and behavioral approaches to expedite the identification of critical barriers and corresponding intervention measures. Local stakeholders are involved in the whole process to reflect contextuality and to elicit context-specific intervention measures, desirable behavioral measures, and their barriers. The BBBF was developed and tested through its application in Kyoto City, Japan. This BBBF application included 1000 citizens, two focus groups, 14 businesses, and three city officials connected to the issue, and identified fifteen intervention measures and three barrier types to induce 16 desirable behavioral changes for achieving Kyoto City's four established policy targets. Also see: https://micro2022.sciencesconf.org/427731/document, In MICRO 2022, Online Atlas Edition: Plastic Pollution from MACRO to nano

In Japan, fisheries’ product has decreased since the 1980s, and the government amended the fisheries law in 2020 to shift to managed fisheries. However, awareness of seafood sustainability is still low. This study identifies the reason for the low awareness and states the necessary actions to increase sustainable seafood consumption. The proactive stakeholders in seafood supply were surveyed to determine the current status of sustainable seafood sales. Marine Stewardship Council-certified fishers and MSC’s Chain-of-Custody certification holders answered the questionnaires. Fishers showed a positive attitude, citing proactive sales channel expansions and contributions to sustainability. Distributors were primarily passive, mainly because they obtained the certification at the request of their clients, and about half of them did not disseminate information between consumers and suppliers. Both fishers and distributors expect the government to promote campaigns and education. The stages of the awareness of producers, intermediary trade, and retailers are different and did not align. Therefore, if the supply chain stakeholders proactively educate themselves, choose sustainable products from the fishers, and pass the sustainability information to the consumers, sustainable seafood consumption would progress.

Single use plastics pose environmental and socioeconomic problems in our life and ecosystems. After a 14 year attempt, Kenya successfully adopted a plastic bag ban for secondary packaging in August 2017. Globally, the impact of plastic bag policies are limited or not documented. Using a questionnaire survey, this study explored consumer consciousness towards the ban, reusable bag usage behavior, and estimated plastic bag consumption before the ban. Results indicate that the ban has favorable support of about 67% from consumers. The perceptions towards cleanliness and waste management were different between urban and rural respondents. This highlighted differences in awareness creation and enforcement of the ban. Behaviorally, ownership of reusable bags tripled to 12 bags per household. Plastic reusable bags were the most owned and most discarded bags within 6 months. Moreover, a report estimates that 300 million bags (8.3–6.7 bags person−1 y−1) were consumed annually in 2005 and 2017 before the ban, the current study estimates the ban potential eliminates about 6.2 billion bags (138 bags capita−1 y−1) from the waste stream. It is thus important to incorporate usage frequency, reusable bags standards, waste and health factors in policy formulation. Proper usage of reusable bags prevents waste and lowers their environmental burden.

Pacific island countries are facing critical challenges in managing the growing amount of increasingly diverse wastes because of changing lifestyles and the concentration of populations in urban areas. Although marine plastic waste is an issue in the Pacific region, there have been almost no studies of the estimation and impacts of ocean plastic waste, and measures to control such waste, in these countries. Here, first we conducted a questionnaire survey about consumption and disposal of plastic products at households in Samoa as one of the examples of Pacific island countries to grasp the flow of plastic materials and awareness or behaviour for plastic waste. Then we quantified ocean plastic waste and discussed the effective and needed countermeasures in Pacific island countries. The total amount of mismanaged plastic waste was estimated to be 327,000 or 156,000 t y−1 (depending on the scenario) in Pacific island countries. The regional Pacific island countries contribution to the global total mismanaged plastic waste was estimated to range from 1.3% to 2.7%. The amount of mismanaged plastic waste per capita in some Pacific island countries, such as Solomon Islands and Micronesia, was also ranked highly globally. The main reasons seem to be that waste collection rates are relatively low in rural areas and rates of plastic waste generation are high. To implement solutions, including improving municipal solid waste collection, reducing plastic waste, improving the collection and recycling of plastics, and the integration of a number of policies is essential.

