Republic of the Philippines

Department of Education
Region III
​ Schools Division of City of Balanga
BALANGA CITY NATIONAL SCIENCE HIGH SCHOOL
Phase III, Talisay, City of Balanga, Bataan
___________________________________________________________________________

Meowsquitorminator: Assessing the Optimal Concentration for a Catnip Oil-Based Insect

Repellent

A Research Proposal

Presented to the Faculty of

Balanga City National Science High School

In Partial Fulfillment of the

Requirement for the Subject

Research I

By

Herrera, Kenji Mari

Artificio, Clare

Bustamante, Vonn Akisha Mari

1
Ochoa, Michaella Czyrene

Chavez, Jessica Lianna

Manalad, Erin Lianna

Ortega, Achilles Jeremy

De Vera, Yelleina

2025

2
 CHAPTER I
THE PROBLEM AND IT'S BACKGROUND
Introduction

Diseases and Harm caused by Mosquitoes—more specifically by the Aedes Aegypti—is

one of the biggest problems faced by people globally. Mosquitoes cause all types of illnesses.
Among these are; Malaria, dengue fever, West Nile virus, chikungunya, Zika fever, and
filariasis—particularly in tropical and subtropical areas. Due to the lack of efficient conventional
control, these diseases continue to spread widely and are the main causes of morbidity and
mortality in endemic areas (Minwuyelet et al., 2023).

A minimum of $94.7 billion (in 2022 US dollars) was the total calculated by a global
review of the economic expenses of mosquito-borne diseases over a 45-year period across 166
nations and territories. The actual financial cost of these illnesses is probably still undermined by
this estimate, though. In fact, Since then—This amount has increased by 14-fold, with yearly
expenses reaching $3.1 billion and reaching a record of $20.3 billion in 2013. Only a small
portion of the money spent on preventives was used to offset these economic losses and
damages, which outstrips the investments made in control measures. This proves that the need
for efficient control measures to lessen the increasing negative effects of chronic illnesses on
health and the economy is necessary. (Science of the Total Environment, 2024).

The Philippines is one of the many countries impacted by Mosquito-borne diseases,

especially dengue, due to its tropical climate. According to a report by The Department of Health
(DOH) there were 62,313 dengue cases from January 1 to March 1 2025, which is a 73%
increase compared to the same period the previous year. CALABARZON (12,735 cases), the
National Capital Region (11,291), and Central Luzon (10,185 cases) had the most cases
combined. (PNA, 2025.)

3
 According to the National Institutes of Health, mosquitoes can detect humans through
skin odor. Samuel Gertler of the US Department of Agriculture discovered a way to disturb a
mosquito’s sense of smell with the use of N,N-diethyl-3-methylbenzamide (DEET). In 1946,
insect repellents (IRs) in the form of cream, lotion, or powder which could alter olfactory
responses in mosquitoes were introduced. Since ancient times, people have taken herbal
precautions against mosquitoes to protect themselves. Nowadays, IRs exist to lower the risk of
being bitten by a mosquito. They are the first line of defense against biting arthropods and the
diseases they can transmit to humans and animals (Coats et al., 2021). Cost effectiveness,
availability, and high efficiancy against insects are ideal characteristics of a quality insect
repellent (Hebert et al., 2023). Picaridin, IR3535, oil of lemon eucalyptus, oil of citronella, and
2-undecanone are other Environmental Protection Agency–registered IR ingredients.

There are two kinds of Insect repellents: Natural and Synthetic. A Natural insect repellent
is a substance that keeps away insects that are usually from nature, mainly plants. A popular
natural insect repellent is Citronella, a widely effective repellent with a low level of toxicity in
humans; it is from the Cymbopogon nardus plant (Millar, 2023). Since natural repellents are
naturally made, synthetic repellents are man-made and formed chemically it is highly effective,
but due to the fact that it has hazardous effects and it affects other living organisms, more
attention is given to repellents with natural products (Chinthaka et al., 2023). A common
synthetic repellent is N,N-diethyl-m-toluamide (DEET), that was created in 1957 where it was
then labeled the "Gold Standard" of insect repellents (Repellents – Synthetic – Sutter Yuba
Mosquito & Vector Control District, n.d.).

People have already used plants and herbs as a precaution against mosquitoes since
ancient times. Despite chemical repellents being popular, there has always been a trend towards
producing and commercializing plant-based insect repellents in recent years (Turan & Çokyi̇ Ği̇ T,
2023). This popularization is due to the search for effective, healthier, safer, and eco-friendly
natural solutions since chemical repellents have been found to cause serious health problems.
The most common way of making a natural insect repellent from plants is using their essential

4
oils. The most popular option for plant based repellents is a plant in the citronella genus
Cymbopogon nardus, it is said to have a 100% repellency effect against Anopheles culicifacies
for up to 11 hours (Wangai et al., 2020).

Nepeta cataria, generally known as catnip or catmint, is a flowering plant in the genus
Nepeta of the mint family (Lamiaceae), that has long garnered the attention of researchers due to
its numerous benefits and potential applications. The name “catnip” came from the plant’s
positive behavioral effects on many cats when they inhale it. They show signs of attraction to the
plant, thanks to the presence of a chemical compound called nepetalactone. As a result, catnip is
commonly used in the pet toy industry, specifically for cats. However, the applications of catnip
are not limited only to attracting cats. Nepeta cataria var. Citriodora, or lemon catnip, is an
aromatic herb that possesses a lemon-mint flavor and resembles true catnip but does not elicit a
reaction from cats. This variant is used as raw material in the food industry and cooking. When
prepared as tea it is a sedative and soporific, while in cooking, it is used for its fragrance
(Aćimović et al., 2021). Additionally, research has proven that catnip shows promise as an insect
repellent also due to the compound nepetalactone, which works effectively to repel insects such
as mosquitoes (Batume et al., 2024).
​

Nepetalactone is a volatile oil, specifically a terpene that is found in Nepeta cataria.

According to Lichman et al. (2020), it is responsible for the euphoric or “high” response in cats
when they smell it, making it a natural cat attractant. Nepetalactone is present in Nepeta species
to protect against herbivorous insects, not to attract cats, which makes this compound a viable
insect repellent that is comparable to N,N-diethyl-3-methylbenzamide (DEET), also stating that
it may be better than DEET. According to Melo et al. (2021), Nepetalactone repels mosquitoes
by targeting the TRPA1 receptor in mosquitoes. The TRPA1 receptors are responsible for the
immune and inflammatory responses and in the conversion of physical and chemical stimuli in
irritative (itching) or pain sensations (De Araujo et al., 2020).

