INSECT REPELLENT CANDLE (PARAFFIN)
FROM TANGLAD (Cymbopogon citrates Stapf.) LEAF EXTRACT
ANGELICA ROSE ECLEVIA
Section FL 1
Submitted to
Mrs. Hazel Talip
City Central School
SY 2010 - 2011
ABSTRACT
Insect repellents help prevent and control the outbreak of insect-borne diseases such as malaria,
Lyme disease, Dengue fever, bubonic plague, and West Nile fever. Mosquitoes alone are estimated to
transmit disease to more than 700 million people annually in Africa, South America, Central
America, Mexico and much of Asia with millions of resulting deaths. DEET (or N,N-Diethyl-metatoluamide) remains to be the most common active ingredient in insect repellents worldwide. However,
because of its toxic property which poses health and environmental risks, efforts have been done on
developing better alternatives which are commonly essential oils from plants. Cymbopogon citratus,
commonly known as lemon grass or Tanglad, contains citronella oil which has been researched to be
comparably effective as an effective insect repellent with a non-toxic mode of action. This study assessed
the feasibility of creating an insect repellent candle from Tanglad leaf extract in paraffin wax. In the
experiment done, the lighted candle made has been observed to repel mosquitoes which the typical candle
has failed to do so. This study then concludes that the candle made is indeed feasible to be used as an
effective insect repellent.
TABLE OF CONTENTS
TITLE PAGE…………………………………………………….……………...…….…..………... i
TABLE OF CONTENTS…………………………………………………………….….…...……... ii
ABSTRACT…………………………………………………………………………...…...........….. iii
I.
INTRODUCTION…...………………………………………………………………..………1
a. Background of the Study…………………………………………...…………..…….. 1
b. Objectives………………………………………………………………………..……. 1
c. Scope and Limitations………………………………………………………………… 1
d. Review of Related Literature…………………………………..……………………... 1
II. METHODOLOGY…..…………………………………………..…………………………... 4
a. Materials………………………………………………….………………………........ 4
b. General Procedure…………………………………….…………………………….… 4
III. RESULTS AND DISCUSSION…..……………………………………………………….… 6
IV. CONCLUSION…………………..…………………………………………………………... 7
V. RECOMMENDATIONS………..………………………………………………………….... 8
VI. BIBLIOGRAPHY……………………..……………………………………………..…….… 9
I.
INTRODUCTION
a. Background of the Study
With the outbreak of insect-borne diseases such as malaria, Lyme disease, Dengue fever, bubonic
plague and West Nile fever, insect repellents were researched and developed to control and prevent such
incidences. Insect repellents are substances which discourage insects (and arthropods in general) from
landing or climbing on applied surfaces. DEET (or N,N-Diethyl-meta-toluamide) is the most common
active ingredient in insect repellents (Syed and Leal, 2008). Intended to be applied to skin or to clothing,
it is primarily used to repel mosquitoes. However, recent studies have been conducted showing that
DEET products are not likely to be used under clothing or on damaged skin as they act as skin irritants. It
even has been found to inhibit the activity of a central nervous system enzyme, acetylcholinesterase, in
both insects and mammals (Corbel et al., 2009). And not to mention, it further poses environmental risks
due to its toxic nature especially to some aquatic species (U.S. Environmental Protection Agency, 1980).
And so alternatives, commonly essential oils from plants, are being developed and used. This study aims
to assess the feasibility of an insect repellent candle from Tanglad leaf extract in paraffin wax.
b. Statement of the Problem
The worldwide threat of arthropod transmitted diseases, with their associated morbidity and
mortality, underscores the need for effective insect repellents. The researcher sought to determine the
feasibility of an insect repellent candle (paraffin) from Tanglad leaf extract.
c. Significance of the Study
This study is significant in a way that it seeks to significantly reduce insect-borne diseases,
develop a much more economically cheaper and environmentally safer alternative; that is: an insect
repellent candle (paraffin) from Tanglad leaf extract.
d. Objectives
The objectives of this study are: (1) to obtain leaf extract from Tanglad using denatured alcohol,
(2) to mold a candle with the extract; and (3) to test the insect repellent property of the candle.
e. Scope and Limitations
This study is limited only to the feasibility of creating an insect repellent candle from Tanglad
leaf extract in paraffin wax.
f.
Definition of Terms
Insect repellent - substance applied to skin, clothing, or other surfaces which discourages insects
(and arthropods in general) from landing or climbing on protected surfaces.
Paraffin - is mostly found as a white, odorless, tasteless, waxy solid, with a typical melting point
between about 46 and 68 °C (115 and 154 °F); mainly used in candle-making.
Tanglad (lemongrass) - genus Cymbopogon, about 55 species of grasses, (of which the type
species is Cymbopogon citratus) native to warm temperate and tropical regions of the Old World and
Oceania.
Citronella oil - is one of the essential oils obtained from the leaves and stems of different species
of Cymbopogon; also a renowned plant-based insect repellent, and has been registered for this use in the
United States since 1948.