Energy recovery from small and medium scale waste thermal treatment facilities in the municipalities of Japan is challenging, owing to low power generation efficiency and high economic demands. Gas Engine (GE) generation is considered an efficient resource utilization method in these facilities. In this study, new and consistent feedstock, Refuse Paper and Plastic Fuel (RPF), and wood pellets were tested in an air-blown Fluidized Bed Gasifier (FBG) for syngas utilization in a GE. With temperatures ranging from 700 to 940 °C and varying Equivalence Ratios (ER) of 0.3–0.5, some of the most important product gas characteristics were analyzed, including the Lower Heating Value (LHV) and tar concentration levels. Gas composition results revealed that the concentration tendencies varied for the product gases CO, H2, and hydrocarbons, depending on the feedstock type, whereas the same tendencies were observed for CH4 and tar concentrations. Through the ER range, the LHV of product gas for RPF and wood pellets was 3.4–5.9 MJ/Nm3. Tar concentrations decreased to 2.5–14.0 g/Nm3-dry as the ER was raised. The optimal ER for LHV performance in GE generation was approximately 0.4 for RPF and wood pellets, and remaining tar concentrations were about 5.0 g/Nm3-dry at the gasifier exit.

This study provides information on the disaster waste management practices and disposal methods employed in Kathmandu Valley for debris generated by the Gorkha Earthquake on April 25, 2015. We also quantify the amount of building debris generated and managed at destinations within the core city area of Kathmandu Valley, which was diverted from the government-proposed disposal site. This research involved field visits, interaction with communities, meetings with officers related to debris management, and reference to published reports. Disaster waste management in Nepal included the reuse/recycling of building materials in new construction or as filling materials in land development. Debris were also disposed on low-lying areas, down the cliff, and river bank; however, the disposal method was open dumping. Of the estimated 3.23 million tons of potential debris generated in the core city area of Kathmandu Valley, 1.07 million tons were managed 2 years after the Gorkha Earthquake, of which 0.63 million tons were disposed on river banks, along the ring road, and in open spaces, and the remaining 0.44 million tons were salvaged for reuse or sold for recycling or disposed in other isolated areas. Approximately 2.17 million tons of building debris is yet to be managed.

Millions of tons of debris can be generated by natural disasters, impacting the surrounding environment and posing health risks to the public. Proper handling and treatment of such waste is essential to overcome potential hazards as well as to reduce the burden on natural resources during the reconstruction phase. Disaster waste management can have social, economic, and environmental benefits if planned effectively. This mini-review focuses on the destruction caused and debris generated by the 2016 Kumamoto Earthquake in Japan. In addition, it elaborates upon the treatment of debris in Kumamoto at temporary and secondary storage sites by segregation and the adoption of a full-scale recycling system. It also shows that cooperative networks involving numerous organizations are important in managing a large amount of disaster waste. Finally, it presents comparative discussions of different aspects of disaster waste management in the Kumamoto Earthquake event and other disasters. The experience gained from the Kumamoto Earthquake is important for future disaster waste management planning.

The landfill sites in Vietnam are struggling to carry huge amounts of organic waste every day. While the domestic demand of using organic fertilizers for clean agriculture is increasing, these organic materials are disposed in a wasteful way. This study indicated that the nitrogen (N) concentration of the waste that include septic tank sludge (STS), food waste (FW) and sludge from seafood waste water treatment plant (SFS) is quite high by 965 mg/L, 34,314 mg/L and 1,756 mg/L. In this study, an Anaerobic Digester_Continuously Stirred Tank Reaction (AD CSTR ) system was established to recover the N from these wastes. The AD CSTR was made of 5 mm thick tempered glass, with the dimension of the tank is H x D x R = 1,000 mm x 300 mm x 300 mm. The C/N ratio used for the AD CSTR was 25, which was identified by pre-testing seven small AD systems with different C/N ratios. The result revealed that after 50 d of anaerobic digestion, the Carbon (C) and Nitrogen (N) concentrations of liquid product was 9,628.3 mg/L and 648.5 mg/L, and the carbon to nitrogen ratio (C/N) was 11.35 as well, equivalent to 78.2 % of recovering efficiency. This study also indicated the potential to recover nutrition, produce organic fertilizer from recycling the STS, FW and SFS in Vietnam, significantly contribute to reducing waste to the disposals.

