Here is a link to my Capstone Presentation.

https://osu.zoom.us/rec/share/6-dVM5_913lOWJHo2HGPBqAnLIW-T6a81SkarqZexR1J6jsC7SxXtB4zYNpWYmKa?startTime=1598132539000

My Capstone Project is complete.

Overall, the results were roughly what I would have predicted. Interestingly, no bacteria were visible using my microscope, this could simply be because there was no bacteria on the slides or that my microscope failed to view them.  The physical filters performed the best overall on average while the chemical treatment did not remove particles from the water significantly. However, I was surprised to see that the cheaper physical filter (the Sawyer Mini ~$30) performed better than the MSR filter (~$90). The control had an average of 10 particulates per slide while the Coleman chemical treatment had an average of 9.4 particulates per slide. It is worth noting that the Coleman treatment is designed to kill bacteria, not remove particulates, so this was somewhat expected. As my microscope didn’t see any bacteria, I can’t attest to its sterilization ability. The physical filters performed much better, with the Sawyer and MSR units averaging 1.2 and 2.8 particulates respectively.

To improve the experiment for the future, I would change some things.

I would use a better quality microscope and laboratory-grade equipment to ensure more accurate results. I couldn’t make out any live bacteria in any of my samples. And it was difficult to differentiate between particulates and air bubbles trapped within the microscope slide.  I would also consider switching back to the P&G chemical treatment I planned to use but couldn’t due to a lack of supply. This treatment has a coagulant that would make it more comparable to the physical filter devices. Finally, I would look to run tests for chemicals/pesticides or other dissolved materials to see if any of the methods had any effect despite claiming not to.

While this wasn’t part of my original study, I allowed a jar of untreated pond water and a jar of water treated with the MSR filter to sit open next to each other for a month. This revealed an interesting result. The jar of untreated water had developed a slightly green tint, indicating there were some biological contaminants in the sample. The filtered jar displayed no such green tint, indicating that any living cells had been filtered out.

Here is a photo of the two jars originally, the right jar has been filtered.

Here are the jars after a month undisturbed, the left jar was filtered a month earlier.

I learned a lot about conducting research throughout this project. The experience I’ve gained will be extremely useful if I decide to pursue research opportunities in the future. It feels odd that this is the final step to earning my STEM scholars designation, it’s two years in the making and yet I feel as if I just started college yesterday. I’m very grateful for the opportunities that STEM Scholars have provided me with so far and look forward to what lies ahead.

To close, I’ll include some photos of my project.

The MSR Filter:

The Sawyer Mini Filter:

The Coleman Chemical Treatment:

A slide filtered with the Sawyer Mini:

Versus a slide of water treated with the Coleman Chemical Treatment:

My project is underway!

I selected a local pond rather than using many different water sources as I originally planned. I realized that managing all of these water samples would overcomplicate the data I was attempting to collect. It would also be too difficult to travel to different sources due to the pandemic.

I collected a water sample from a nearby pond that collects drainage from the streets. The pond is stocked with fish so it should have plenty of micro-organisms to observe. There is also the potential for chemical runoff that will not be removed by the filters.

Here are some photos of the pond and of my equipment.

I have had to make some revisions to my project’s methodology due to the COVID-19 pandemic. Some items are currently unavailable that I had planned to utilize for my investigation. The proctor & gamble water purification tablets are out of stock, this is unfortunate as they have a unique coagulant that can remove particulates from solution creating clear, sanitized water. This would have been extremely interesting to test against other physical filters. As a substitute, I will utilize Coleman brand water purification tablets that sanitize water but do not contain any method of removing particulates from the solution. This will likely appear when samples are viewed under a microscope and could skew results. Also, due to the pandemic, I had to purchase a low-cost commercially available microscope which may not be as effective at viewing samples as a laboratory-grade microscope. It will be interesting to see what effect these changes have on the results.

Equipment to be Utilized:

• Compound Microscope with camera setup & Slides
• P&G Water Purification Packets
• Sawyer Mini Water Filter System
• MSR Miniworks EX Microfilter System
• Beakers, Pipets, and other experiment materials
• 1 A gallon of distilled water.

A sample of water from a natural source will be obtained using a five-gallon bucket. This will serve as the base sample that all tests will be derived from. From this base sample, five microscope slides will be prepared. After stirring the base sample before each slide to equally distribute any contaminants, a pipet will draw a small amount of the sample to prepare a slide. Each slide will be observed under the microscope and contaminants will be counted. The average of these slides will be used to extrapolate the concentration of contamination of the base water sample.