5
 The difference between Catnip and DEET which is the “Gold Standard” of mosquito
repellents. Based on a study by Shi et al., 2021, Catnip was found more effective than DEET in a
span of 24 hours but DEET was more effective than Catnip in 72 hours. It was found that catnip
oil has developed two cultivars which are called CR3 and CR9. CR3 contains 63.4%
E,Z-nepetalactone and 27.5% Z,E-nepetalactone and CR9 has 94.9% Z,E-nepetalactone. The
study compared CR3 and CR9 At 10% concentration, CR3 and CR9 showed repellency of 94%
for the first 8 hours. At 25% concentration CR3 and CR9 increased by 100% and DEET was at
92% repellency during the first 24 hours. After being aged for 3 days, CR3 and CR9’s repellency
was found to be less effective than DEET at 25% concentration. After aging for 28 days they
observed that the repellency of CR3, CR9, and DEET was reduced to 25%, 64%, and 92%
respectively. .
In this study, we aim to make a mosquito repelling spray with Nepetalactone as the active
ingredient, named the Meowsquitorminator, and compare different concentrations of Catnip Oil
in a spray solution. We will compare by measuring repellency duration and mosquito deterrence
rate. Furthermore, we will observe its potential environmental impact of nepetalactone compared
to other repellents.

The possible challenges to be considered in this study include the availability of the
ingredients of the said repellent, as we will have to find a supplier that will provide us with the
materials and ingredients we need for our product. Another hurdle would be ensuring the
product's long-lasting protection, as many natural repellents are volatile, meaning they break
down quickly in air, heat, and light, making it a challenge to formulate a long-lasting repellent.
Minimizing the impact of the repellent on the environment and human health as much as
possible will also pose a probable obstacle, as most insect repellents are toxic and harmful to the
human body, causing allergic reactions or skin irritations, and to other organisms. However,
despite these limitations, this paper will highly contribute to the development of future studies
that will also tackle the formulation of products that use natural repellents as their ingredients,
and possibly encourage other researchers to produce more effective repellents in the future.

6
Statement Of The Problem

​ Given the demand for better and greater alternatives, our study aims to examine the
effectiveness of Nepetalactone (the active compound in Nepeta cataria), as the primary
ingredient in our insect repellent spray—Meowsquitorminator.

Specifically, this research aimed to answer the following:

1.​ How different concentrations of Nepetalactone affect the repellent’s efficacy in
terms of:
a.​ Repellency duration? - How long the repellent remains effective before
mosquitoes return.
b.​ Mosquito deterrence rate? - The percentage of mosquitoes that avoid the
treated area.
c.​ User safety? - Potential discomforts and health effects towards the user

Significance Of The Study

This study is important in exploring the effectiveness of Nepetalactone, a natural

mosquito repellent as an alternative to DEET (N,N-diethyl-m-toluamide), a synthetic repellent
widely used for repelling insects such as mosquitoes that is known to have harmful effects on
both human health and the environment. This research focuses on addressing the widespread
mosquito problem at Balanga City National Science High School where mosquitoes pose a
serious health threat.
This study aims to benefit the following:

Students and School Staff: The outcome of this study offers a more accessible
alternative for individuals, presenting a solution that makes Meowsquitorminator
user-friendly and readily available to a wider audience. The primary focus of this study

7
 are the students and school staff, that targets on reducing the number of mosquito bites
within the school.

Environment: Most mosquito repellents are often composed of chemical

ingredients that can have harmful effects on both the environment and human health.
However, with the innovation of meowsquitorminator, these harmful effects can be
reduced. As a result, these help preserve natural ecosystems while effectively keeping
mosquitoes away.

Health Protection: This study aims to help local health authorities implement
safer mosquito control measures that are essential in preventing outbreaks of
mosquito-borne diseases. This research promotes the reduction of chemical pesticide use,
adapting more sustainable pest control practices without interfering with the ecological
balance of the ecosystem.

Future Research: Future researchers may find crucial points in this research, as it
provides a reference and an insightful preview of the study. This ensures that the topic
continues to evolve and remains relevant in future academic discussions. Researchers
may build on this study to investigate the effectiveness of different natural compounds in
repelling mosquitoes.

Local Communities: The local community surrounding Balanga City National

Science High School may also suffer from mosquito infestations, given the high
mosquito population in the area. This research proposes a community-wide solution to
mosquito control.

Scope And Limitations

8
 The study will be conducted in Balanga City National Science High School, and
the participants are the Grade 10 Students of Balanga City National Science High School.
The extent of the study compares concentrations of Nepetalactone in insect-repelling
solutions, finding out which is more efficient, and evaluating user safety. However, this
study excludes the comparison of Nepetalactone to other repellents and its environmental
impact.
​
The weakness of this research are the challenges that come with it. Since it is a
small scale research and accumulated in one specific school, we are not sure if it is
enough for production. There are also times where there are no classes, so there will be a
hindrance to the regular testing of Insect repellents. This study excludes the comparison
of Nepetalactone to synthetic chemical-based repellents and its possible environmental
impacts as this research will only focus on testing the duration of repellency and
effectiveness between different levels of concentration.

Definition Of Terms
Olfactory System - the sensory system responsible for the sense of smell

Olfaction - the ability to perceive airborne chemical stimuli at a distance from their source,
primarily through the olfactory system in the nasal chambers

Olfactory Epithelium - a specialized sensory tissue lining the roof of the nasal cavity,
responsible for detecting odors and transmitting signals to the brain

Arthropods - a group of invertebrate animals found in land or/and water. It is part of the phylum
Arthropoda which includes insects, spiders, mites, centipedes, crabs, and lobsters.

9
Insect Repellents - also referred to as “bug spray” is a substance used to prevent the transfer of
diseases like dengue and malaria. It can be applied to clothes or other surfaces to repel insects
and force them to fly or crawl away.

Natural insect repellent - repellents made from plant extracts (such as rosemary, peppermint,
holy basil, or tea tree) or oils (namely cinnamon oils, oil of lemon eucalyptus, or oil of
citronella). They are effective alternatives to chemical-based repellents and are designed to be
safe.

Citronella - According to the Merriam-Webster Dictionary, it is from two lemon scented grasses
namely Cymbopogon nardus or C. winterianus. Its oil is commonly used as a perfumer and
insect repellent.

Eucalyptus - It is defined by the Cambridge Dictionary as various types of trees specifically

found in Australia. Its oil produces a strong smell and is mostly used in the fields of medicine
and industry.

Synthetic insect repellent - Synthetic repellents are formulated with chemical compounds that
have been tested and proven highly effective in repelling insects. Ingredients used include DEET,
picaridin, IR3535, permethrin, allethrin,or malathion.

DEET - or N,N-diethyl-3-methylbenzamide has been considered the ‘gold standard’ for insect
repellent use since the 1950s and is found in most insect repellents available on the market to
prevent bites from insects like mosquitoes, biting flies, and flying insects. (Albers et al., 2024).

Nepeta cataria - Traditionally it is known as catnip or catmint and is a perennial herb from the
mint family Lamiaceae that strongly attracts most cats. This is often used as a safe attractant for
cats in the pet toy industry (Zeremski et al,. 2021).
Operationally, in this study, it is an insect repellent that is most effective in repelling mosquitoes.

10
Nepetalactone - The main compounds responsible for cats’ reaction to catnip. It can cause
euphoric effects to feline animals (Badshah et al., 2022).
Operationally, it is the main ingredient in the Meowsquitorminator which turns away mosquitoes
and other biting arthropods.