Significant quantities of building waste were generated from collapsed residential and dilapidated buildings as a result of the disastrous Gorkha earthquake in Nepal on April 25, 2015. In this study, in relation to the field damage investigation of the earthquake hit area and based on the building types, different types of building waste produced from each building are estimated and evaluated. An estimation procedure was established to assess the amount of debris resulting from earthquake. In Kathmandu Valley, different types of buildings generated different quantities of building waste per unit area, and the values for these building types ranged from 1.90 to 3.23 ton m− 2 in weight and 0.89 to 1.57 m3 m− 2 in volume respectively. Residential buildings in Nepal generated a larger amount of waste per unit area (ton m− 2) than buildings in Japan and China. Waste amounts (excluding that in the foundation) generated by public reinforced concrete buildings in Nepal were similar to the amounts generated by reinforced concrete buildings in Japan and China. Wooden buildings had the highest volume per unit area of building waste in Japan, as compared to those in Nepal and Sri Lanka. These results can be used to estimate the amount of building debris that must be cleared for emergency response after a disaster. This information is vital to pre-disaster planning to establish disaster management protocols for smooth recovery operations.

In this study, the amount of prevented household waste in Kyoto city was quantified using three methods. Subsequently, the greenhouse gas (GHG) emission reduction by waste prevention was calculated in order to monitor the impact of waste prevention. The methods of quantification were "relative change from baseline year (a)," "absolute change from potential waste generation (b)," and "absolute amount of activities (c)." Method (a) was popular for measuring waste prevention, but method (b) was the original approach to determine the absolute amount of waste prevention by estimating the potential waste generation. Method (c) also provided the absolute value utilizing the information of activities. Methods (b) and (c) enable the evaluation of the waste prevention activities with a similar baseline for recycling. Methods (b) and (c) gave significantly higher GHG reductions than method (a) because of the difference in baseline between them. Therefore, setting a baseline is very important for evaluating waste prevention. In practice, when focusing on the monitoring of a specific policy or campaign, method (a) is an appropriate option. On the other hand, when comparing the total impact of waste prevention to that of recycling, methods (b) and (c) should be applied.

For 35 years, Kyoto City has conducted detailed household waste composition surveys under the guidance of Kyoto University by dividing household waste into approximately 400 categories. In addition, the city has conducted detailed composition surveys of commercial waste generated by businesses. These surveys show that food loss accounts for approximately 40% of total waste, of which leftovers and untouched food account for about 40% in both households and business facilities. Consequently, the annual generation of household and commercial food loss is estimated at about 30,000 tons. Various efforts have been made to reduce waste, including food loss, but further reduction in environmental burden is needed. Thus, Kyoto City revised the ordinance for waste reduction, and in March 2015, formulated a new municipal waste management plan. The plan not only includes the 2Rs (reduce, reuse), but also, for the first time in Japan, sets quantitative targets for reducing food loss. Kyoto City must ensure that the necessary waste reduction measures are clearly explained to the residents and business operators. To ensure that this plan is successful, it is important to clarify concrete actions that residents and business operators should implement, along with their effects.

