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Crawlies Begone Category 1 Group: 1-018. Team Members: Leader: Shawn Chan 2I4 Choong Jun Mao 2I4 Anson Fong 2I4 Ivan Ong 2I3. Contents. Aim of Project Audience Background Research Methodology Other initiatives Bibliography. Aim of Project.
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Crawlies BegoneCategory 1Group:1-018 Team Members: Leader: Shawn Chan 2I4 Choong Jun Mao 2I4 Anson Fong 2I4 Ivan Ong 2I3
Contents Aim of Project Audience Background Research Methodology Other initiatives Bibliography
Aim of Project Investigate the properties of various natural cockroach repellents Find out the best type of cockroach repellent(In terms of effectiveness) Indirectly promote the use of environmentally-friendly cockroach repellents
Hypothesis Powdered Pandan leaves are the most effective repellent against cockroaches Traditional belief that Pandan leaves are good repellents against cockroaches Powdering can further expose the plant and intensify the smell
Audience Anyone and everyone who wishes for his homes/workplaces to be cockroach-free Environmentally-aware people who wants to prevent global warming
Background research So why are we doing this experiment?
Why cockroaches? Cockroaches feed on leftover food Unlike ants, they can also spread diseases They can cause dysentery and gastro-enteritis These diseases can be very serious or even fatal They also produce an offensive odour and can dirty the environment The Straits TimesApr 27, 2010 “Rojak seller to be charged”by Maria Almenoar
Insecticides (effect on environment) Over 98% of sprayed insecticides reach another unintended location Chlorofluorocarbons(CFCs) from the insecticides depletes the ozone layer More ultraviolet light is able to reach the earth Disturbs the many delicate ecosystems (Affects non-target species) It would take 50-100 years for theozone layer to repair itself again
Insecticides (health) Insecticides can enter the human body through many ways Harmful effects based on toxicity of the chemical and exposure The chemicals can accumulate in the body over time “Exposure can range from mild skin irritation to birth defects, tumours, genetic changes, blood and nerve disorders, endocrine disruption, and even coma or death” -Wikipedia
Survey A total of 25 people surveyed Q1. “Are you interested in having a natural repellent against cockroaches?”
Survey Q2. “How do you normally handle cockroaches in your household?”
Survey Q3. “What do you look for in cockroach repellents?”
The 8 natural repellents(Independent variable) Here are the natural repellents against cockroaches: • Pandan leaves • Lemon grass • Garlic • Lime • Cucumber • Basil leaves • Chilli pepper • Mentha(Mint plant)
Side Note So what is so unique about out project? Not only find out which repellent is the most effective Find out HOW it should be used to be even more effective E.g. If basil leaves are proved to be the best repellent, we will test if it is better powdered, juiced or moist
The cockroaches • American cockroach • German cockroach • Oriental Cockroach
Why American/ German cockroach Health reasons/ Safety(Oriental cockroaches are only found in garbage dumps/ very unhygienic place Commonly found(Wet markets/ Homes) Size(Up to 25mm, ideal for small set-up)
Methodology 1 (The main experiment) Independent variable: Type of repellent used Dependent variable: Number of cockroaches Fixed variables: Location, amount of peanut butter, amount of repellent, type of cockroaches, state of repellents Materials:1 plastic box w/ divider1 jar of peanut butter 5 American cockroachesA plastic sheet100g of each repellent
Methodology 1 (The main experiment) 1) Place the divider in the plastic box 2) Apply peanut butter to the center of one side of the box 3) Place 100g of the repellent in front of the peanut butter 4) Place the cockroaches in the middle of the box 5) Wrap the top with a plastic sheet to prevent cockroaches from escaping
Methodology 1 (The main experiment) 6) Wait for 15 mins 7) Record the number of cockroaches the repellent manages to repel 8) Repeat the experiment once more 9) Clean out everything in the box 10) Begin from step 1 again with a different repellent
So how do we compare the repellents? Unlike previous projects, we will not carry out the experiment like this: Repellent 1 Cockroaches released here Plastic Box Repellent 2 Divider (access at the bottom for cockroaches to pass through)
So how do we compare the repellents? Affect the results of the experiment Presence of 2 repellents will confuse the cockroaches Extreme scenarios
Set-up Plastic Box Repellent Cockroaches released here Peanut Butter Divider (access at the bottom for cockroaches to pass through)
Example Plastic box Peanut butter(bait) Repellent Plastic sheet Divider w/ hole