Terpene - Extracted from a series of plants, animals, and fungi, which show antiinflammatory,
antioxidant, and cytoprotective effects. They are widely used as a food additive and/or in
medicinal applications, however, it has potential harmful effects (Agus et al., 2021).

Pheromones- According to Merriam Webster,a chemical substance that is usually produced by

an animal and serves especially as a stimulus to other individuals of the same species for one or
more behavioral responses.

Allelochemicals- They are specific secondary metabolites that can exhibit autotoxicity by
inhibiting the growth of the same plant species that produced them.These metabolites have been
found to affect various physical processes during plant growth and development, including
inhibition of seed germination,photosynthesis, respiration, root growth, and nutrient uptake, with
diverse mechanisms involving cell destruction, oxidative homeostasis and photoinhibition (Xu et
al., 2023).

Volatile Organic Compounds (VOCs)- According to Minnesota Pollution Control Agency,

VOCs are a group of chemicals that can vaporize into air.

Receptor - chemical structures that receives and transduces signals.

TRPA1- It is expressed in both neuronal and non-neuronal cells and is involved in diverse
physiological activities, such as stabilizing of cell membrane potential, maintaining cellular
humoral balance, and regulating intracellular signal transduction. TRPA1 is a multi-modal cell
membrane receptor that can sense different stimuli, and generate action potential signals after
activation via osmotic pressure, temperature, and inflammatory factors (Yao et al., 2023).

11
Phytochemicals- According to the Science Direct, they are secondary metabolites of plants
which find application in human disease therapy.

Ecological Growth- An approach to development that takes into account ecological factors and
the need to conserve biodiversity and protect ecological systems.

Integrated Vector Management- According to WHO,(IVM) is a rational decision-making

process that encourages optimal use of resources for efficient, cost-effective and sustainable
vector control.

Felines-Plural form of Feline that means, a cat or other member of the cat family.

ANOVA,- According to Qualtrics, Analysis of Variance, is a test used to determine differences

between research results from three or more unrelated samples or groups.

Quantitative Research Design - is the process of collecting and analyzing numerical data. It is
commonly used to find patterns and discover relationships between two variables.

Experimental Research - a research method which compares two or more variables in certain
situations. It uses observations, simulations, and surveys.

Independent Variable - In an experiment, it is the variable that is changed or controlled.

Dependent Variable - In an experiment, it is the variable that is constant.

Questionnaire - a set of questions with provided choices. It is commonly used in surveys to

collect numerical data.

Steam Distillation - In this study, it is one of the processes to be used to extract the
nepetalactone from Catnip. It uses steam to separate the components.

12
Solvent extraction - Operationally, it is a process that will be used to extract the nepetalactone
from Catnip. It separates compounds through different solubilities.

Pearson’s Correlation - a statistical measure that focuses on the linear relationship between two
variables. It uses numbers between -1 to 1.
​

Notes In Chapter I

Philippine News Agency (PNA). (2025, March 19) 73% increase in dengue cases in early 2025.

https://www.pna.gov.ph/articles/1245853

13
Vax Before Travel. (2025, February 27). The Philippines reports 56 more dengue cases.

https://www.vax-before-travel.com/2025/02/27/philippines-reports-56-more-dengue-cases

Minwuyelet, A., Petronio, G. P., Yewhalaw, D., Sciarretta, A., Magnifico, I., Nicolosi, D., Di
Marco, R., & Atenafu, G. (2023). Symbiotic Wolbachia in mosquitoes and its role in
reducing the transmission of mosquito-borne diseases: Updates and prospects. Frontiers
in Microbiology, 14, 1267832

https://www.researchgate.net/publication/374683921_Symbiotic_Wolbachia_in_mosquitoes_and
_its_role_in_reducing_the_transmission_of_mosquito-borne_diseases_updates_and_pr
ospects

Science of the Total Environment. (2024). The rising global economic costs of invasive Aedes
mosquitoes and Aedes-borne diseases. Science of the Total Environment, 933, 173054.
https://www.sciencedirect.com/science/article/pii/S0048969724032017

Millar, H. (2023, March 31). 10 natural insect repellents to try.

https://www.medicalnewstoday.com/articles/natural-insect-repellent

Chinthaka, N. S. D. M., Delpagodage, N. C. J., & qqq Perera, N. a. G. W. U. (2023). A review on

the comparative analysis of synthetic insect repellents and essential oil based
sustained-release insect repellent formulations. Vidyodaya Journal of Science, 1(s1).
https://doi.org/10.31357/vjs.v1is1.6716

Hazarika, H., Krishnatreyya, H., Tyagi, V., Islam, J., Gogoi, N., Goyary, D., Chattopadhyay, P.,
& Zaman, K. (2022). The fabrication and assessment of mosquito repellent cream for
outdoor protection. Scientific Reports, 12(1).
https://doi.org/10.1038/s41598-022-06185-9

Batume, C., Mulongo, I. M., Ludlow, R., Ssebaale, J., Randerson, P., Pickett, J. A., Mukisa, I.
M., & Scofield, S. (2024). Evaluating repellence properties of catnip essential oil
against the mosquito species Aedes aegypti using a Y-tube olfactometer. Scientific
Reports, 14(1). https://doi.org/10.1038/s41598-024-52715-y

14
Aćimović, M., Zeremski, T., Kiprovski, B., Brdar-Jokanović, M., Popović, V., Koren, A., &
Sikora, V. (2021). Nepeta cataria–cultivation, chemical composition and biological
activity. Journal of Agronomy, Technology and Engineering Management (JATEM),
4(4), 620-634.

https://fiver.ifvcns.rs/bitstream/handle/123456789/2344/2021_nepeta.pdf?sequence=1&isAllowe
d=y

De Araujo, D. S. M., Nassini, R., Geppetti, P., & De Logu, F. (2020). TRPA1 as a therapeutic
target for nociceptive pain. Expert Opinion on Therapeutic Targets, 24(10), 997–1008.
https://doi.org/10.1080/14728222.2020.1815191

Demirak, M. Ş. Ş., & Canpolat, E. (2022). Plant-Based Bioinsecticides for mosquito Control:
Impact on insecticide resistance and disease transmission. Insects, 13(2), 162.
https://doi.org/10.3390/insects13020162

Lichman, B. R., Godden, G. T., Hamilton, J. P., Palmer, L., Kamileen, M. O., Zhao, D.,
Vaillancourt, B., Wood, J. C., Sun, M., Kinser, T. J., Henry, L. K., Rodriguez-Lopez, C.,
Dudareva, N., Soltis, D. E., Soltis, P. S., Buell, C. R., & O’Connor, S. E. (2020). The
evolutionary origins of the cat attractant nepetalactone in catnip. Science Advances,
6(20). https://doi.org/10.1126/sciadv.aba0721

Melo, N., Capek, M., Arenas, O. M., Afify, A., Yilmaz, A., Potter, C. J., Laminette, P. J., Para,
A., Gallio, M., & Stensmyr, M. C. (2021). The irritant receptor TRPA1 mediates the
mosquito repellent effect of catnip. Current Biology, 31(9), 1988-1994.e5.
https://doi.org/10.1016/j.cub.2021.02.010

