Electromagnetic (Microwave) radiation AND ITS Effect on plant and bacteria Growth By: Bryce mathews

Basic introduction to Microwaves A microwave heats up its contents by using “microwaves”, a form of electromagnetic waves, with a stronger frequency than radio waves. They cook food by invigorating particles inside of the item being cooked into vibrating faster and faster. This energy creates heat. Electricity reaches the microwave through the transformer. 3. The microwaves bounce around the inner chamber/ cooking cavity of the microwave much like light bounces off a mirror. 4. When the waves eventually come into contact with the item, they are absorbed and are used to create heat. This results in the purpose of the microwave; to cook your food. 2. The magnetron then takes this usable electricity, and converts it into microwaves.

Does microwave radiation have any negative effects on plants? Even fewer legitimate experiments have been performed to test how EMF (electromagnetic frequencies) affect plant growth. The common approach is; in plants, EMF has a drastic effect on a plant’s germination rates, its resilience, and its overall growth. It is said to absorb nutrients in the soil, and affect the roots of plants, lowering their ability to retract water. EMF ionized with water molecules can possibly create water that is harmful to plants. Few studies say that EMF may contribute to raising the pH of the water, being much more basic, or “Alkaline” than normal “neutral” water. Little to no studies have been found regarding EMF’s effect with bacteria growth.

Does microwave radiation have negative effects on microbes? Some sources claim that specific levels of radiation can denture bacterial growth. Some studies have shown that EMF can affect specific bacteria’s physiochemical properties and is said to cause hyperpolarization in other bacteria.

Project Background This experiment will use Radish plants, and E-coli bacteria to test whether EMF in the form of microwave radiation, has a significant effect on plant and bacterial survivorship, respectively. Seeds of radishes in groups of four will be microwaved in intervals of 5 (Zero being the control and 20 being the maximum time [for this experiment] exposed to radiation.) and planted inside of a small pot, where they will be watered every other day. E-coli will be mixed with water, then microwaved for the designated amount of time, then placed in a sterile petri-dish. Afterwards, the dishes (in groups of five according to the amount of time exposed) will be placed in an incubator to grow for a period of time. Basic safety measures need to be taken, especially when handling the E-coli, and the esterized rod. Clean-up and handwashing will also be incredibly necessary, to prevent the spread of E-Coli.

Purpose The purpose of this experiment is to determine whether EMF (Microwave radiation) has a significant effect on Radish plant growth, and bacterial survivorship.

Hypothesis Hypothesis: The Microwave radiation will have a significant effect on the survivorship of both the Radish and E- Coli. The longer the organism is exposed to radiation, the larger the significance of lower survivorship, or the more negative the effects are. Null Hypothesis The plants and bacteria will grow at their own pace and will have no interaction with the radiation whatsoever. There will be no significant decrease in survivorship when investigating the varying exposure times. Survivorship rates will not be able to be more significant than chance.

Materials Around 3-5 packets of Radish seeds (depending on the amounts of seeds in each packet) 10 small-medium sized pots Paper towels Measuring cup Potting soil Marker or pen (For recording data and marking pots and dishes) Notebook (For transferring data) Access to water Microwave Incubator 25 petri-dishes and sterile rods E-coli bacteria 5 15ml conical tubes(For mixing bacteria and water) Pipette Micro-pipette Items in the ORANGE box are materials needed to perform E-Coli experiment. Items in the GREEN box are materials needed to perform Plant experiment.

Procedure – Plant Experiment Radish seeds in groups of four were taken out of their packets (about 40 seeds are needed.) Two groups of four represent each interval of exposure. (8 seeds for 0 seconds, 8 seeds for 5 seconds, etc.) The pots were set up and filled with ½ cups of potting soil. Each group of radish seeds were microwaved on a paper towel for their designated amount of time. After each group was microwaved, they were placed in their own pots. Four seeds populated one pot. The pots were marked with the amount of time microwaved. (Zero seconds of exposure is the control of the experiment.) The plants were watered with ¼ cup of water at room temperature every other day, for 5 to 7 days. After the designated amount of days, measurements of height in centimeters were taken. Procedure – Bacteria Experiment Materials were gathered. The E-Coli stock was diluted to 10-cubed cups/ml in sterile water. The stock was placed in 5 conical tubes. Contents of tubes were sealed in with a cap, and mixed thoroughly by vertexing. Each tube of stock was marked according to their times (0-20 seconds), and microwaved for their designated times. When all of the tubes were microwaved, each tube was vortexed once more, placed in a case, ranged from lowest exposure time, to highest. All petri-dishes were marked, having five dishes per interval of exposure. (25 dishes in all() About 1ml of mix corresponding to the exposure time was pipetted into the center of the dishes with the same exposure time, and mixed throughout the dish carefully, and softly with a sterile rod. (Each lid was hardly lifted to avoid possible contamination when the mix was pipetted inside.) This process was then repeated for times 5, 10, 15, and 20. Different sterile rods were used for each petri-dish. Afterwards, the petri-dishes were placed inside of an incubator. Each item used was thoroughly cleaned/rinsed, and returned. After a day of incubating, the colonies were counted and measured.