So how do we compare the repellents? Conduct experiments separately Compare the 2 repellents by comparing the number of cockroaches they repel and base their effectiveness on that E.g. Cucumber repels an average of 3 cockroaches, chilli pepper repels an average of 4 cockroaches. Chilli pepper is thus more effective
Control The control has a set-up with no repellents Peanut butter placed on one side while other side does not have any Ensures that the peanut butter is able to attract the cockroaches Also serves as a marking point to show how many cockroaches can be attracted at first
Control Plastic Box Cockroaches released here Divider (access at the bottom for cockroaches to pass through) Peanut Butter
Results Number of cockroaches repelled on average:Control: 2.5 out of 5Lemon grass: 3 out of 5Cucumber: 2.5 out of 5Pandan: 3.5 out of 5Mint: 3 out of 5Lime: 2.5 out of 5Garlic: 3.5 out of 5Basil: 3 out of 5Pepper: 3 out of 5 -Mint Leaf
Conclusions Almost all the plants possessed repellant properties(or at least did not attract cockroaches instead) Cucumber and lime are the least effective Pandan leaves and Garlic are the most effective in repelling cockroaches
Second phase of experiment Using Pandan leaves and garlic, we would find how they should be applied in order to become more effective The above experiment is repeated The only change is that the independent variable is changed to the state of the repellent
Results of second phase Number of cockroaches repelled on average: PandanPowdered: 4Watered: 2.5Juiced: 3.5 GarlicPowdered: 3.5Watered: 2Juiced: 4 - Pandan leaves (watered)
Results of second phase Powdering Pandan leaves will make it more effective Able to repel highest number of cockroaches at 4 Watering Pandan leaves will cause it to lose some of its repellant properties Fell from original marking point of 3.5 to 2.5
Results of second phase - Garlic (powdered)
Results of second phase Juicing/ Blending Garlic will make it more effective Able to repel a total of 4 cockroaches Like Pandan leaves, watering garlic will cause it to become less effective Dropped from repelling 3.5 cockroaches to 2
Final Conclusions Powdered Pandan leaves and juiced garlic are the best repellents against cockroaches Both are tied at a max. average of 4 cockroaches Watering/ Moisting any repellent causes it to lose its repellant properties Our hypothesis stood half-correct
Limitations Our experiment may not be very accurate Smell of certain repellents can still linger in the air even after box is cleaned Cockroaches may have already been badly affected by repellent
Methodology 2 (Alternative experiment) Independent variable: Type of repellent used Dependent variable: Distance of cockroaches from repellents Fixed variables: Location, amount of peanut butter, amount of repellent, type of cockroaches, tubing used Materials: 100g of each repellentAround 3 cockroachesA jar of peanut buter2 plastic 6cm diameter tubing(transparent)2 rubber stoppersMarkerMeasuring tape
Methodology 2 (Alternative experiment) 1) Attach the 2 rubber tubing together 2) Place a small amount of repellent in one end of the tubing and apply some honey in front of it 3) Cover that end of the tubing with a stopper 4) Place the cockroaches in the tubing through the other end 5) Quickly cover the end with the second stopper 6) Poke a small hole at the end of the tubing opposite the repellent to allow ventilation for the cockroaches
Methodology 2 (Alternative experiment) 7) Wait for 15 mins Honey Repellent Poke hole here Stopper Cockroaches Stopper
Methodology 2 (Alternative experiment) 8) Using a marker, mark out the position of the cockroaches nearest to and furthest from the repellent 9) Measure the distance from the repellent and calculate the average 10) Repeat the experiment 11) Continue the experiment with different repellents The best repellent would repel the cockroaches at the greatest distance
Methodology 2 (Alternative experiment) Another great way to test for efficiency of repellents More accurate because it tests to what extent the cockroaches can be repelled Can effectively retain smell inside or prevent outside gas from entering the rubber tubing Easy to remove cockroaches
Bibliography Wikispaces “Environmentalimpact of pesticides” June 2011 http://en.wikipedia.org/wiki/Environmental_effects_of_pesticides Answers “How do chlorofluorocarbons affect the Earth's ozone layer?” May 2011 http://www.answers.com/topic/how-do-chlorofluorocarbons-affect-the-earth-s-ozone-layer Robert S. Tennerman“Roach Repellent” May 2011 http://ezinearticles.com/?Roach-Repellent---5-Ways-To-Keep-Cockroaches-Out-Of-Your-Home&id=1039273
Bibliography Hwa Chong Institution (High School) Projects Competition 2009“Bio-Repellent”by Ivan Lim 2O3, AngHua Shine 2O3, Lee Han Ying 2O3, Aloysius Low 2O3 Hwa Chong Institution (High School) Projects Competition 2010“Household Ant Repellents”by Ong Yu Hann 1I4, Xu Shi Guang 1I4,Clarence Tan 1I3