There is a problem with the amount of harsh chemicals that are used to clean bathrooms. These harsh chemicals, such as bleach, can have many adverse effects when mixed with the wrong thing. Additionally, these chemicals can cause irritation to the skin and lungs of people which can be harmful. Essential oils could be a new direction for cleaning products that minimize these adverse effects and significantly limit the danger of the cleaning products we use daily. Perhaps a study that investigates the effectiveness of essential oils that are made from plants predominantly found in the PNW on killing bacteria that is grown from the school bathroom could solve this problem of if essential oils could be a good new direction towards cleaning products used in bathrooms. Using 12 large petri dishes and 20 small petri dishes, bacteria would be grown from different locations in the bathroom. Both the large and small dishes would grow 4 plates of bacteria from the toilet, sink, and floor, and the small petri dishes would additionally have bacteria from the soap and a control for each location. Essential oils would be made from the Western red cedar, Western sword fern, the Oregon grape, and the Boreal beard lichen with each oil being tested on each bacterial location. The validity of this study is best supported by the evidence that shows that essential oils often exhibit exceptional antimicrobial properties against bacteria and therefore these oils could potentially be the most effective against bacteria grown from the bathroom and be used as a new cleaning method. 

• Phyla - A family of bacteria where different subcategories of bacteria can fall into 

• Gram-Positive - A classification of bacteria represented by bacteria with no outer membrane nor complex cell walls

• Gram-Negative - A classification of bacteria represented by bacteria with an outer membrane and more complex cell walls

• Antimicrobial - A property of substances that can inhibit growth of pathogenic bacteria

• Essential oils - Concentrated extracts from various plants 

In my data, it was shown that in most situations, the essential oils made from PNW native plant life were ineffective in killing bacteria that grew in the bathroom. However, it was shown that the oils were capable of slowing growth in certain sets of bacteria. It was found in the small petri dishes that the Boreal beard lichen was only effective in slowing the growth in bacteria found from the soap dispenser, the Red cedar was only effective in slowing growth of bacteria in the sink, and the Oregon grape was only effective in slowing the growth of bacteria from the sink, similarly to the Red cedar. However, the Western sword fern was capable of slowing the growth of bacteria that grew in both the toilet and the floor (see Figure 1). In the large petri dishes, it was found that certain oils were also effective in slowing the growth of the bacteria. However, while certain oils slowed down the growth of these bacteria, there were three situations where all bacteria growth was stopped and there was no visible difference between before the oils were placed and after. It was found that the lichen essential oil stopped the growth of bacteria from the toilet and slowed the growth of bacteria from the sink. The Western red cedar was completely ineffective in slowing growth of bacteria, or killing it. All bacterial growth continued after the red cedar essential oil was placed. The Western sword fern was also able to stop growth of bacteria that came from the toilet and additionally it slowed down growth of bacteria from the floor. The Oregon grape was able to stop growth of bacteria from the toilet, however was completely ineffective on bacteria from the sink and floor (see Figure 2).

From my research, it can be concluded that in most situations, the essential oils made from PNW native plants were mostly ineffective. However, certain oils were effective in certain places, like previously mentioned. From this, I can conclude that my hypothesis that the essential oils would be completely effective against the bacteria was refuted because in most cases the oils had no effect on the bacteria. However it can also be concluded that the Western sword fern was the most effective essential oil in killing bacteria that grew in the bathroom. Additionally, it was the most consistent in the data as it worked in both the toilet and floor bacteria, in both the small and large petri dishes. However, not even the Western sword fern was completely effective in killing the bacteria as it only worked on the toilet and floor. More research would need to be done for the findings of these oils to be significant. Due to the lack of trial numbers, the data was not significant enough to say that the oils work always, and more testing needs to be done before these oils can be truly applied as a cleaning method that works. However, the location that the oils affected the most was the toilet bacteria, where in the large petri dishes it almost always worked, but also worked in the sword fern for the small petri dishes. Therefore, the Western sword fern, lichen, and Oregon grape could potentially serve as a cleaning method for the toilet, but not until after more data is collected to ensure it works every time. 

To conduct this research experiment further, the most important thing to do would be to test these oils on specific bacteria that is found in each part of the bathroom. This would mean to culture one specific bacteria type that is found in one specific location, and to test each oil on that specific bacteria to see how it works on that one specifically. This would provide more precise data on how well it works on each type of bacteria that grows in each place and further show which oils are working in which places, as well as what specific bacteria. Another way to further this research would be to test out a greater amount of PNW native plants. As previously stated, the PNW is home to a very diverse plant life, many of which exhibit medicinal properties. Testing different plants would give the potential for a plethora of possibilities into types of essential oils that could be used for their antimicrobial properties. It would also test to see if there are plants that work even better than the ones used in this study, and potentially work better than oils that are used today. To further this research I would also conduct a significant amount more trials to get as precise data as possible that can draw a detailed conclusion. 

• Nazzaro, F., Fratianni, F., De Martino, L., Coppola, R., & De Feo, V. (2013). Effect of essential oils on pathogenic bacteria. Pharmaceuticals, 6(12), 1451–1474. https://doi.org/10.3390/ph6121451 

• Flores, G. E., Bates, S. T., Knights, D., Lauber, C. L., Stombaugh, J., Knight, R., & Fierer, N. (2011). Microbial biogeography of public restroom surfaces. PLoS ONE, 6(11). https://doi.org/10.1371/journal.pone.0028132 

• Bioeducation - Bio-Rad Laboratories. (n.d.). Retrieved May 1, 2023, from https://www.bio-rad.com/webroot/web/pdf/lse/literature/Bulletin_5891A.pdf 

• How to make essential oils. Nourished Essentials. (n.d.). Retrieved May 1, 2023, from https://nourishedessentials.com/blogs/healthwellness/how-to-make-essential-oils

• U.S. National Library of Medicine. (n.d.). Essential oils of peppermint, orange or lemongrass kill most strains of fungal and bacterial infections. Positive health news. Retrieved May 1, 2023, from https://pubmed.ncbi.nlm.nih.gov/11366554/#:~:text=Essential%20oils%20of%20peppermint%2C%20orange,of%20fungal%20and%20bacterial%20infections 

• U.S. Department of Health and Human Services. (n.d.). Essential oils. National Institute of Environmental Health Sciences. Retrieved May 1, 2023, from https://www.niehs.nih.gov/health/topics/agents/essential-oils/index.cfm