Batteries sometimes contain precious or toxic substances (e.g. nickel, cobalt, lead, mercury, cadmium). However, the collection and recycling rate of small batteries were low in Japan. We focus on cobalt in lithium ion (Li-ion) batteries and conduct chemical analysis, questioner survey and flow analysis in Japan. Results of chemical analysis showed that the concentration of cobalt in Li-ion batteries was around 20% regardless of the year manufactured or the manufacturer. As a result of the consumer questionnaire survey, it became clear that 70% or more of the small batteries are not being removed when small electronic products are finally disposed. The survey also revealed that recognition of the law and system for collection and recycling of small rechargeable batteries is approximately 30–40%. Substance flow analysis showed that both production and demand for Li-ion batteries (cobalt) have increased during 2002–2010. The collection rate for used Li-ion batteries was about 10% during this period; uncollected batteries were either stored or disposed through incineration and landfill as municipal solid waste.

Shortly after the March 11th earthquake and tsunami in eastern Japan, a Task Team for Disaster Waste Management and Reconstruction was established within the Japan Society of Material Cycles and Waste Management (JSMCWM). One of the major tasks undertaken by the team was to create a manual entitled, Strategies for Separation and Treatment of Disaster Waste. In this paper, this JSMCWM manual is introduced, followed by a review of existing guidelines for disaster waste management in various countries. We identify useful guidelines created by international agencies, national and local governments. The JSMCWM manual adds our new experiences, especially characterized by a huge scale of disaster and tsunami information, to the existing knowledge with an emphasis on separation and subsequent treatment options. It should be desirable to share our knowledge and experiences, not only domestically but also with other countries in the world, especially regions that could be affected by large earthquake and tsunami events.

Reduce, reuse, and recycle (3R) policies form the basis of waste management and global warming countermeasures globally, so we conducted a comparative study of 3R and waste management policies in the European Union (EU), USA, Korea, Japan, China, and Vietnam. An international workshop for 3R and waste management policymakers was held in Kyoto, Japan, and a bibliographic survey was also conducted to collect data. 3R policies are clearly given priority in the hierarchy of waste management in every country studied. Thermal recovery, which includes power generation from waste heat and methane gas collected from organic waste, is also a priority; this is consistent with the increased use of countermeasures to reduce greenhouse gas (GHG) emissions. In the EU, waste management is characterized by practical and effective 3R policies through the development of realistic regulations and by the policymakers’ desire to simplify management systems. The policy ideal in China, however, is the development of a circular economy that targets reductions in the amount and hazardousness of waste. Limits on the number of final disposal sites, strategies for procuring resources, and GHG emission countermeasures are closely linked with 3R policies, and further development of 3R policies in parallel with such issues is expected.

We give an overview of the management systems of household hazardous waste (HHW) in Japan and discuss the management systems and their risks. To get basic information, we conducted a survey of consumers to discover their behavior and awareness of HHW items throughout the entire life cycle, which is made up of the purchase, use, and disposal of a product. The results showed that many people hold end-of-life batteries, fluorescent lamps, empty spray cans, and others in their houses after use. Also, the results showed that a lot of such waste items were discarded in waste streams different from those stipulated by local governments. In particular, many people do not remove NiCd batteries inside products such as shavers or cordless phones before discarding. On the other hand, people’s knowledge of and concern regarding the risks, collection, and recycling of HHW were high. When information about the risks was specifically presented in the questionnaire, people tended to show a more positive intention to participate in a collection and recycling system compared to those who were not presented with such information. Our studies on NiCd batteries and fluorescent lamps showed that it is important to collect and recycle HHW to control the domestic and international flows of cadmium and mercury.

