Researchers at ASU have identified opportunities to reduce risk to human health and the environment by changing the composition and disposal practices of polymers. Although plastics have benefited society in innumerable ways, the resulting omnipresence of plastics in society has led to concerns about the hazards of constant, low-level exposure and the search for options for sustainable disposal.

The team used examples from public health and medicine-sectors that have particularly benefited from polymer applications, to highlight the benefits of using plastics in certain applications and to pinpoint opportunities for reducing risks from all plastics’ uses. These include phasing out polymers that contain components associated with negative health effects, diminishing the need to dispose of large quantities of plastic through reduction and reuse, and promoting and developing less harmful alternatives to conventional plastics.

For additional discussion please see the publication Plastics and Environmental Health: the Road Ahead available online here.

Building energy assessment often focuses on the use of electricity and natural gas during the use phase of a structure while ignoring the energy investments necessary to construct the facility. This research develops a methodology for quantifying the “embedded” energy and greenhouse gases (GHG) in the building infrastructure of an entire metropolitan region. “Embedded” energy and GHGs refer to the energy necessary to manufacture materials and construct the infrastructure. Using these methods, a case study is developed for Los Angeles County.

Healthcare infection control has led to increased utilization of disposable medical devices, which has subsequently led to increased adverse environmental effects attributed to healthcare and its supply chain. In dental practice, the dental bur is a commonly used instrument that can either be reused or used once and then disposed. To evaluate the disparities in environmental impacts of disposable and reusable dental burs, a comparative life cycle assessment (LCA) was performed. The comparative LCA evaluated a reusable dental bur (specifically, a 2.00mm Internal Irrigation Pilot Drill) reused 30 instances versus 30 identical burs used as disposables.

The LCA methodology was performed using framework described by the International Organization for Standardization (ISO) 14040 series. Sensitivity analyses were performed with respect to ultrasonic and autoclave loading. Findings from this research showed that when the ultrasonic and autoclave are loaded optimally, reusable burs had 40% less of an environmental impact than burs used on a disposable basis. When the ultrasonic and autoclave were loaded to 66% capacity, there was an environmental breakeven point between disposable and reusable burs. Eutrophication, carcinogenic impacts, non-carcinogenic impacts, and acidification were limited when cleaning equipment (i.e., ultrasonic and autoclave) were optimally loaded. Additionally, the bur’s packaging materials contributed more negative environmental impacts than the production and use of the bur itself. Therefore, less materially-intensive packaging should be used. Specifically, the glass fiber reinforced plastic casing should be substituted for a material with a reduced environmental footprint.

This paper’s intent is to explore the environmental gap analysis tool, Life Cycle Assessment (LCA), as it pertains to the decision-making process.

As LCA is more frequently utilized as a measurement of environmental impact, it is prudent
to understand the historical and potential impact that LCA has had or can have on its inclusion in public policy domain - specifically as it intersects the anticipatory governance framework and the supporting decision-making precautionary principle framework. For that purpose, LCA will be examined in partnership with the Precautionary Principle in order to establish practical
application.

LCA and Precautionary Principle have been used together in multiple functions. In two
case studies, the California Green Chemistry Initiative and in Nanotechnology uncertainty, there is a notion that these practices can create value for one another when addressing complex issues.

The recommendations presented in this paper are ones that recognize the current
dynamics of the LCA field along with the different sectors of decision makers. For effective
catalytic initiatives, adoptions of these recommendations are best initially leveraged by
government entities to lead by example. The proposed recommendations are summarized into
the following categories and explored in further detail later in the paper:
       1. Improvement in data sharing capabilities for LCA purposes.
       2. Common consensus on standards and technical aspects of LCA structure.
       3. Increased investment of resource allocation for LCA use and development.

The current study conducts a comparative LCA of two alternative structural retrofit/ strengthening techniques - steel jacketing, and the carbon fiber reinforced polymer (CFRP) retrofit. A cradle-to-gate system boundary is used for both techniques. The results indicated that the CFRP retrofit technique has merits over the conventional steel jacketing in all three impact categories covered by this study. This is primarily attribute to the much less material consumption for CFRP retrofit as compared to steel jacketing for achieving the same load carrying capability of the retrofitted bridge structures. Even though the transoceanic transportation of carbon fiber has been taken into account in this study, the energy consumption and environmental impacts of CFRP transportation is still much smaller than steel due to it light weight property. The impacts of CFRP retrofit are mainly focused in the material manufacturing phase, which implies that the improvements in the carbon fiber manufacturing technology could potentially further reduce the environmental impacts of CFRP retrofit.

Hemcrete is an alternative, environmentally‐friendly building material gaining adherents in Great Britain and other European countries. It is an attractive choice as a building material because it is made from a renewable resource, hemp, a hardy plant that is a close, but non‐hallucinogenic relative of marijuana. This plant is relatively easy to cultivate, requires little in the way of pesticides or fertilizers, and almost all parts can be used for various products from paper to textiles to food.

