Center for Earth Systems Engineering and Management

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.

The leading source of weather-related deaths in the United States is heat, and future projections show that the frequency, duration, and intensity of heat events will increase in the Southwest. Presently, there is a dearth of knowledge about how infrastructure may perform during heat waves or could contribute to social vulnerability. To understand how buildings perform in heat and potentially stress people, indoor air temperature changes when air conditioning is inaccessible are modeled for building archetypes in Los Angeles, California, and Phoenix, Arizona, when air conditioning is inaccessible is estimated.

An energy simulation model is used to estimate how quickly indoor air temperature changes when building archetypes are exposed to extreme heat. Building age and geometry (which together determine the building envelope material composition) are found to be the strongest indicators of thermal envelope performance. Older neighborhoods in Los Angeles and Phoenix (often more centrally located in the metropolitan areas) are found to contain the buildings whose interiors warm the fastest, raising particular concern because these regions are also forecast to experience temperature increases. To combat infrastructure vulnerability and provide heat refuge for residents, incentives should be adopted to strategically retrofit buildings where both socially vulnerable populations reside and increasing temperatures are forecast.

Here I plan to use CLCA to evaluate the environmental impact (and economy by using MFA??) by changing traditional crop to AVP1 GM crop. In this study I will compare wild type (WT) and AVP1 transgenic romaine lettuce (Lactuca sativa cv. conquistador). This is a study of P fertilizer being applied on romaine lettuce from gate to grave and making a comparison between WT and AVP1 romaine lettuce. The system boundary would be commercial P fertilizers applied on all lettuce in the U.S. The lettuce includes head lettuce, leaf lettuce, and romaine lettuce. The amount of P fertilizers such as inorganic, organic, and imported, will be identified and quantified. The amount of nitrogen and potassium fertilizers will also be quantified along with P fertilizer. The amount of water will be compared between the two different lettuces as the AVP1 lettuce grows faster and the amount of days of watering would be fewer. Eutrophication will be assessed as well as N2O emission. As AVP1 lettuce has a bigger root system, I will try to quantify the extra amount of CO2 fixed into the soil via AVP1 lettuce. I will also try to project the impact of AVP1 lettuce on market price. The functional unit of LCA portion is kg usage of N and P2O5 per ton of lettuce and the functional unit of MFA is kg/ha.