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Microplastic pollution is occurring in most ecosystem, yet their presence in high altitude clouds and their influence on cloud formation and climate change are poorly known. Here we analyzed microplastics in cloud water sampled at the summits of Japan mountains at 1300–3776 m altitude by attenuated total reflection imaging and micro-Fourier transform infrared spectroscopy. We observed nine microplastics including polyethylene, polypropylene, polyethylene terephthalate, polymethyl methacrylate, polyamide 6, polycarbonate, ethylene–propylene copolymer or polyethylene–polypropylene alloy, polyurethane, and epoxy resin. Microplastic were fragmented, with mean concentrations ranging from 6.7 to 13.9 pieces per liter, and with Feret diameters ranging from 7.1 to 94.6 μm. Microplastics bearing hydrophilic groups such as carbonyl and/or hydroxyl groups were abundant, suggesting that they might have acted as condensation nuclei of cloud ice and water. Overall, our finding suggest that high-altitude microplastics cloud influence cloud formation and, in turn, might modify the climate. [ABSTRACT FROM AUTHOR]

Snowfall is regarded as a carrier of airborne microplastics (MPs). Deposited snow can function as a temporary reservoir for atmospheric MPs. Nevertheless, knowledge and understanding of MPs in snow remain sparse. This study investigates the abundance, composition, size (> 30 µm), and shape of MPs in snow specimens from various nature preservation areas and also from urban sites in Hokkaido. Various polymeric-type MPs with mostly fragmentary shapes were detected among the specimens. More than half of MPs were in the smallest size class (30–60 µm), implying the presence of more MPs below the limit (< 30 µm). Concentrations of MPs ranged from 1.5 × 102 to 4.2 × 103 particles/L. The results demonstrated that microplastic abundance generally decreases concomitantly with increasing remoteness of sampling sites. Observed features of MPs at different locations and their relation to geographical settings have indicated that the ubiquitously observed fine particles (mainly alkyd, ethylene–vinyl acetate, and polyethylene) are attributable to long-distance atmospheric transportation, whereas the rubber and larger particles especially found near highways and cities are from local sources of plastic. Taken together, these findings suggest important implications for elucidating the nature and distribution of atmospheric MPs. [ABSTRACT FROM AUTHOR]

Fungi play an important role in the degradation of biodegradable plastics (BPs) in soil. However, little is known about their dynamics in the soil during the degradation of BPs. We studied the community dynamics of BP-degrading fungi during poly(butylene succinate-co-adipate) (PBSA) film degradation in two different types of soils using culture-dependent and culture-independent methods. The Fluvisol and the Andosol soils degrade embedded PBSA films at high and low speeds, respectively. The number of PBSA emulsion-degrading fungi that increased in the Fluvisol soil was higher than that in the Andosol soil after embedding with PBSA films. We succeeded in detecting internal transcribed spacer 1 (ITS1) regions those matched that of the fungi by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) in both soils. Our results suggest that fungal community analyses using PCR-DGGE in combination with BP degraders isolation techniques enables the monitoring of BP films-degrading fungi. Monitoring fungal population dynamics during the degradation of films comprising poly(butylene succinate-co-adipate) in a Fluvisol and an Andosol soil. [ABSTRACT FROM AUTHOR]

In the plastic product lifecycle, consumers are the main stakeholders who purchase, consume, and dispose of plastic products. To be able to take optimal measures to induce changes in consumer behavior to achieve sustainable plastic management, daily-use plastic products should be classified by consumers' necessity. However, consumers' evaluations of the necessity of individual plastic products remain to be examined. Here, we selected 50 plastic products from the Japanese households that are used and disposed of by consumers on a daily basis, and then conducted a large-scale questionnaire survey of 10,000 residents of Japan in which we asked respondents to evaluate the subjective necessity and substitutability of each of the targeted 50 products. To discuss future measures tailored to individual products or groups of similar products, we conducted hierarchical clustering analysis based on the respondents' evaluation of each of the products. The classified seven clusters could be divided into two groups, which were characterized by a low and high necessity for consumers. In the four clusters characterized by a low necessity, most of the products were single-use plastic products and the rate of the options indicating a lack of necessity was more than 44% for each product. In contrast, the other three clusters included plastic containers and packaging, durable products, and products made from synthetic fibers, but few single-use plastic products, and showed a higher response rate of more than 55% for the options indicating necessity. Then we also investigated domestic consumption of each product and obtained the Japanese total consumption of the 50 targeted products as 3.619–4.007 million t per year. As a result of our estimation, if the consumers can stop their use of the unnecessary products or have access to suitable substitutes, millions of tons of products could be eliminated as a maximum reduction potential. Overall, our survey highlighted the importance of classification of plastic products based on the consumers' necessity and proposed possible targets of policy intervention on future sustainable management in terms of individual plastic products. • Questionnaire revealed the consumers' evaluation of daily-use plastic products in Japan. • Classification of the products was conducted by consumers' necessity and substitutability. • Japanese potential for reducing consumption of the products was estimated. • Product-based approach can be a clue to implement future measures for plastics. [ABSTRACT FROM AUTHOR]