More Radish data – Overall Averages Average plant size (CM)

Radish Data – SEM bar graphs Height of Radish plants (CM)

Plant Data – Anova Anova: Single Factor SUMMARY Groups Count Sum Average Variance O Seconds (Control) 8 11.5 1.4375 3.316964 5 Seconds 22.6 2.825 1.027857 10 Seconds 14.8 1.85 5.102857 15 Seconds 9.9 1.2375 1.154107 20 Seconds 10.9 1.3625 1.71125 ANOVA Source of Variation SS df MS F P-value F crit Between Groups 13.4065 4 3.351625 1.361007 0.267307 2.641465 Within Groups 86.19125 35 2.462607 Total 99.59775 39  

Radish Data – Dunnett's Test After performing the Dunnett’s test, the t-value equaled 0.0038 (or 0.004), while the T-crit equaled 4.044. (Since df = 39, and there are 5 groups, plotted on a 0.5 graph) This shows that this experiment failed to reject the null hypothesis.

Results – Radish Experiment After measuring and performing the Anova testing, evidence showed that the P-value was higher than the set number of 0.5. This along with the fact that the F-value is smaller than the F-Crit, (along with the Dunnett’s test) can say that there is not enough evidence to support that the hypothesis is correct.

Data – E-Coli Experiment Average temp. 22*C Average Temp. 38*C Number of Colonies

E-Coli Data - Anova Anova: Single Factor SUMMARY Groups Count Sum Average Variance 0 Seconds 5 216 43.2 57.7 5 Seconds 195 39 69 10 Seconds 43 8.6 47.3 15 Seconds 2 0.4 0.3 20 Seconds 32 6.4 204.8 ANOVA Source of Variation SS df MS F P-value F crit Between Groups 7985.84 4 1996.46 26.33157 1.01E-07 2.866081 Within Groups 1516.4 20 75.82 Total 9502.24 24  

Results – E-Coli experiment After examining the data, there was a significant decrease in survivorship with every increase in exposure. The EMF did have a an effect on the E-Coli, and that effect was negative. The P-value was also well below the 0.05 mark. The F-value is also larger than the F-crit. This proves that the null hypothesis was rejected; microwave radiation had a significant effect on the survivorship of the E-Coli.

Conclusion Given the data in regards to the bacteria, the data supported the given hypothesis. The data presented a near linear decline in survivorship as the exposure times increased. This data along with the Anova test presents that microwave radiation had a negative effect on the E-Coli, well beyond the limitations of chance. In the radish experiment, an Anova and Dunnett’s test was performed. When the Anova was completed, the P-value was higher than 0.5, the F-value was smaller than the F-Crit, and the Dunnett’s test showed that the T-value, being 0.004 was smaller than the T-Crit (being 4.044). This data shows that the experiment failed to reject the null hypothesis. More evidence would need to be gathered to reject the null.

Possible changes for future experiments and how this affects us. Better methods of handling, watering, positioning, and maintaining the plants could’ve been used. Possible contamination inside of the petri-dishes could’ve affected the E-Coli colonies in some way. Imprecise counting could’ve taken place, giving inaccurate numbers. By doing this experiment, we learn more about the effects of radiation on life all around us, from plants, to bacteria. By applying this to ourselves, we can learn about the possible damages that EMF can cause, and how it affects our daily lives. By experimenting, we learn how humans can be affected by the EMF we create, use, and absorb.

Bibliography http://www1.lsbu.ac.uk/water/magnetic_electric_effects.html https://www.floraldaily.com/article/9015802/how-does- electromagnetic-radiation-affect-plants/ https://www.education.com/science-fair/article/microwave- radiation-affect-different-organisms/ https://www.explainthatstuff.com/microwaveovens.html https://www.tandfonline.com/doi/abs/10.3109/09553002.2015.11015 00