DEET - N,N-Diethyl-meta-toluamide, is a slightly yellow oil. It is the most common active
ingredient in insect repellents. Its use is now usually discouraged due to its toxicity and other precautions.
Aedes aegypti - is a mosquito that can spread the dengue fever, Chikungunya and yellow fever
viruses, and other diseases. The mosquito can be recognized by white markings on legs and a marking in
the form of a lyre on the thorax.
g. Review of Related Literature
Multiple species of insect pests, including mosquitoes, ticks, flies, midges, chiggers, and fleas,
feed on people and transmit more than 100 bacterial, protozoan, parasitic, and rickettsial diseases to
humans. A single bite from an infectious vector is even known to be sufficient to transmit disease
(Roberts et al., 2008).
Mosquitoes, a common insect in the family Culicidae, are a vector agent that carries diseasecausing viruses and parasites from person to person without catching the disease themselves (Harbach,
2008). There are about 3,500 species of mosquitoes found throughout the world. In some species, the
females feed on humans, and are therefore vectors for a number of infectious diseases affecting millions
of people per year. The principal mosquito borne diseases are the viral diseases yellow fever, dengue
fever and Chikungunya, transmitted mostly by the Aedes aegypti, and malaria carried by the genus
Anopheles (The American Mosquito Control Association, 2008). Malaria, which is transmitted by the bite
of a mosquito infected with the single-cell protozoan Plasmodium, is responsible for 3,000,000 deaths
annually. Mosquitoes are estimated to transmit disease to more than 700 million people annually in
Africa, South America, Central America, Mexico and much of Asia with millions of resulting deaths. At
least 2 million people annually die of these diseases (Molavi, 2003).
There are many methods used for mosquito control and one of them is through the use of insect
repellents. Efforts of finding a desirable repellent have been hampered by the numerous variables that
affect the inherent repellency of any chemical. Repellents do not all share a single mode of action, and
surprisingly little is known about how repellents act on their target insects (Davis, 1985).
DEET remains to be the most common active ingredient in insect repellents worldwide. However,
because of its toxic property which poses health and environmental risks, efforts have been done on
developing better alternatives.
For 60 years, citronella oil has been used as an insect repellent and as a biopesticide with a nontoxic mode of action (U.S. Environmental Protection Agency, 1999). Its mosquito repellent qualities have
been verified by research, including effectiveness in repelling Aedes aegypti (yellow fever mosquito)
(Matsuda et al., 1996). While most essential oil based repellents are not as effective as DEET, research
shows that citronella oil can be comparable, and somewhat better specifically as mosquito repellent
(Fradin and Day, 2002).
Citronella oil is obtained from the leaves and stems of different species of Cymbopogon (Lawless,
1995).
Cymbopogon citratus, commonly known as lemon grass or Tanglad, is a tropical plant
from Southeast Asia and is very well abundant in the Philippines (Leite et al., 1986). Alternative
Indigenous Development Foundation Inc. (Adfi), an NGO, even established Tanglad essential
oil production via distillery plants in Mambugsay, South of Negros and Escalante, Negros Occidental.
(Clemente, 2008).
This study therefore assesses the feasibility of creating an insect repellent candle from Tanglad
leaf extract in paraffin wax.
II.
METHODOLOGY
a. Materials
250 g of fresh Tanglad leaves
500 mL of denatured alcohol
1 kilo of paraffin wax gratings
Candle molders
Candle wick / threads
Water basins
b. Flow Chart
Obtain 250 g of Tanglad
leaves.
Cut into fine pieces.
Soak in 500mL
denatured alcohol.
Obtain a kilo of paraffin
gratings.
Prepare candle-making
set-up.
Cover and set-aside for
2 nights.
Melt gratings by
heating.
Filter kept leaf extract
through a cheesecloth.
Mix 200mL filtrate into
the melted wax.
Remove candle from
the molder.
Let it cool down.
Place the mixture in the
prepared molders.
c. General Procedure
Two hundred fifty (250) g of fresh cultivated Tanglad leaves were obtained. They were cut into
fine pieces and were soaked in 500 mL denatured alcohol. They were then covered and were left
overnight for 2 days.
To prepare for the candle-making procedure, a kilo of paraffin wax gratings was obtained and
was melted down by heating. The kept leaf extract in denatured alcohol was then filtered through a fine
cheesecloth and 200 mL of the filtrate were added into the melted wax. It was then transferred to prepared
candle molders with fixed candle wicks and they were left to cool down. Once solidified, the candles
were removed from the molders and were subjected to test for insect repellent properties.
To test for the insect repellent property of the candles, outdoor place with notable mosquito
presence is used. A healthy human bait is introduced during the night (8pm). The subject wore clothing
that permitted exposure of legs from knee to ankle. The subject had clean bare legs free of insect
repellant, lotion, or other scent sources. For the control set-up, 2 lighted ordinary candles were placed
near the mosquito dwellings for 2 hours. The number of mosquito landed on the skin was then observed
and noted. For the experimental set-up, the prepared insect repellent candle was next introduced in the
same manner of procedure as the former.