After stirring the base container, a sample of water roughly one liter will be drawn from the base sample into a sterilized container. This will be repeated three additional times to obtain a total of four one-liter samples. Each sample will be labeled with the method of filtration it will undergo. Prior to filtration, the one-liter samples will be shaken to ensure that any contaminants are evenly distributed. The two physical filter systems (excluding the powder treatment which has a different procedure) will be flushed with distilled water prior to filtering the samples. The powder treatment will be repeated twice, one sample will be filtered with a paper coffee filter as it is transferred to the sterile bottle, the other sample will remove the purified water by pouring it into the sterile bottle carefully so as not to pour any coagulated solid contaminants into the sterile bottle. Each one-liter sample will be treated or filtered according to each manufacturer’s instructions. The filtered water will be filtered directly into a sterilized one-liter bottle or the clean water will be decanted into the sterile bottle in the case of the powder treatment as described previously.

Each one-liter sample will be shaken, and a pipet will be used to create a microscope slide. The slide will be observed under a compound microscope and visible contaminants will be counted. A photo of each microscope slide will be captured. This will be repeated a total of 5 times for each one-liter sample. The average value will be obtained for all 5 trials. The results will be compared to determine how effective each treatment is at purifying the water sample. Data and images will be compiled into an excel sheet and graphically analyzed.

Research will be conducted to determine the effectiveness of three categories of small-scale water filters. Three water treatment systems were chosen based on their complexity and price-range. A powdered water purifier, which requires no device to purify water and is the cheapest of the three systems to be tested. A mid-range small filter device will be tested retailing around $30. And an expensive premium filter will be tested that retails for around $90. The treatment powder and mid-range filter have yet to be acquired and will need to be before the start of testing.

For testing the samples, a compound microscope will be utilized to take before and after images. This microscope and related equipment will need to be acquired before the start of testing. A full procedure for acquiring, testing, filtering, and analyzing samples will need to be researched and will be described in detail in the methodology section. A basic plan of procedure is as follows: a large water sample (a minimum of a few gallons) will be collected from a natural source. (pond, river, etc.) This untreated sample will be stirred and analyzed via a microscope. This data will be extrapolated to estimate the number of contaminants in the water before treatment. This will be repeated, and an average value will be obtained.

After stirring the raw water sample, a 1-liter sample will be treated by each system in accordance with its manufacturer’s specifications. The samples will be analyzed via a compound microscope and any contaminants will be counted. This will be repeated at least 5 times per 1 L sample so an average value of contaminants can be obtained for each sample. Before and after photos will be captured of the untreated water and the 5 test samples from the treated water for each system. This will allow a visual comparison as well as a numerical statistic.

 An Investigation into the Effectiveness of Low-Cost Water Purification Systems

Introduction

            Across the Planet, the direst of needs is access to clean, safe, drinking water. Life cannot be sustained without water. The developed world has been blessed with constant access to safe drinking water, but for large portions of the planet, this is a far-off fantasy. Fortunately, recent years have brought forward massive advances in water filtration systems that are small, personal, and low-cost. But just how effective are these systems?

Many companies have developed solutions to this problem such as LifeStraw, Sawyer, Proctor & Gamble, and other popular sporting goods brands. Each system varies in price, complexity, and how and what they filter from the water. This investigation will collect water samples from a natural source and analyze them before and after treatment.

Three different purification systems will be tested: Proctor & Gamble’s (P&G) Purification Tablets, the Sawyer Mini Filter System, and an MSR Miniworks Ex Filter. These systems were selected due to their method of filtration and cost differences. P&G’s tablets force contaminants to separate from water allowing purified water to be decanted, this is the low-cost method. Sawyer’s Mini Filter system is intermediate in its price range and uses a hollow-tube filter membrane. MSR’s Miniworks Ex is a higher-cost filter that utilizes a ceramic core filter system. These systems do have limitations, they are designed for biological contaminants and are incapable of removing dissolved particulates, such as lead, viruses, or chemical contaminants.

Data collection will include water clarity, particulate count, and the presence of bacteria under microscopic evaluation. Results from testing will be used to compare the quality of filtration vs method of filtration and cost. This data will be useful in a wide variety of contexts. Foundations can use this data to determine what filter systems to donate to those in need. Those who spend a lot of time participating in outdoor activities can use this data to make purchasing decisions for personal water filters to use while hiking, camping, etc. Water filters are also useful emergency kit items and this data can convince people to place a filter in their kits.

Article detailing how LifeStraw works, the Sawyer Mini works similarly.

https://www.bbc.com/future/article/20180305-the-miraculous-straw-that-lets-you-drink-dirty-water

Article detailing P&G’s filtration packets and their importance to those in developing nations:

https://www.triplepundit.com/story/2019/pg-sets-new-goal-deliver-25-billion-liters-safe-drinking-water-worldwide/82916