Proposal Requirement 3 Example: Bioreporter to Detect Polycyclic Aromatic Hydrocarbons

Writer: Swasti Singhai

Instagram: @swasti.singhai


Summary of Significance 

This study aims to develop a bioreporter, or engineered microbe, to produce a signal when in contact with polycyclic aromatic hydrocarbons through the use of bioluminescence. Because traditional methods are both expensive and labor-intensive, the development of a bioluminescent reporter strain can aid with the detection of PAHs in a faster, more cost-efficient, and easily scalable way [1]. 

Polycyclic aromatic hydrocarbons (PAHs) are environmental contaminants, falling under the category of polycyclic aromatic compounds. PAHs are primarily generated when organic compounds (ex. coal, oil, wood, garbage, gas, and tobacco) undergo combustion [4]. High-temperature cooking and commercially produced chemicals in the United States both generate PAHs. 

Animal studies show that certain PAHs also can affect the hematopoietic and immune systems and can produce reproductive, neurologic, and developmental effects [2,3]. Naphthalene, a type of PAH, can cause blood and liver abnormalities in addition to skin inflammation. Inhalation and ingestion of PAH can also cause the breakdown of red blood cells. The most significant effect of PAH toxicity is carcinogenicity, as some PAHs are known animal carcinogens and probable human carcinogens [3]. 

Mixtures of these compounds are exposed to humans through ingestion, inhalation, exposure to places that burn organic materials, and potentially through the skin (from soil) as well [4]. After PAH enters the body, it’s converted to metabolites, which can then be measured in the human body to quantify exposure. Though little recent research has been done, research measuring PAH metabolites in urine dating from the early 21st century indicates widespread exposure in the United States [4]. 

Though bioremediation, a technique used to transform contaminants to inert substances, is a safe and cost-effective option for removal of PAHs, the detection of PAHs must be accessible first. Due to the limited research on the detection of PAHs, no cost-efficient, and reliable techniques exist. However, bioluminescent bioreporters have been used for many environmental applications, including detecting chemicals after an oil spill, making them a viable option for the detection of PAHs as well. 


The author opens up introducing the aim of this study. As the rest of the section is talking about the significance of the study, the end goal must be clear from the very beginning. Then, the section transitions into a discussion about polycyclic aromatic hydrocarbons, which is also essential background knowledge to present. Then, the adverse effects are explained following the scale of people affected. An estimate of the magnitude and scale are both necessary to include so the audience understands the full scope of the research. This is extremely important when writing a proposal to apply for a grant, as the donors will want to know how beneficial your study will be. Following the toxicity and scale, the author discusses a technique that has been used in other applications and ends by implying that the technique will work in the detection of PAHs as well. The author could have added more statistics on the bioaccumulation and concentrations of PAH present in the natural environment. However, this is largely dependent on the data available (recency & reliability). Additionally, the author could have added supporting diagrams/charts to aid the data presented. Moreover, the author cited all references when any claims were made in the passage. Overall, this passage summarizes the significance and opens up the proposal efficiently and clearly, making it easier to go further in-depth on the specifics in later sections as well. 


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[4] - Polycyclic Aromatic Hydrocarbons (PAHs) Fact Sheet

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