Hemcrete is made from a mixture of lime, water, and the fibrous outer portion of the hemp plant called the “hurd” or “shive”. When mixed, it is worked and placed much like conventional concrete ‐ hence the name. However, that is where the similarities with concrete end. Hemcrete is not comparable to concrete on a strength basis, and is better described as an alternative insulation product. When built into walls of sufficient thickness, Hemcrete offers high thermal efficiency, and has strong claims to being carbon negative. The purpose of this study
was to evaluate this claim of carbon negativity, and to compare these environmentally friendly qualities against conventional fiberglass batt insulation.

Our model was constructed using two identically sized “walls” measuring eight feet square by one foot in depth, one insulated using Hemcrete, and the other using fiberglass. Our study focused on three areas: water usage, cost, and carbon dioxide emissions. We chose water
usage because we wanted to determine the feasibility of using Hemcrete in the Phoenix metropolitan region where water is a troubled resource. Secondly, we wished to evaluate the claim on carbon negativity, so CO2 equivalents throughout the production process were measured. Finally, we wished to know whether Hemcrete could compete on a cost basis with more conventional insulation methods, so we also built in a price comparison.

Since the cultivation of hemp is currently unlawful in the United States, this study can help determine whether these restrictions should be relaxed in order to allow the construction of buildings insulated with Hemcrete.

Many relationships exist between humans and their animal companions. Regardless of the relationship, the costs of pet ownership are more than just veterinary bills and the purchase of pet food. The purpose of this study is to examine the environmental impacts associated with ownership of canus lupus familiaris, more commonly known as the domesticated dog. Since dogs are carnivorous by nature, there has already been significant interest in the ecological ‘pawprint’ of pet food, or the pressure that dog food production exerts on the environment.

This study utilizes Life Cycle Assessment (LCA) to determine the environmental impacts of industrial pet food production and furthermore, pet ownership through nutritional requirements. Additionally, this study aims to examine how pet food type—beef or lamb—can influence greenhouse gas (GHG) emissions. The approach taken by this study is that of a hybrid input-output LCA, combining Economic Input Output (EIO-LCA) data and process-level data to examine how supply chain decisions made by pet food manufactures can affect the ecological ‘pawprint’ of the domestic dog. The EIO-LCA provides an economy-wide lens, whereas, process-based LCAs provide data relevant to specific materials and processes. This approach was used to compare the environmental impacts associated with environmentally friendly supply chain decisions compared to the typical environmental impact of dog food.

Urban landscaping palm tree waste in the form of palm frond trimmings and bark shavings that is currently handled as municipal solid waste by the City of Phoenix and other major municipalities can be handled in more cost effective ways and lead to reductions in emissions and greenhouse gases. While many cities have green organics collection and diversion programs, they always exclude palm tree waste due to its unique properties. As a result, an unknown tonnage of palm tree waste is annually landfilled as municipal solid waste. Additionally, as the tonnage is unknown, so are the associated emissions, greenhouse gases, and costs. An attributional lifecycle assessment was conducted in the City of Phoenix from the perspective responsibility of the City of Phoenix’s Public Works Department.

An increase in population and need to protect the planet has created many initiatives and research goals in developing alternatives methods of fueling. Federal and state policies have provided a push for industries to find ways to of reducing their impact on the environment while maintaining competitiveness. In the sector of alternative fuels, large policies such as the Renewable Fuel Standards (RFS) in the United States are making goals to reduce vehicular fuel from coal and oil, and focus on alternative fuels such as ethanol and biodiesel. Along with the RFS and other federal policies, states are introducing independent initiatives to promote the use of alternative fuels.

Research has shown that other crops besides corn can feasibly be used to produce ethanol for fuel use. One of the major crops of interest currently is switchgrass (Panicum Virgatum L.) because of its ability to grow under a variety of weather conditions and soil types. Switchgrass does not require as much maintenance as corn and is a perennial grass that can have high yielding fields for up to 9 years.

This report focuses on the impacts from using switchgrass-derived ethanol to meet the state of Arizona’s policy to have government fleet vehicles operating on alternative fuels. The study uses a life cycle assessment (LCA) approach to evaluate 22 million gallons of ethanol produced in Arizona and stored at fueling stations for use. Impacts in land use, global warming, and water quality are evaluated using software tools and databases in Ecoinvent and Simapro.

The results of the study indicate that the cultivation and harvest phase of the process will contribute the most to negative environmental impacts. According to the study, application of heavy nutrient fertilizer and the machinery needed for the additional agriculture have the potential to contribute over 36 million moles of hydrogen and 89 million CTU eq. to the air, soil, and water.