Team:UrbanTundra Edmonton/Description
Description
Why Mars?
When asked of the prospect of human colonization on Mars, Stephen Hawking stated that, “It will completely change the future of the human race and maybe determine whether we have any future at all.” (Hawking, Stephen). While most would state that the billions of dollars put into space exploration should be best used to end world hunger and poverty - a never ending problem that we must resolve as members of a society - it is also important to think in a long-term mindset. We must consider what can happen to the human population hundreds to thousands of years from now. The only home that we as humans have ever known is Earth. However, as our population increases at an exponential rate (Haub, Carl), and surviving as a species on a tiny blue planet in the vacuum of space is no longer a guarantee, it is vital to beging thinking of alternatives; the possibilities of colonization within the cosmos.
A classic example would be the extinction of the dinosaurs. Roaming the Earth 65 million years prior to us, they remain as nothing but fossilized remnants. There are no longer traces of said dinosaurs walking the planet; what if this occurs to the human species? This is similar to the risk of monoculturing crops, where producing only one species is dangerous; what if a pathogen wipes out the entire population (Greentumble)? If the human species is only limited to Earth, what will happen if our Earth was not here? What if one colossal asteroid, or perhaps a natural disaster, wiped out the entire human existence? Whatever it may be, one thing is for sure: placing humans on more than one planet will allow for our existence to exist for thousands, if not millions, of years from now.
How Did We Get Here?
With the rapid rate of technological advancements over the past few decades, the idea of space colonization has been brought closer and closer, increasingly becoming a more tangible goal. Mars, our interstellar neighbor, is a planet with the same heat-range as that of Earth. It has become the prime target for human expansion in the cosmos. However, before we can even think to achieve this vision, there are a number of considerations that must be accounted for. Of such considerations includes a problem that is essential to solve, and is essential in order to allowing life to thrive on the Red Planet - the issue of perchlorate contamination on Martian soil.
In 2008, NASA’s Phoenix lander identified traces of perchlorate salts in Martian soil, ranging from concentrations of 0.5% to 1% (Davila et al). What does this mean? Well, perchlorate is a highly toxic substance that, at high concentrations, imposes negative health effects.
Perchlorate Health Effects and Locations
The main exposure pathway of perchlorate for humans is through the ingestion of contaminated drinking water sources. After having ingested of high doses of perchlorate, perchlorate ions inhibit the thyroid gland’s uptake of iodine, thereby disrupting functions of the thyroid gland (Srinivasan and Viraraghavan 1426). Consequently, this leads to a decreased production of thyroid hormones, recognized as hypothyroidism. As the thyroid plays an important role in metabolism and growth, both neurologically and physically, disruption of its function can lead to adverse health effects in humans in all stages of growth. For fetuses and infants, thyroid hormones are essential for the development of the central nervous system (Patel et al. 1). In children and adults, thyroid hormones regulate metabolism, heart rate, blood pressure, and body temperature.
Ultimately, perchlorate is a chemical that must be addressed before considering the colonization of Mars. Researchers at the University of Edinburgh confirmed that certain conditions of Mars, especially in the presence of perchlorate which can enhance the bactericidal effects of UV lights, make it nearly impossible for microorganisms to survive on its surface of Mars (Wadsworth and Cockell 1). Our proposed method is to use engineered E.Coli. in a regulated bioreactor system to reduce perchlorate in martian soil. We believe that developing a system to remediate the toxic martian soil brings us closer towards developing an environment on Mars that is comparable to Earth, ensuring that Mars can eventually sustain life.
Research into biological methods to remove and remediate perchlorate contaminants on Earth may prove equally as useful. On Earth, perchlorate is a chemical substance that is found both naturally and in manufactured products. Generally, perchlorate contamination is a result of utilizing products containing perchlorate. Acting as a strong oxidizer, perchlorate is commonly used in solid propellants for rockets, missiles, fireworks, and other pyrotechnics (Backus et al. 334). Perchlorate deposits on soil surfaces are initially a result of utilizing pyrotechnics, such as fireworks during festivals. This particulate matter containing perchlorate consequently is dispersed into remote areas by wind (Ye et al. 2495). Furthermore, sufficient precipitation may transport the perchlorate contaminants away from the area through surface runoff (Kumarathilaka et al. 671). Although disruption of the thyroid gland’s functions require large doses of perchlorate, it remains a chemical that is found in various locations on Earth and can lead to adverse effects, all of which must be carefully considered.
Works Cited
Backus, S.M., et al. “Determination of perchlorate in selected surface waters in the Great Lakes Basin by HPLC/MS/MS”, Chemosphere, vol. 61, Nov. 2005, pp 834-843 doi.org/10.1016/j.chemosphere.2005.04.054
Davila, Alfonso & Willson, David & D Coates, John & P Mckay, Christopher. "Perchlorate on Mars: A chemical hazard and a resource for humans." International Journal of Astrobiology. 2013. doi: 10.1017/S1473550413000189.
Greentumble. "Advantages And Disadvantages Of Monoculture Farming | Greentumble." Greentumble.com. (2016):1-3
Haub, Carl. "How Many People Have Ever Lived on Earth?" Population Reference Bureau. (2011): 1-3. Web.
Hawking, Stephen. "Why We Should Go Into Space." NASA's 50th Anniversary Lecture Series. NASA Office of Public Affairs, Washington. 21 Apr. 2008. Lecture.
Kumarathilaka, Prasanna, et al. “Perchlorate as an emerging contaminant in soil, water, and food.” Chemosphere, vol. 150, May 2016, pp. 667-677. doi.org/10.1016/j.chemosphere.2016.01.109
Patel, Jatin, et al. “Thyroid hormones and fetal neurological development” Journal of Endocrinology, vol 209, January 6, pp1-8. doi: 10.1530/JOE-10-0444
Srinivasan, Asha, and Thiruvenkatachari Viraraghavan. “Perchlorate: Health Effects and Technologies for Its Removal from Water Resources.” International Journal of Environmental Research and Public Health 6.4 (2009): 1418–1442. PMC. Web. 14 April 2009
Wadsworth, Jennifer, and Charles S. Cockell. “Perchlorates on Mars Enhance the Bacteriocidal Effects of UV Light.” Nature News, Nature Publishing Group, July 2017 doi:10.1038/s41598-017-04910-3
Ye, Long, et al. “Seasonal variations and factors influencing perchlorate in water, snow, soil, and corns in Northeastern China.” Chemosphere, vol. 90, Mar. 2013, pp 2493-2498
