Plant Based Repellents - Green Mosquito Control

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A variety of essential oils have significant repellent effects. However, the effects tend

to dissipate quickly due to their high volatility. Essential oils generally act in the vapor

phase being active only for a short period. For example, citronella oil is highly volatile,

and thus, mosquito repellents with citronella oil as the major component need to be reap-

plied every 20 - 60 minutes. The drawback of the short protection time could be improved

via formulation technology development, by retaining the active components on the skin

for longer periods. Cream-based formulations and polymer mixture-based formulations led

to an increase in the repellent effect [42].

Currently, nanotechnology is extensively used to prepare repellents with essential oils

for better efficiency. Nanoparticle fabrication by using plant components as reducing

and stabilizing agents has several advantages compared with conventional methods. The

size, shape and efficiency of nanoparticles against mosquitos vary depending on the plant

sources. For example silver nanoparticles containing neem are mostly spherical, whereas

silver nanoparticles fabricated using leaves from bush plum are cubical [43, 44]. In addi-

tion, the use of nanotechnology for essential oil delivery could reduce the costs, steps for

development process an risks associated with pressure, temperature and energy.

11.5

CONCLUSION

Repellency is an important way of preventing vector-borne diseases by reducing man

- mosquito contact. Because of the possible negative impact on human health and environ-

ment, the synthetic repellents are gradually being replaced by plant-based repellents. Many

studies show that different plant essential oils can be effectively used as “green” repellents

for mosquito control. Considering that essential oils are highly volatile, evaporate quickly

and leave the user unprotected, the biggest challenge in applying essential oil-derived re-

pellents is to increase their effectiveness and extending their longevity. For this purpose,

various techniques and methods are being developed and applied.

ACKNOWLEDGMENTS

This chapter is partly based on work performed within the framework of IMAAC

(https://imaac.eu/) related to COST Action CA16227 (Investigation & Mathe-

matical Analysis of Avant-garde Disease Control via Mosquito Nano-Tech-Repellents,

https://cost.eu/actions/CA16227/), supported by COST Association (Euro-

pean Cooperation in Science and Technology).