Alternative Air Purification Using Traditional Methods

Airborne bacteria can’t be seen with the naked eye, but they can still pose a risk to our health so it’s important to have effective ways to control and reduce them. Many bacteria are harmless but many others can cause serious illness and disease, especially in the very young, very old, and those who are immunocompromised. Pneumonia, tuberculosis and Legionnaires' disease are some examples of potentially fatal diseases that are spread through contact with these airborne germs.The purpose of this experiment was to determine if a natural alternative exists that can effectively sanitize air without relying on harsh chemical agents. People with respiratory conditions such as asthma or allergies could benefit, as well as children, the elderly, and anyone sensitive to strong chemical cleaners. It could also help households, schools, workplaces, and healthcare settings that want safer, more natural ways to improve indoor air quality. It may also be more environmentally friendly, helping reduce chemical pollution and promoting more sustainable, natural solutions for cleaner air. By combining traditional knowledge and modern science this experiment could benefit society by cleaning the air.

It was hypothesized that sage smoke could remove bacteria in the air.

To start, the optimal exposure time for agar-containing petri dishes to collect airborne bacteria was determined by placing dishes in a sealed room for 1–6 hours; a 2-hour exposure period was found to yield sufficient bacterial growth. After this, petri dishes were placed in four different indoor environments—a living room, bedroom, laundry room, and medical office—before and after burning sage, to assess changes in airborne bacterial content. Each room was sealed to minimize external contamination, and dishes were incubated for 36 hours at 30–37 °C. Then, the colonies on the petri dishes showing airborne bacteria content before and after the burning of sage were counted and noted. This process was repeated in the 4 different rooms with 4 trials each. Each trial was separated by a three-day interval, during which normal human activity was allowed to restore background bacterial levels and any sage smoke effects were permitted to fully subside.

In the end, the results consistently demonstrated a decrease in bacterial colony growth following the burning of sage. The second trial in each room had a markedly lower amount of bacteria present compared to the first trial after three days of regular use of the room. This was noted again between the second and third trial. In fact, the numbers were so low in the third trial it was deemed necessary to perform a fourth trial to confirm the results. The results from all rooms showed a direct correlation between the burning of sage and bacteria content in the air. The variations in each room's initial (before sage burning) bacterial count went from a high of 30+ to a low of 5. Regardless of the initial count, the bacterial content of the air decreased in every trial but one and that trial appears to be an outlier.

It was the analysis of the data showing the even lower initial counts of bacteria in Trials 3 and 4 that led to the determination that the antibacterial properties of the sage smoke appeared to have a lasting effect.

Slide 2 shows the percentage decrease in bacterial colonies after burning sage (this is similar to how commercial products demonstrate their effectiveness).

Slide 3 shows a sample of petri dishes used during the experiment to collect results.

It was concluded that not only could sage remove bacteria from the air, but that the antibacterial qualities of sage smoke lasted in a room long after the smoke cleared. This proved the hypothesis was correct. It was found that a natural alternative to synthetic chemicals can eliminate airborne bacteria with equal effectiveness. This experiment proves that there is a compound in sage that has antibacterial properties and that it could be used to remove airborne bacteria. From a Two-Eyed Seeing perspective, these findings are understood by bringing together Indigenous ways of knowing and scientific methods, offering a more complete view of sage’s potential as a treatment for air.

In the future, more trials can always be conducted and for this experiment specifically,

burning sage for a longer or shorter amount of time may cause variation on the results. It would

be valuable to test different periods of time. It would also be beneficial to determine what chemical compound in particular has the antibacterial effect in the sage. Gram staining could also be done to determine the types of bacteria that were in the air. The completed experiment could serve as a foundational piece for future and more detailed ongoing research relating to sage's antibacterial properties.

I would like to express my gratitude for all the people who helped me succeed with this project. First, my family for helping me properly seal rooms and prevent any contamination during trials. I would also like to thank all community members who shared stories of traditional knowledge with me which is what inspired this project. Finally, my teachers and my Dad gave me great feedback and advice to help me improve this project. I owe it to all of you!

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