The Environmental Impacts of Alternative Food Waste Treatment Technologies in the U.S.

A Life Cycle Assessment (LCA) was conducted to determine the environmental impacts of several waste treatment scenarios for a suburban New York (U.S.) municipality. The study goal was to determine if separate food waste recovery and management was environmentally sounder than waste-to-energy incineration (the baseline case). Three alternatives, enclosed tunnel composting, enclosed windrow composting, and anaerobic digestion with subsequent enclosed windrow composting of residuals, were examined considering the entire residual waste stream (not just separated food wastes). Impact categories assessed were climate change, environmental eutrophication and acidification, resource depletion, and stratospheric ozone depletion. A normalized, aggregated impact assessment was created to compare the treatments across categories. The anaerobic digestion scenario scored best, followed by the tunnel composting and the baseline waste to energy incineration scenarios, and, last, the enclosed windrow composting scenario. Although it was possible to select an alternative that decreased environmental burdens compared to the business-as-usual case, all modeled scenarios resulted in higher overall environmental burdens than savings, underscoring the need to avoid creating waste to conserve resources and reduce environmental burdens, and ultimately lead to more sustainable waste management practices

Drivers of Food Wastage and their Implications for Sustainable Policy Development

There has been growing interest in establishing food waste prevention and recovery programs throughout the world. The drive to target food waste stems from increasing concerns about resource conservation, food security, food waste’s environmental and economic costs, and a general trend in the waste management industry to transition to more sustainable practices. Here the drivers of residential, institutional, and commercial food waste generation in developed countries, particularly in the U.S., are explored. The impacts of food system modernization on food waste generation are examined, particularly impacts related to food system industrialization, urbanization, globalization, and economic growth. Socio-demographic, cultural, political, and economic drivers of food wastage are described with emphasis on how food waste perspectives may vary globally. Specific behaviors and attitudes which result from many of these waste drivers are then discussed. The examination of the range of food wastage drivers are used to provide insight into the best policy approaches to sustainably manage food waste. Food waste prevention policies are placed in context of the waste generating behaviors and attitudes that they address. A review of important background information on food waste is also provided, including definitions of key terms, food waste history, quantities of food waste generated, and the importance of food waste prevention for sustainability, as this information is all critical for effective policy development

Degradable Plastics and their Potential to Affect Solid Waste Systems

Plastic waste forms a substantial part of municipal solid waste and has caused environmental concerns, particularly due to chemical contamination of the environment and effects from persistent litter. Plastics also complicate waste management processes, such as by having poor recovery rates through recycling, and causing contamination in composting operations. One potential means to address some of these challenges is through degradable plastics which, unlike conventional plastics, are designed to decompose at an accelerated rate in specific environments. Degradable plastics aim to address the end-of-life of plastic products and are intended to reduce the environmental impacts associated with their use and management. The first generation of degradable plastics did not meet marketing claims; some of the more recent formulations, partly as a consequence of third party certifications, are more compliant. However, many plastics that are labelled as degradable do not decompose very readily, and it is not clear that litter will be diminished to any great degree through their use. In addition, user confusion regarding degradable definitions is common. Multiple formulations mean not all degradable plastics address compost contamination, and most degradable plastics do not address other problems associated with plastics waste management. Therefore it is not clear that degradable plastics constitute a major technological advance. In fact, they may be more harmful than helpful to waste management systems at this time. Here we discuss how these materials perform in different aspects of solid waste programs: recycling, composting, WTE incineration, and landfills, as well as the potential for these plastics to reduce litter problems, both on land and at sea

Degradable Plastics and Solid Waste Management Systems

Plastics, which are woven into the fabric of modern life, have consequential impacts on the environment. Many of these are associated with end-of-lifetime processes, and include chemical contamination of the environment and effects from litter. Plastics also complicate waste management processes, causing contamination in composting operations, and having poor recovery rates through recycling. Plastics that are not as biologically recalcitrant, that decompose when use is done, have been perceived as solutions to at least some of these problems. The first generation of degradable plastics did not meet marketing claims; some of the more recent formulations, partly as a consequence of third party certifications, are more compliant. However, many plastics that are labeled as “degradable” do not decompose very readily, and it is not clear that litter will be diminished to any great degree through their use. In addition, because not all plastics are or will be degradable, user confusion is and will be common. Multiple formulations mean not all degradable plastics address compost contamination, and most degradable plastics do not address other problems associated with plastics waste management. Therefore it is not clear that degradable plastics constitute a major technological advance; in fact, overall they may be more harmful than helpful