Turan, N. Y., & Çokyi̇ Ği̇ T, M. A. (2023). A REVIEW OF PLANT-BASED INSECT

REPELLENTS, THEIR APPLICATIONS ON TEXTILES AND REPELLENCY TEST
METHODS. Usak University Journal of Engineering Sciences, 6(1), 33–51.
https://doi.org/10.47137/uujes.1251760

15
Wangai, L. N., Kamau, K. K., Munyekenye, G., Nderu, D., Maina, E., Gitau, W., Murigi, M.,
Kamau, S., Njuguna, M., Gichuki, J., & Otieno, F. (2020). Efficacy of plant-based
repellents against anopheles mosquitoes: a systematic review. Biomedical Sciences,
6(3), 44. https://doi.org/10.11648/j.bs.20200603.11

Aćimović, M., Zeremski, T., Kiprovski, B., Brdar-Jokanović, M., Popović, V., Koren, A., &
Sikora, V. (2021). Nepeta cataria – cultivation, chemical composition and biological
activity. https://fiver.ifvcns.rs/handle/123456789/2344

Srivastava, A., Gupta, S., Singh, S., Verma, R. S., Srivastava, R. K., Gupta, A. K., & Lal, R. K.
(2021). Genetic Variability and Elite Line Selection for High Essential Oil and
Nepetalactone Content in Catmint (<i>Nepeta cataria</i> L.). American
Journal of Plant Sciences, 12(07), 1135–1154. https://doi.org/10.4236/ajps.2021.127079

Fazil, H., & Porwal, O. (2022). Catnip (Nepeta cataria L.): Recent advances in pharmacognosy,
cultivation, chemical composition and biological activity. Journal of Drug Delivery &
Therapeutics, 12(4-S), 254-263.

Mapossa, A. B., Focke, W. W., Tewo, R. K., Androsch, R., & Kruger, T. (2021).
Mosquito‐repellent controlled‐release formulations for fighting infectious diseases.
Malaria journal, 20, 1-33.

Yao, K., Dou, B., Zhang, Y., Chen, Z., Li, Y., Fan, Z., Ma, Y., Du, S., Wang, J., Xu, Z., Liu, Y.,

Lin, X., Wang, S., & Guo, Y. (2023). Inflammation—the role of TRPA1 channel.

Frontiers in Physiology, 14. https://doi.org/10.3389/fphys.2023.1093925

16
 CHAPTER II
THEORETICAL FRAMEWORK

Relevant Theories

The first theory that significantly impacts this research is Chemical Communication
Theory. Insect behaviors mostly rely on the detection of chemical cues and signals, from finding
a mate to choosing a habitat and nesting site (Lucas et al., 2022). This principle states that
semiochemicals are used by organisms to interact with members of the same species using
pheromones and in sending chemical signals between creatures of different species with
allelochemicals. These semiochemicals can act as an attractant or repellent by modifying
behavioural patterns in insects at the desired time.

Additionally, a variety of volatile organic compounds (VOCs) are released by plants as a

response towards environmental cues. These chemicals shape the interactions between insects
and plants. The semiochemicals can be modified to have opposing effects on specific insects
only. Therefore, the techniques in maximizing the potential of plant semiochemicals to be used in
pest management are being explored.

17
 Next is the Receptor Theory that talks about the relationship between the dose and
response. It was first introduced in the 20th century by Langley and Ehrlich. This principle
explains how receptors that are distributed throughout the body detect internal and external
environmental changes which are then passed to the central nervous system for a response.

Additionally, it states that the biological effects of solutions are closely related to the
chemical concentration. In a graph about concentration-response by McGraw-Hill Medical, the
concentration is plotted against the percent maximal effect. This shows that there is a direct
relationship. If there is an increase in concentration then there will be an increase in the
biological response until the maximum response is reached.

Lastly, another theory that serves as a guide for this research is the Shape Theory of
Olfaction. Also known as the lock-and-key theory proposes that the olfactory system can

18
distinguish different odors based on the shape and size of their molecules. According to Terry in
2023, the molecules present in odor takes a certain shape that fits into a corresponding receptor
in the olfactory epithelium, a part of the olfactory system responsible for humans and animals'
sense of smell. This process is sometimes referred to as the ‘one-receptor-to-one-neuron’
organization.

The ability to perceive a specific scent is through the olfaction process. When the odor
molecule sticks to the receptor, a sequence of chemical reactions occur, which is then converted
into an electrical signal sent to the brain. However, the olfactory system is quite complex and has
capabilities that are beyond simple shapes and sizes. In addition, there are other factors such as
vibrations of molecules, which can contribute to the odor.

This theory is also applicable to insects such as mosquitoes. Mosquitoes continue to be a

global health threat. A study in 2024 by Ocker et at., states that mosquitoes utilize olfaction
during the search for human victims. In addition, their sense of smell guides most of their
behaviors. Understanding mosquitoes’ olfaction can lead to new findings and ways to reduce the
spread of diseases like dengue fever and malaria. The shape of olfaction theory will serve as a
guide in the creation of an innovative insect repellent to increase its level of effectiveness on the
target insect.

19
Review of Related Studies (Foreign)
Catnip as an Alternative for Synthetic Mosquito Repellents

​ A research study examined catnip as a potential natural alternative to synthetic mosquito

repellents that are harmful to the people as well as the environment. According to the study,
catnip essential oil primarily contains nepetalactone, which acts as an effective natural mosquito
repellent. The results indicate that even at low concentrations (2%), catnip oil successfully
repelled over 70% of Aedes aegypti mosquitoes for up to four hours (Batume et al., 2024).
Human hands were used to imitate the presence of a person, as mosquitoes are attracted to
octenol (1-Octen-3-ol), a substance released by the human body. Different amounts of catnip
essential oil were tested to check how well it kept mosquitoes away. The goal was to determine
how well different dilutions of the oil could reduce mosquito attraction to prevent bites. These
findings suggest that catnip oil could be a natural, effective alternative to synthetic mosquito
repellents for preventing mosquito-borne diseases.

20
How Catnip is a safer alternative for DEET

A foreign study states that catnip can act as a natural insect repellent by targeting a
specific receptor called TRPA1 in insects. The receptor is crucial to how catnip works to repel
pests like flies and mosquitoes. The active ingredient in catnip called nepetalactone, is
responsible for this effect. When insects come into contact with catnip or nepetalactone, it
activates the TRPA1 receptor, avoiding the area. Catnip only affects the TRPA1 receptors in
insects, but not in humans (Melo et al.). Therefore, while catnip repels insects, it does not have
the same effect on people, making it safer for human use. The study shows that because catnip
works on insect TRPA1 without impacting human receptors, catnip could be a better alternative
to synthetic insect repellents like DEET, which is commonly used but could have bad side
effects. In the future, this research opens up the possibility of creating new insect repellents that
are both effective at keeping pests away and safer for humans. By using natural ingredients like
catnip, this may reduce the need for harmful chemicals in insect repellents.