III.
RESULTS (FINDINGS)
Ordinary Candle
Tanglad Candle
22
4
Number of mosquitoes landed
on skin during the 2-hr test
During the test, temperatures ranged from 22.5° to 27° C. Wind speed was less than 5 km/h
during all nights. No rain fell during the evaluations. The subject significantly received fewer mosquito
landings with Tanglad candles than with the ordinary one.
IV.
DISCUSSION (ANALYSIS OF DATA)
Essential oils like citronella oil are concentrated, hydrophobic liquid containing volatile aroma
compounds. They can be extracted through solvent extraction (Schnaubelt, 1999). This is done through
the use of a solvent, often ethyl alcohol, which dissolves volatile low-molecular weight compounds and
so extracts essential oils. This study used denatured alcohol, a typical grade of ethyl alcohol, as solvent to
extract citronella oil (The Online Distillery Network, 1993).
Candles which are technically solid blocks of fuel with an embedded wick are commonly made
from paraffin wax (Hamins et al., 2005). Prior to pouring of the melted wax, fragrance oils are often
added to provide natural scents. This study introduced instead citronella oil dissolved in denatured alcohol
into melted wax.
The usual habitat for mosquitoes is in water which includes salt-marshes, lakes, puddles, natural
reservoirs on a plant, and artificial water containers such as a plastic buckets (Westchester County
Department of Health, 2010). Such set-up has been the subject in this study for the purpose of testing. For
the controlled set-up, it has been observed that the introduction of an ordinary candle did not significantly
repel mosquitoes. While in the Tanglad candle set-up, mosquitoes were notably repelled. This observation
therefore provides confirmation for the repellent activity of the candle made with Tanglad essential oil
extract.
V.
CONCLUSION
This study concludes that the use of insect repellent candles from Tanglad leaf extract in paraffin
wax is an effective cost-efficient way of repelling household insect pests.
VI.
RECOMMENDATIONS
The researcher further recommends the determination of the optimal effective proportions of the
Tanglad leaves, denatured alcohol and paraffin wax used. Extensive test analysis of the insect repellent
candle to other known household insect pests and effective range are also suggested.
VII.
BIBLIOGRAPHY
Corbel V., Stankiewicz M, Pennetier C., Fournier D., Stojan J., Girard E., Dimitrov M. and Molgó J.
2009. "Evidence for inhibition of cholinesterases in insect and mammalian nervous systems by
the insect repellent deet". BMC Biology 7:47 7: 47.
Davis E. 1985. Insect repellents: concepts of their mode of action relative to potential sensory
mechanisms in mosquitoes (Diptera: Culicidae). J Med Entomol. 22:237-43.
Fradin M. and Day J. 2002. "Comparative Efficacy of Insect Repellents against Mosquito Bites". N Engl
J Med 347 (1): 13–18.
Hamins A., B undy M. and Dillon S. 2005. "Characterization of Candle Flames." Journal of Fire
Protection Engineering, Vol. 15.
Harbach R. 2008. "Family Culicidae Meigen, 1818". Mosquito Taxonomic Inventory.
Lawless, J. 1995. The Illustrated Encyclopedia of Essential Oils.
Leite J., Seabra M. and Maluf E. 1986. "Pharmacology of lemongrass (Cymbopogon citratus Stapf). III.
Assessment of eventual toxic, hypnotic and anxiolytic effects on humans". J
Ethnopharmacol 17 (1): 75–83.
Martinez-Clemente J. 2008. Tanglad goes mainstream, yields essential oils. Inquirer.net.
Matsuda B., Surgeoner G., Heal J., Tucker A. and Maciarello M. 1996. "Essential oil analysis and field
evaluation of the citrosa plant "Pelargonium citrosum" as a repellent against populations of Aedes
mosquitoes". Journal of the American Mosquito Control Association 12 (1): 69–74.
Molavi A. 2003. "Africa's Malaria Death Toll Still "Outrageously High"". National Geographic.
Roberts L., John J. and Gerald D. 2008. Foundations of Parasitology. McGraw Hill.
Schnaubelt K. 1999. Advanced Aromatherapy: The Science of Essential Oil Therapy. Healing Arts Press.
Syed Z and Leal WS. 2008. "Mosquitoes smell and avoid the insect repellent DEET". Proc. Natl. Acad.
Sci. USA 105 (36): 13598.
U.S. Environmental Protection Agency. 1980. Office of Pesticides and Toxic Substances. N,N-diethyl-mtoluamide (Deet) Pesticide Registration Standard. December, 1980. 83 pp.
"Citronella (Oil of Citronella) (021901) Fact Sheet." 1999. U.S. Environmental Protection Agency.
"Ethanol Denaturants". 1993. The Online Distillery Network.
"Mosquito-Borne Diseases". 2008. The American Mosquito Control Association.
"Mosquito's Life Cycle". Westchester County Department of Health. Retrieved April 10, 2010.