Consumer acceptance of bioplastics is a sine qua non for transitioning to a bioeconomy. This necessitates the elucidation of consumer preferences and perceptions of bioplastics and effective education on bioplastics to facilitate informed choices. However, these factors have not been studied sufficiently. Therefore, we conducted a discrete choice experiment and text mining among 12,000 Japanese consumers for three products using a treatment-control design, where the respondents in the treatment group learned the basic distinctions between bio-based and biodegradable plastics. Our study revealed the complexity of their preferences; bioplastics were not unconditionally preferred, and perceptions and values played a critical role in this stance. Knowledge tests and co-occurrence network analyses confirmed the limited comprehension of bioplastics among respondents. Their preferences had certain differences and similarities with those reported in previous European studies. For example, contrary to European consumers, most respondents in this study did not favor the use of biomass. They preferred sugar cane over other feedstocks, indicating that environmental concerns were undervalued. Both Japanese and European consumers preferred domestic bioplastics but for different reasons. Our study provides Japanese industries and governments a reference for currently acceptable and promising types of bioplastics (e.g., those with increased CO 2 emission reduction) for development. Simultaneously, these institutions can convince Japanese consumers to prefer other types (e.g., those with more inclusion of biomass) by correcting their limited understanding of bioplastics. Our study added the diversity of consumers to those found in the previous studies, which may be informative for other countries to develop effective policies with their consumers' potential uniqueness in mind. Furthermore, our study proved that learning the basics of bioplastics can influence preferences for certain attributes (e.g., biodegradability) of the sampled bioplastic products. [Display omitted] • Not all aspects of bioplastics are preferred (e.g., greater inclusion of biomass). • Respondents had a limited understanding of bioplastics. • Learning the basics of bioplastics changed their preferences for some attributes. • Japanese and European consumers prefer domestic bioplastics for different reasons. • A policy effective in one place may not necessarily be so in another. [ABSTRACT FROM AUTHOR]

Fragmentation of degraded plastics and release of smaller secondary microplastics is usually attributed to the growth of environmental stress cracks. Analysis of crack patterns derived from chemical degradation can be useful not only for assessing the cause of plastic fracture and evaluating the useful lifetime of a product, but it can also potentially provide valuable information on the generation of microplastics. However, the literature with respect to microplastics generation is generally limited to surface observations of polypropylene and polyethylene. Here, we used ion-beam milling to prepare cross-sections of fragments of 15 plastic products made from five commodity plastics (polypropylene, polyethylene, polystyrene, polyvinyl chloride, and polyethylene terephthalate) that were collected at two beaches in Japan, and then we examined the microstructures of those cross-sections by means of scanning electron microscopy and energy dispersive X-ray spectroscopy. Crack growth in the depth direction was examined to provide insights into microplastic generation behavior. In all of the polypropylene samples, and some of the low-density polyethylene and polystyrene samples, cracks with a depth exceeding 100 μm from the sample surface were observed. Considering that crack growth causes fracture of degraded plastic and microplastic release, these observations suggest the release of sharp-edged microplastics from the crack fracture surface. In contrast, in the high-density polyethylene and polyvinyl chloride samples, crack growth was limited to within 20 μm of the sample surface, suggesting the release of irregularly shaped microplastics and additive particles. The present results suggest that the degradation behavior of plastic products in the depth direction is dependent on the type of plastic. • Cross-sectional microstructural analysis of marine macroplastics was conducted. • Crack growth of five commodity plastics in the depth direction was evaluated. • Polypropylene samples showed crack growth to a depth of more than 100 μm. • High-density polyethylene and polyvinyl chloride showed additive release. • Crack growth patterns are highly dependent on the type of plastic. [ABSTRACT FROM AUTHOR]

The article focuses on interest of Japanese business enterprises in the field of biotechnology. Photographic film and digital imaging equipment producer Fujifilm Inc. plans to make biotech one of the main focuses of research at the new center, scheduled to begin operation in March 2006. Toyota launched a pilot facility for the production of biodegradable plastics made with polylactic acids derived from natural sources in 2004. Imaging equipment maker Olympus has invested in a business incubation company to add to its traditional strengths in areas like endoscopy, imaging and diagnostics.