The Escalating Burden of Dengue Across the World

Through the years dengue is the most rapidly emerging mosquito-borne infection
worsened by climate change and urbanization. While dengue was mostly a childhood illness in
the past, it now primarily affects adults in many countries. Additionally, incidence of severe
cases and death rates from dengue are higher among pregnant women and individuals with
pre-existing health conditions comorbidities (Malavige et al., 2023). Despite the fact that new
mosquito control methods offer hope, there is still an urgent need for effective solutions to fully
reduce the impact of the disease. The study aims to provide better prevention strategies to control
the speed and reduce serious outcomes, which leads to the innovation of repellents such as catnip
which is herbal and beneficial for people who suffer from the illness.

Plant-Based Essential Oils as Natural Mosquito Repellent

21
 A study conducted in 2022 talks about herbal mosquito repellent to avoid diseases like
dengue, yellow fever, and malaria. However, the study highlights the drawbacks of synthetic
repellents, which can harm both human health and the environment. The focus of the study is on
plant-based repellents, specifically essential oils from various plants. These oils contain
phytochemicals that are effective at repelling mosquitoes and have minimal side effects
compared to synthetic chemicals. The study emphasizes that plant-based repellents are safer for
humans and animals, and they are more environmentally friendly, as they are biodegradable and
non-toxic to non-target creatures. The aim of the study is to explore essential oils as natural
alternatives for mosquito control, due to their larvicidal and repellent properties (Salunke et al.,
2022).

Review of Related Studies (Local)

Organic Materials as an Alternative Mosquito Repellent

Mosquitoes are one of the dangerous species of animals in the Philippines and the
diseases that they bring are deadly, like Malaria and Dengue (Selosa et al., 2021).This study
offers alternative ingredients in mosquito repellents to lessen the pollution that comes with it.
Experimenting the effectiveness and possible side effects to our environment of natural and
synthetic repellent. In this study a form of reprocess is produced, since in the Philippines one of
the major problems is waste materials and to help our country practice proper disposal.This
study aims to be wiser and without spending much that also helps to our environment.

Impact of Ecological factors to Mosquito Diseases

Different types of diseases such as Chikungunya, Dengue and ZIKA virus are very
common. The secondary vector of this disease is the Aedes Albopictus in the country of
Philippines(Edillo et al., 2024).This research tests the effect of different ecological factors on the
diseases. This study aims to experiment in the selected barangays with a classification of

22
Highland and Lowland. The diseases have a high mortality rate in order to lessen it they study
different types of diseases according to the environmental factors.

The Effectiveness of Plant-Based as an Insect Repellent

In 2016 there is a widespread Dengue Virus in the Philippines and it is declared as the
dengue epidemic year. Efficacy of a solvent-free crude extract of lemongrass (Cymbopogon
citratus) and sugar apple (Annona squamosa) as an insect repellent this study tests the natural
plants if it is way more effective, its toxicity and the consumer’s preference (Mangubat et al.,
2022). The research stated that in their study the commercialized insect spray is way more
effective than the organic extract from lemongrass and apple. However, this needs to be
reformulated as observations of potential larvicidal activity. It will be reformulated to equate to
the concentration of mosquito spray effectiveness.

Testing the Difference of Natural Mosquito Repellents

There are numerous species of animals that are vectors of deadly bacteria and viruses
which are located in the Philippines. This study utilizes organic material such as Oregano Lemon
Grass with Virgin Coconut Oil as an environmentally friendly alternative to synthetic and
commercialized pesticides and insecticides. Although the process is quite complex as natural
materials are used to end the life of cockroaches, this is simply a more environmentally friendly
way which also promotes ecological growth and provides help to human health. The experiment
consists of 12 samples per treatment, sprayed 5 times after 12 hours (Nuay et al., 2023). The
findings revealed that there is no significant difference between Oregano and Lemon Grass with
Virgin Coconut Oil as insecticides against cockroaches.

Implications for Dengue Control Strategies

​ The study investigates the rising resistance of Aedes aegypti mosquitoes to commonly
used insecticides, including pyrethroids (permethrin, etofenprox) and DDT, in the National

23
Capital Region (NCR) of the Philippines, a region with one of the highest dengue rates in the
country (Angeles et al., 2023). This shows that resistance levels vary across different cities in the
NCR, with some cities exhibiting higher resistance to insecticides like deltamethrin, cyfluthrin,
and lambda-cyhalothrin. This resistance reduces the effectiveness of current mosquito control
methods that depend on insecticides to lower mosquito populations and prevent the spread of
dengue. The study calls for a reassessment of current vector control strategies. The study
suggests considering alternative methods such as rotating insecticides to prevent resistance, using
biological control methods like natural predators or microbial agents, and adopting Integrated
Vector Management (IVM), which combines multiple techniques for more effective mosquito
control. These changes are necessary to improve dengue control and public health in the region.

Review Of Related Literature (Foreign)

Origins of Catnip

Plants from the genus Nepeta lamiaceae are commonly known as catmint or catnip due to
the way they can alter the behavior of cats. Catnip affects two-thirds of domestic cats and many
wild felid species including lions, tigers, and ocelots and induces playful actions among these
cats (Lichman et al., 2020). The most common of which is Nepeta cataria which is commercially
available all around the globe. On top of its effects on felines, they are known for their medicinal
properties and insect repelling properties (Melo et al., 2021).

Nepetalactone
Nepetalactone was found in catnip, and it was the first compound to be identified that
elicits the specific response in cats (Bol et al., 2022). This compound is also responsible for its
insect repelling properties against mosquitoes, flies, ticks, mites, and other disease vectors, with
results comparable to the golden standard repellent DEET (Gomes et al., 2020).

How Nepetalactone Repels Insects​

​ ​ In a journal article by Melo et al. (2021), it was recently discovered that

24
Nepetalactone repels insects by directly activating fly and mosquito TRPA1 receptors. While
they trigger the TRPA1 receptors in mosquitoes and flies, nepetalactone has been found to not
trigger any TRPA1 receptors in humans. These receptors are involved in inflammatory and
immune responses in the body, as well as irritative (itching) and pain sensations (De Araujo et
al., 2020).

What Species Does Nepetalactone Target

Nepetalactone is a broad-acting insect repellent being able to repel multiple species of
mosquitoes, including Aedes aegypti (dengue mosquitoes), Anopheles gambiae (malaria
mosquitoes), and Anopheles coluzzi. Additionally, it deters a common species of fly, Drosophila
melanogaster (fruit fly), from laying eggs in treated substrates Melo et al., 2021). Furthermore,
nepetalactone also has the potential to deter the common bed bug, Cimex lectularius (Gomes et
al., 2024).

Commercial Use of Nepetalactone/Catnip Oil

Catnip oil was registered in 2008 by the Environmental Protection Agency (EPA) and is
used in 4 products in the US. These 4 products were stated to have 7 hours of protection and all
products have concentrations of 7-15% of catnip oil and are considered more favorable than
DEET products.(Nguyen et al., 2023).