We summarized the mercury flow of mercury-containing products from their manufacture to their disposal in Japan and discussed the current management of mercury-containing hazardous household waste (HHW). The mercury flow originating from these products was estimated to be about 10-20 tonnes annually, about 5 tonnes of which was attributable to fluorescent lamps, the major mercury-containing product in Japan. The recent rapid increase in digital home electronics with liquid crystal displays (e.g.,televisions, personal computers, mobile phones, and digital cameras) has led to a marked increase in the production of backlights, which are also fluorescent and contain mercury. Most of the annual flow was disposed of as waste, with only 0.6 tonnes Hg recovered. The mercury flow for end-of-life fluorescent lamps (excluding backlights) was analyzed under three scenarios for Kyoto, Japan for 2003: the present condition scenario, the improved recycling scenario, and the complete recycling scenario. Under the present condition scenario, mercury flow was calculated to be 34 kg Hg for incineration, 21 kg Hg for landfill, and only 4 kg Hg for recycling. The complete recycling scenario shows a simple flow, with all mercury recycled. Under this scenario for Kyoto, we calculated that a cyclic system having 47 kg of mercury (3.5 tonnes Hg in Japan) could be established if all fluorescent lamps (excluding those stored in residences) were collected and recycled. Mercury is a HHW priority chemical, and we need to limit its use and establish a closed-loop system. There are currently no regulations to achieve this, and the management of most HHWs is left to local governments. Therefore, products are disposed of in landfills or incinerated, except for some that are voluntarily collected and recycled. In order to recycle all of the waste fluorescent lamps, we must have a complete recycling system that has a high rate of public participation in collection. We also must have a closed-loop system of mercury recovery and reuse in which all stakeholders participate. Furthermore, it is important to share information and policies regarding fluorescent lamp recycling and related technologies with other countries, especially those in other countries, where fluorescent lamps are becoming more popular because of their high energy efficiency and long life. Also, it is important to develop mercury free and energy efficient lamps including LEDs (light emitting diodes).

水銀を含む蛍光管を取り上げ, 日本における水銀の物質フロー解析により, 有害物質を含む家庭製品の循環システム構築の方向性を検討した。水銀の物質フロー解析より, 製品由来の水銀は年間10～20ton流通しており, うち5tonが蛍光管由来であること, 回収される水銀は0.6tonのみで大半が廃棄物として処理・処分されていること, 原料段階では100ton以上のレベルで流通しており, 年次的に変化が大きいことがわかった。また, 蛍光管の循環・廃棄フロー推定より, 現在は水銀フロー量として, 最終的には焼却と埋立への負荷が大きく, リサイクル量は小さいと考えられた。水銀を含む蛍光管を使用する限りは究極的には蛍光管の全量リサイクルが望ましいが, そのためには, 回収への高い参加率や閉鎖系での再生品利用までを考慮に入れた循環システムを実現する必要があり, 情報周知や回収システムの検討に加え, 何らかの規制策や新たな技術およびビジネスモデルの創出を検討すべきと考えられた。

Animal bedding made of waste wood samples from seven different plants in Japan were chemically analyzed in terms of persistent organic pollutants (POPs) including polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/DFs), coplanar polychlorinated biphenyls (Co-PCBs), drin compounds, chlordane compounds and various inorganic toxic compounds (Cr, Cu, As, B, Cd and Pb) to investigate the chemical characteristics and levels of contamination. Further investigation was conducted to determine the success of applying the Chemically Activated Luciferase Expression (CALUX) bioassay to the waste wood samples in combination with a cleanup procedure for the detection of dioxin-like compounds in order to develop the CALUX bioassay as a rapid and cost-effective screening/monitoring method and a contributive tool to risk management in the waste wood recycling process. For the cleanup procedure, crude extracts from wood samples were prepared by dimethylsulfoxide (DMSO)/n-hexane extraction, and then the extracts were processed by silica gel–44% sulfuric acid reflux treatment at 70 °C for 60 min to yield the bioassay fractions.The presence of POPs and inorganic toxic compounds were confirmed in most of the litter samples. In particular, Co-PCBs in one sample (litter dust) showed a high concentration level (1,200,000 pg/g, 240 pg TEQ/g), suggesting the potential for contamination from demolition waste.The CALUX assay-determined TEQs (CALUX-TEQs) were significantly high in the sample after DMSO/n-hexane extraction, probably due to labile aryl hydrocarbon receptor (AhR) ligands such as PAHs; however, they were remarkably reduced through a single silica gel–44% sulfuric acid reflux treatment. The ratio between CALUX-TEQ values and WHO toxicity equivalent values (WHO-TEQ) obtained by congener-specific chemical analysis ranged from 0.058 to 22 and show comparatively good agreement. Underestimation in some samples, however, was observed where WHO-TEQ values of Co-PCBs contributed greatly to total WHO-TEQ values. Reasons for this gap could be lower CALUX assay-determined relative potencies (REPs) than the WHO-TEFs for these congeners or AhR-antagonistic effects of non dioxin-like PCBs which coexist at higher concentration than Co-PCBs. The CALUX assay is proposed as a promising application in the recycling process of wooden materials. Keywords: Wood, CALUX, Persistent organic pollutants