A Management Framework for Municipal Solid Waste Systems and its Application to Food Waste prevention

Waste management is a complex task involving numerous waste fractions, a range of technological treatment options, and many outputs that are circulated back to society. A systematic, interdisciplinary systems management framework was developed to facilitate the planning, implementation, and maintenance of sustainable waste systems. It aims not to replace existing decision-making approaches, but rather to enable their integration to allow for inclusion of overall sustainability concerns and address the complexity of solid waste management. The framework defines key considerations for system design, steps for performance monitoring, and approaches for facilitating continual system improvements. It was developed by critically examining the literature to determine what aspects of a management framework would be most effective at improving systems management for complex waste systems. The framework was applied to food waste management as a theoretical case study to exemplify how it can serve as a systems model for complex waste systems, as well as address obstacles typically faced in the field. Its benefits include the integration of existing waste assessment models; the inclusion of environmental, economic, and social priorities; efficient performance monitoring; and a structure to continuously define, review, and improve systems. This framework may have broader implications for addressing sustainability in other disciplines

Quantification of Food Waste Disposal in the United States: A Meta-Analysis

Food waste has major consequences for social, nutritional, economic, and environmental issues, and yet the amount of food waste disposed in the U.S. has not been accurately quantified. We introduce the transparent and repeatable methods of meta-analysis and systematic reviewing to determine how much food is discarded in the U.S., and to determine if specific factors drive increased disposal. The aggregate proportion of food waste in U.S. municipal solid waste from 1995 to 2013 was found to be 0.147 (95% CI 0.137-0.157) of total waste, which is lower than that estimated by USEPA for the same period (0.176). The proportion of food waste increased significantly with time, with the western U.S. region having consistently and significantly higher proportions of food waste than other regions. There were no significant differences in food waste between rural and urban samples, or between commercial/institutional and residential samples. The aggregate disposal rate for food waste was 0.615 pounds (0.279 kg) (95% CI 0.565-0.664) of food waste disposed per person per day, which equates to over 35.5 million tons (32.2 million tonnes) of food waste disposed annually in the U.S

Differences in Waste Generation, Waste Composition, and Source Separation across Three Waste Districts in a New York Suburb

Six tonnes of discards and recyclables from three waste districts in a New York suburb were sorted in 2012. The districts were chosen because one had a higher recycling percentage, one had median performance, and one was a low performing district. ASTM standards were followed for the waste composition sorting. The results showed, as expected, that the waste district with the highest recycling rate appeared to have the highest separation efficiencies, leading to greater amounts of recyclable materials being source separated. The waste districts also had different overall waste generation, both in terms of the amounts of wastes generated, and their composition. The better recycling district generated less waste, but had a higher percentage of recyclables in the waste stream. Therefore, in some sense, its waste stream was enriched in recyclables. Thus, although the residents of that district recovered materials at a higher rate, they also left large amounts of recyclables in their discards – as did the residents of the other districts. In fact, the districts only recycled between one quarter and less than half of all available recyclables, so that their discards were comprised of up to one third recyclable materials. This level of performance does not appear to be unique to this Town; therefore, we believe that additional recovery efforts through post-collection sorting for recyclables may be warranted

Fucoidan Inhibits Smooth Muscle Cell Proliferation and Reduces Mitogen-activated Protein Kinase Activity

AbstractObjectives and design: fucoidan has previously been shown to inhibit the proliferation of arterial smooth muscle cells both in animal models and in vitro. However, the mechanisms behind the anti-proliferative effects of this polysulfated polysaccharide are not known in detail. Here, the inhibitory effect of fucoidan on rat aortic smooth muscle cell proliferation was examined and compared with the effects of heparin after stimulation with fetal calf serum, platelet-derived growth factor BB, basic fibroblast growth factor, heparin-binding epidermal growth factor, and angiotensin II. Materials and methods: the cultures were analysed with respect to cell proliferation and DNA synthesis by cell counting and measurement of3H-thymidine incorporation. Phosphorylation of mitogen-activated protein kinase and nuclear translocation of phosphorylated mitogen-activated protein kinase were studied by immunoblotting and immunocytochemistry. Results: fucoidan was shown to be a more potent inhibitor of smooth muscle cell proliferation than heparin. Fucoidan also reduced growth factor-induced activation of mitogen-activated protein kinase and prevented nuclear translocation of phosphorylated mitogen-activated protein kinase. Conclusion: fucoidan is a more potent anti-proliferative polysulphated polysaccharide than heparin and may mediate its effects through inhibition of the mitogen-activated protein kinase pathway in a similar manner as heparin