Review Of Related Literature (Local)

​
Ongoing Health Concerns Regarding Mosquito-borne Illnesses in the Philippines

Dengue and other mosquito-borne illnesses remain a major health concern in the
Philippines with the government required to conduct projects and programs to raise awareness
about dengue for the prevention of the disease. However, a significantly large number of

25
respondents in the Philippines on surveys conducted between the year 2000 to April 2020
showed a negative attitude towards the preventive measures of dengue, claiming that it was not
possible and it was not their responsibility. The lack of compliance of these respondents is
caused by their belief that repelling or eliminating mosquitoes is far too difficult and unsafe,
considering the different methods used to eliminate mosquitoes and their living conditions. This
may suggest that our country needs to look for easier, more sustainable, and safer ways to repel
and eradicate mosquitoes.

Effectiveness of Organic Mosquito Repellents

Citronella and garlic extract were both tested for their effectiveness in repelling
mosquitoes. The citronella and garlic plants were both obtained from Mountain View College,
and the experiment was conducted where the growth of mosquitoes were common. The ANOVA
test was used to find a significant difference in the treatment, while the Tukey method was used
to determine the difference in the species of the mosquitoes. Results show that Citronella and
Garlic extract both worked effectively in repelling mosquitoes. Garlic extract was effective in
repelling mosquitoes due to its strong odor and sulfur-containing compounds, such as alicin, that
work effectively to deter mosquitoes. Similarly, the strong odor of citronella was the cause of its
effectiveness as a repellent, as this interferes with the mosquitoes' ability to locate food sources,
causing them to avoid the area where they sense a strong odor.

Effectiveness of Locally Sourced Organic Plants as Mosquito Repellents

Using locally sourced plants as mosquito repellents offers a solution to the issue of
expensive commercialized repellents, which customers struggle to afford. Using oregano and
lemongrass, both locally sourced plants, as mosquito repellents has been proven to be effective.
These two plants do not show much difference in their effectiveness as repellents when
compared. However, when infused together in the form of a candle, their effectiveness rate in

26
repelling mosquitoes reaches 100% within 15 minutes. These findings encourage the use of local
plants to prevent the attraction of mosquitoes, both as products or by simply having the presence
of these plants.

Nepeta cataria as a Mosquito Repellent and Insecticide

Nepeta cataria is a non-locally sourced plant popularly known as an attractant to cats. It

has also shown promise as a mosquito repellent. Catnip leaves that were powdered and mixed
into a candle were tested to study their effectiveness as a mosquito repellent. Results show that
containers with the catnip candle showed signs of repellency, demonstrating effectiveness.
Meanwhile, some containers with a lit catnip candle managed to kill the mosquitoes inside them.
This indicates that catnip, which is commonly used as an oil for repelling mosquitoes, also works
effectively in repelling mosquitoes in powdered form and even possesses the ability to kill
mosquitoes when integrated in a candle. (Rom et al. 2019).

Comparison Between Chemical-based and Organic Mosquito Repellents

The prices of commercial, chemically prepared insect repellents are considered expensive
in the Philippines because many households in the country use these repellents to keep
themselves safe from the possible dangers of certain insects, especially mosquitoes. This raised
the interest of many researchers to find a cheaper alternative to chemical-based mosquito
repellents using ingredients that can easily be found. Numerous plants have shown promise as
effective insect repellents, such as citronella, peppermint, and catnip, which are now widely used
to repel mosquitoes. With that, a comparison of chemical-based and organic repellents was
needed to determine which was more cost-effective.

Mosquitoes show a more immediate response to chemical-based mosquito repellents.

However, the organic mosquito repellent showed a longer effectiveness compared to the

27
chemical-based repellent. It is also important to take note that chemical-based repellents have a
more pungent odor in comparison to organic repellents. Results demonstrate that organic insect
repellents are proven to be more cost-efficient as common plant extracts may be used and are
considered safer and healthier for the environment.

Conceptual Framework

Hypothesis

H0 - The concentration of Nepetalactone used in Meowsquitorminator insect repellent

does not impact the product's effect against mosquitoes by any means of effectiveness such as
safety, deterrence rate and duration of repellence.

28
 Ha - The concentration of Nepetalactone used in Meowsquitorminator insect repellent
does impact the product’s effect against mosquitoes by any means of effectiveness such as safety,
deterrence rate and duration of repellence.
.

Notes In Chapter II

Nguyen, Q. D., Vu, M. N., & Hebert, A. A. (2023). Insect repellents: An updated review for the
clinician. Journal of the American Academy of Dermatology, 88(1), 123–130.
https://doi.org/10.1016/j.jaad.2018.10.053
Selosa, A. A. D., Atienza, J. K., Apostol, R. H., Cas, J. C., Ramboanga, S. G., & Salvador, K. M.
Banana peels as an alternative for chemical components in making mosquito repellent. SDCA
Student Research Journal, 6.

Edillo, F., Ymbong, R. R., Navarro, A. O., Cabahug, M. M., & Saavedra, K. (2024). Detecting
the impacts of humidity, rainfall, temperature, and season on chikungunya, dengue and
Zika viruses in Aedes Albopictus mosquitoes from selected sites in Cebu city,
Philippines. Virology Journal, 21(1). https://doi.org/10.1186/s12985-024-02310-4
Mangubat, F. M. (2022). Efficacy of a solvent-free crude extract of lemongrass (Cymbopogon
citratus) and sugar apple (Annona squamosa) as an insect repellent. Journal of
Agriculture and Technology Management (JATM), 25(1), 48-51.
Nuay, M. C., Buenavista, I. M., & Santos, A. D. S. D. Oregano (Origanum Vulgare) and
Lemongrass (Cymbopogon Citratus) Crude Extracts with Virgin Coconut (Cocos Nucifera) Oil:
Pesticide for American Cockroaches (Periplaneta Americana).

Angeles, J. R., Malijan, R. P. B., Apilado, A. M. A., Ammugauan, M. A. T., & Salazar, F. V.
(2023). Insecticide resistance in Aedes aegypti from the National Capital Region,
Philippines. bioRxiv, 2023-09.

