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This paper examines infrastructure spending in a model economy. Infrastructure is subdivided into two types: one that makes future production more efficient, and another that decreases the risk of devastation to the future economy. We call the first type base infrastructure, and the second type risk-reducing infrastructure. Our model assumes that a single representative individual makes all the decisions within a society and optimizes their own total utility over the present and future. We then calibrate an aggregate economic, two-period model to identify the optimal allocation of today’s output into consumption, base infrastructure, and risk-reducing infrastructure. This model finds that many governments can make substantive improvements to the happiness of their citizens by investing significantly more into risk-reducing infrastructure.
The Philippines relies on a vast biodiversity of fishes as a staple food, but like many countries around the globe, experiences severe “leakages” of contaminants and pollutants in the environment. In order to better understand the relationship between environmental pollutants and public health, this research project measured the concentration of pollutants in a commonly consumed local fish (Siganus fuscescens), and then evaluated the potential health risks of eating this fish based on estimated average consumer weight and consumption levels. Fish sampled from four different sites located in Negros Oriental, Philippines were analyzed for organic contaminants using gas chromatography and mass spectroscopy. Pollutants quantified included polycyclic aromatic hydrocarbons (PAHs), pesticides, phthalates, and polychlorinated biphenyl (PCBs). Across the four study sites, fishes from Manjuyod showed the highest frequency of detection of different pollutants. However, phthalates and PAHs were found in similar concentrations in all four sites, with fishes from Dumaguete showing the highest level of PCBs compared to the other sampled sites. The U.S. Environmental Protection Agency’s guide for fish contaminants pinpoints several health risks associated with the chronic ingestion of these contaminants. Based on estimated average body weights of Filipino adult men, adult women, and children, and various consumption levels, people who eat the fish at or above the national average consumption level may be at increased risk for chronic health outcomes, such as cancer and/or other adverse effects. Specifically, due to the high concentration of PCBs in Dumaguete, selected populations who eat local fish from this site may be at higher risk than the citizens who eat the fish from other sites at similar consumption rates. These results can help to inform local and national policies on water quality, waste disposal, and fish consumption advisory programs.
The research objective was to determine the short-term ecological toxicity of ozonation byproducts on seed germination of three distinct plant types (radish, lettuce, and grass) compared to untreated and uncontaminated soils. We hypothesize that the reduction of heavy hydrocarbon contamination in soil by ozone application will provide more suitable habitat for the germinating seeds. The effect of ozone treatment on seed germination and seedling quality was measured using ASTM standards for early seedling growth in conjunction with a gradient of potting soil amendments. Ozonation parameters were measured using established methods and include total petroleum hydrocarbons (TPH), dissolved organic carbon (DOC), and pH.
This study demonstrated the TPH levels fall up to 22% with ozonation, suggesting TPH removal is related to the amount of ozone delivered as opposed to the type of crude oil present. The DOC values increase comparably across crude oil types as the ozonation dose increases (from a background level of 0.25 g to 6.2 g/kg dry soil at the highest ozone level), suggesting that DOC production is directly related to the amount of ozone, not crude oil type. While ozonation reduced the mass of heavy hydrocarbons in the soil, it increased the amount of ozonation byproducts in the soil. For the three types of seeds used in the study, these changes in concentrations of TPH and DOC affected the species differently; however, no seed type showed improved germination after ozone treatment. Thus, ozone treatment by itself had a negative impact on germination potential.
Future research should focus on the effects of post-ozonation, long-term bioremediation on eco-toxicity. By helping define the eco-toxicity of ozonation techniques, this research can improve upon previously established ozone techniques for petroleum remediation and provide economic and environmental benefits when used for soil treatment.