今後大量に廃棄されると考えられる薬剤処理木材には, 各種化学物質が残存していると考えられる。廃木材リサイクリングルートにおけるそれらのヒト健康リスクを評価するため, 曝露ポイントとして, 廃木材の1) 切断作業, 2) 室内利用をあげ, 経気道・経口曝露ルートによるガス状・粒子状の重金属類 (Cr, Cu, As) , PCP (ペンタクロロフェノール) , PCDD/DFs (ダイオキシン類) 及びPAHs (多環芳香族炭化水素) の曝露解析を行った。その結果, 廃木材切断作業や室内利用に伴う経気道及び経口での化学物質曝露量が日常レベルを大きく上回るほか, 継続的な曝露がヒト健康へのリスクを発癌リスク10-4にまで高める可能性が示唆された。

Our previous study demonstrated that compounds in indoor dusts strongly inhibit thyroxine (T4) binding to the human thyroid hormone transport protein transthyretin (TTR) in vitro. Exposure assessment indicated that house dust is an important medium of exposure of children to TTR-binding compounds when binding potency and dust ingestion rates are high. Here, we used chemical fractionation with in vitro competitive human TTR-binding assay and GC-MS to analyze the TTR-binding compounds in a sulfuric-acid-treated dust extract. 2,4,6-Tribromophenol (TriBPh) and 2,3,4,5,6-pentachlorophenol (PeCPh) were potent TTR-binding compounds in all dust samples. 2,4,6-TriBPh- and 2,3,4,5,6-PeCPh-derived theoretical T4 equivalents (T4EQs), calculated arithmetically from the concentrations and relative potencies, accounted for about 40-70% of experimental T4EQs detected in indoor dusts, indicating that these compounds contributed strongly to the TTR-binding potency of indoor dust. Indoor sources of 2,4,6-TriBPh might be brominated flame retardants currently used in household materials such as electrical appliances. In contrast, the 2,3,4,5,6-PeCPh might be trace evidence of past use in agricultural chemicals and preservatives in indoor or outdoor environments, because its use has been banned since 1990 in Japan. 2,4,6-TriBPh and 2,3,4,5,6-PeCPh are ubiquitous potential thyroid-disrupting compounds in the home and work environments of Japan and other countries.

End-of-life vehicles (ELV) have become a global concern as automobiles have become popular worldwide. An international workshop was held to gather data and to discuss 3R policies and ELV recycling systems, their background and present situation, outcomes of related policies and programs, the framework of recycling and waste management, and case studies on related topics in several countries and regions, as well as the essential points of the comparison. Legislative ELV recycling systems are established in the EU, Japan, Korea, and China, while in the US, ELV recycling is managed under existing laws on environmental protection. Since automobile shredding residue (ASR) has a high calorific value and ash content, and includes heavy metals as well as a mass of unclassified fine particles, recycling ASR is considered highly difficult. Countries with a legislative ELV system commonly set a target for recovery rates, with many aiming for more than 95 % recovery. In order to reach this target, higher efficiency in ASR recovery is needed, in addition to material recycling of collectable components and metals. Environmentally friendly design was considered necessary at the planning and manufacturing stages, and the development of recycling systems and techniques in line with these changes are required for sound ELV management.