29
Bol, S., Scaffidi, A., Bunnik, E. M., & Flematti, G. R. (2022). Behavioral differences among
domestic cats in the response to cat-attracting plants and their volatile compounds reveal
a potential distinct mechanism of action for actinidine. BMC Biology, 20(1).
https://doi.org/10.1186/s12915-022-01369-1
De Araujo, D. S. M., Nassini, R., Geppetti, P., & De Logu, F. (2020). TRPA1 as a therapeutic
target for nociceptive pain. Expert Opinion on Therapeutic Targets, 24(10), 997–1008.
https://doi.org/10.1080/14728222.2020.1815191
Gomes, E. N., Allen, K., Jaworski, K., Zorde, M., Lockhart, A., Besancon, T., Brown, T.,
Reichert, W., Wu, Q., & Simon, J. E. (2020). Catnip (Nepeta cataria L.): Recent
Advances in Botany, Horticulture and Production. In Medicinal and aromatic plants of
the world (pp. 247–284). https://doi.org/10.1007/978-3-030-44930-8_11
Gomes, E. N., Caputi, C., Patel, H. K., Zorde, M., Vasilatis, A., Wu, Q., Wang, C., Wyenandt, C.
A., & Simon, J. E. (2024). Chemical variability and insect repellent effects of lemon
catnip essential oil and related phytochemicals against Cimex lectularius L. Journal of
Natural Pesticide Research, 8, 100074. https://doi.org/10.1016/j.napere.2024.100074
Lichman, B. R., Godden, G. T., Hamilton, J. P., Palmer, L., Kamileen, M. O., Zhao, D.,
Vaillancourt, B., Wood, J. C., Sun, M., Kinser, T. J., Henry, L. K., Rodriguez-Lopez, C.,
Dudareva, N., Soltis, D. E., Soltis, P. S., Buell, C. R., & O’Connor, S. E. (2020). The
evolutionary origins of the cat attractant nepetalactone in catnip. Science Advances,
6(20). https://doi.org/10.1126/sciadv.aba0721
Melo, N., Capek, M., Arenas, O. M., Afify, A., Yilmaz, A., Potter, C. J., Laminette, P. J., Para,
A., Gallio, M., & Stensmyr, M. C. (2021). The irritant receptor TRPA1 mediates the
mosquito repellent effect of catnip. Current Biology, 31(9), 1988-1994.e5.
https://doi.org/10.1016/j.cub.2021.02.010
Mac Guad, R., Carandang, R. R., Solidum, J. N., Taylor-Robinson, A. W., Wu, Y. S., Aung, Y.
N., Low, W. Y., Sim, M. S., Sekaran, S. D., & Azizan, N. (2021). Different domains of
dengue research in the Philippines: A systematic review and meta-analysis of
questionnaire-based studies. PLoS ONE, 16(12), e0261412.
https://doi.org/10.1371/journal.pone.0261412
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0261412

30
Arcilla, F. E., Jr, Dumay, M. A., & Perdizo, G. Q. (2019). The Effectiveness of Citronella Extract
(Cymbopogon winterianus Jowit ex Bor) and Garlic Extract (Allium sativum) as
Mosquito (Culicidae) Repellant. https://ejournals.ph/article.php?id=14053
https://ejournals.ph/article.php?id=14053

Benaid, J. (2019, January 18). Utilization of indigenous plants as mosquito repellent.

https://ojs.aaresearchindex.com/index.php/AAJMRA/article/view/12123
Rom, K. a. J., Armesto, M. F., & Tanagras, P. (2019, January 18). Efficacy of Candles Made from
Powderized Catnip Leaf (Nepeta cataria) as a Natural Mosquito Repellent.
https://ojs.aaresearchindex.com/index.php/AAJMRA/article/view/4277
https://ojs.aaresearchindex.com/index.php/AAJMRA/article/view/4277

Elle, D. R. D., Jarlos, M. a. B., Macalalad, M. J. C., Muñoz, P. N. V., & Manaig, C. K. D. (2019,
January 18). Comparison between Chemical-based and Organic Mosquito Repellants.
https://ojs.aaresearchindex.com/index.php/AAJMRA/article/view/4061
https://ojs.aaresearchindex.com/index.php/AAJMRA/article/view/4061

31
 CHAPTER III
METHODOLOGY

Methods and Techniques of Research

This research study will be taking on a quantitative research design, specifically one of an
experimental research study to assess the effectiveness of different concentrations of catnip oil
towards mosquito repellency and repellency duration. The experimental method uses true
experiments or scientific methods for determining a cause-effect relation between variables. It
involves testing a hypothesis through experiments, in which one or more independent variables
are manipulated and then their effect on dependent variables are studied (Sreekumar, 2023). ​

​ This approach offers a crucial framework for evaluating our hypothesis and guaranteeing
the validity and reliability of the results. We can see how catnip oil affects mosquito repellency
and how long it works by methodically changing its concentration. By minimizing outside
factors that could affect the outcomes, the controlled experimental setup makes sure that any
effects are attributable to the manipulated independent variable.

Additionally, the experimental research design guarantees replicability, which means that
similar experiments can be carried out in the future to confirm our findings. This method
improves the study's dependability and advances our understanding of natural mosquito
repellents in general.

Material Quantity Description

Spray Bottle 100 ml Main compartment

Isopropyl Alcohol 68.75 ml Solvent

Catnip Oil 25 ml Solute

32
Witch Hazel Extract 6.25 ml Emulsifier

Table 1
List of materials that were used in the study in Trial 1

Material Quantity Description

Spray Bottle 100 ml Main compartment

Isopropyl Alcohol 37.5 ml Solvent

Catnip Oil 50 ml Solute

Witch Hazel Extract 12.5 ml Emulsifier

Table 2
List of materials that were used in the study in Trial 2

Material Quantity Description

Spray Bottle 100 ml Main compartment

Isopropyl Alcohol 6.25 ml Solvent

Catnip Oil 75 ml Solute

Witch Hazel Extract 18.75 ml Emulsifier

Table 3
List of materials that were used in the study in Trial 3

33
Locale

This research will be conducted at Balanga City National Science High School
(BCNSHS) and will focus on developing and testing a mosquito repellent made from catnip. The
study aims to determine the effectiveness of catnip’s natural compounds in repelling mosquitoes
to help prevent the spread of mosquito-borne diseases such as malaria, yellow fever, and dengue.
Through laboratory experiments, formulation trials, and field testing, this research seeks to create
a safe and effective alternative to synthetic mosquito repellents, promoting both public health
and environmental sustainability.
Research Instrument

The research instrument used in this study is a self-administered questionnaire that is

designed to evaluate the safety of the Meowsquitorminator. This questionnaire focuses on the
safety aspect of our product. The instrument consists of 5 items that assesses user safety which
focuses on how safe the product felt to use. It asks if there were any safety concerns, such as the

34
risk of irritation or injury while using the device. The goal is to understand if users felt safe while
using the product.

Respondents rate each item on a five-point Likert scale, ranging from 1 (Strongly
Disagree) to 5 (Strongly Agree), based on personal experience with the product. The
questionnaire is conducted between the Grade 9 Students of Balanga City National Science High
School guaranteeing that the test was experienced first hand and allow the researchers a quick
and convenient way to collect data from this questionnaire. This research instrument helps
evaluate Meowsquitorminator’s safety by gathering feedback. This data provides valuable
insights for improving the product and ensuring Meowsquitorminator meets user expectations,
making it safer for future users.

In addition to the questionnaire, observation will be used as a complementary research

tool. Observers will watch participants as they use the Meowsquitorminator in real-life
situations. They will note how well the product repels mosquitoes, how users interact with it, and
whether any safety issues arise during use. This observational data will provide additional
insights into the product's performance, offering a more complete picture beyond the responses
given in the questionnaire. By using both the questionnaire and observation, the study will gain a
better understanding of the Meowsquitorminator's effectiveness, ease of use, and safety.

​
​
Data Gathering Procedure

This study will follow quantitative research methods. A series of experiments will be
conducted until the desired result is achieved. The researchers aim to create an effective
mosquito repellent spray from Nepeta cataria, also known as “Catnip”.

The process will begin with the extraction of nepetalactone from Catnip. Using a type of
extraction technique called steam distillation will be used to obtain varying concentrations of
Nepetalactone, namely 25%, 50% and 75%. Then the extracted Nepetalactone from fresh, finely

35
chopped catnip leaves, will be mixed with boiling water and witch hazel extract or vodka to
enhance the repelling effect and give the spray a longer shelf life.

Once all the solutions have been created, an experiment will be conducted. Mosquitoes
will be trapped in two connected clear chambers where the solution will be sprayed in one of the
containers. This procedure will be repeated for each of the solutions with varying concentrations.

To accurately calculate the effectiveness of the repellent, each chamber will be labeled,
the same amount will be sprayed, and it will contain the same number of mosquitoes. In addition
it will be situated in the same area for the same amount of time. The researchers will count the
number of mosquitoes who will leave the treated container and go to the untreated chamber.
Their flight behavior in each compartment will also be observed. At the same time, the longevity
of the repellent can be tested by carefully monitoring and timing the mosquitoes’ movement.

Data Processing And Statistical Treatment

​

The data from the experiment will be processed systematically to ensure accuracy,
consistency, and reliability before statistical analysis. All observations (such as the number of
mosquito landings, flight pattern, and repellency duration) will first be recorded and tabulated in
a spreadsheet. Inconsistent or missing data will be verified and, if invalid, deleted. The
information shall be grouped under categories and then calculated for the descriptive statistics in
the form of mean, range, and standard deviation. After analysis, statistical tests such as One-Way
ANOVA and Pearson's Correlation will be used to test the differences between repellents in
correlation to nepetalactone concentration and repellency period.

For our study, several statistical formulas and measures are needed for gathering data.
These formulas include:

36
1. Central Tendency: The mean represents the average number of mosquito landings per
repellent type and concentration level

Sample Mean (𝑥̄): the average value of a dataset, which provides a central value around the data
points that are distributed. In other words, the average effectiveness of various concentrations in
catnip oil-based repellent

Formula:

Where:

𝑥̄ = Sample mean

x = number of mosquitoes landing per trial

n = Number total trials

Population Mean (μ): the average of all possible observations in the population—to collect data
from the entire population of interest.

Formula: :

Where:

​ ​ μ = Population mean

​ ​ x = No. of mosquito landing

37
​ ​ n = Total no. of trials in the population

Weighted Mean: the average of data points while considering the degrees of importance
(weights) of each point.

Formula:

Where:

​ ​ 𝑥̄ = Weighted mean

​ ​ w = Weight of each data point

​ ​ x = Each individual data point

Midrange: the midpoint between the maximum and minimum values in the dataset.

Formula:

Where:

highest value = Maximum value in the dataset

​ ​ lowest value = Minimum value in the dataset

2. Measures of Dispersion: calculates the spread of mosquito landings around the mean

38
 Sample Standard Deviation (s): the amount of variation or dispersion of a set of sample data
points from their mean.

Formula:

Where:

​ ​ s = Sample standard deviation

​ ​ x = No. of mosquitoes landing per trial

​ ​ 𝑥̄ = Mean of mosquitoes landing

​ ​ n = Total no. of trials

Population Standard Deviation (σ): the dispersion of all data points in the population from the
population mean.

Formula:

Where:

​ ​ σ = Population standard deviation

39
​ ​ x = No. of mosquitoes landing per trial

​ ​ μ = Population mean

​ ​ n = Total no. of trials

3. Inferential Statistics: To determine if there is statistically any difference in repellency

between the different concentrations and repellent types

One-Way ANOVA (Analysis of Variance): comparison of the means of three or more

independent groups to determine if at least one group mean is different from the others.

Formula:

Where:

F = F-statistic (variance ratio)

SSB/df Between = Variance among the group means

SSW/df Within = Variance within each group

Meaning, If F < 0.05, there is a difference in mosquito deterrence across different

concentrations.

Pearson’s Correlation Coefficient (r): the strength and direction of the linear relationship
between two variables, Pearson’s correlation will be used to determine the relationship between
Nepetalactone concentration and repellency duration.

Formula:

40
 Where:

​ ​ x = Nepetalactone concentration (%)

​ ​ y = Repellency duration (minutes)

​ x̄ = Mean concentration level

​ ​ ȳ = Mean repellency duration

r > 0: Higher Nepetalactone concentration leads to longer repellency duration.

r < 0: Higher Nepetalactone concentration decreases repellency duration.

r = 0: No relationship between concentration and repellency duration.

4. Cohen’s D: the standardized difference between two means

Formula:

Where:

​ M1 — M2 = Sample means

41
​ ​ Sp = Pooled standard deviation

5. Cronbach’s Alpha (α): calculates internal consistency of survey-based data for reliability

Formula:

Where:

​ ​ k = Number of items (survey questions)

​ ​ si²= Variance of each individual item

​ ​ sT² = Variance of the total score

Ethical Considerations

Our study aims to provide contributions in improving health safety by studying a

mosquito repellent that may have a reduced environmental impact while helping to prevent the
further spreading of mosquito-borne illnesses. However, there are ethical concerns that need to
be considered while conducting our study. While this can provide knowledge and contributions
for future innovations in creating more sustainable and safe mosquito repellents, conducting this
study may raise environmental concerns and potential harm to the subjects and the researchers.

42
 The compound Nepetalactone in Nepeta cataria works effectively as a repellent, not only
for mosquitoes. Conducting our experiment on mosquitoes in the wrong environment may
potentially drive away non-targeted species from their natural habitat causing a disruption in the
ecological balance of the ecosystem. To prevent causing ecological imbalance to local
ecosystems, the experiment will be conducted in an area away from any major insect habitats.
An enclosed mosquito rear cage will also be used to ensure that the fumes of the repellent do not
escape the enclosed space.

Ethical concerns in our study are unavoidable since the experimenting process requires
putting mosquitoes' lives in risk. Even if we are only testing on mosquitoes, this moral concern
must still be considered as this organism also plays an important role in the ecosystem, and its
life should still be recognized despite the negative impact it may cause. Ensuring that no
unnecessary cruelty will be used in keeping the mosquito test subjects is crucial since ethical
research standards require researchers to be humane to all living organisms and as this may also
alter the result of the experiment. The safety of the researchers must also be considered as
handling mosquitoes and handling the untested repellent may pose health hazards. Therefore,
using appropriate protective gear when handling mosquitoes is essential to avoid any serious
health risks.

Additionally, it is crucial to ensure that the catnip collection and oil extraction processes
do not negatively impact the environment. The catnip used for extraction must be ethically
sourced to prevent overharvesting. If the discarded remains of the catnip extraction process are
not properly disposed of, they may deter non-target species, potentially disrupting the balance of
the surrounding ecosystem. Proper disposal of solvents and catnip used in the extraction process
is important to avoid environmental impact and prevent pollution.

Notes In Chapter III

43
Sreekumar, D. (2023, March 22). What is Quantitative Research? Definition, Methods, Types,
and Examples. Researcher Life.
https://researcher.life/blog/article/what-is-quantitative-research-types-and-examples/

44