1.1 Introduction
Mosquito repellents are substances that are designed to make surfaces unpleasant or unattractive to mosquitoes. They typically contain an active ingredient that repels mosquitoes as well as secondary ingredients, which aid in delivery and cosmetic appeal. They are available in many forms, from creams to lotions to oils, but are most often sold as aerosol products. Traditionally, various types of substances have been used to repel mosquitoes. These include such things as smoke, plant extracts, oils, tars, and muds. As insect repellent technology became more sophisticated, individual compounds were discovered and isolated. This allowed the formulation of new, more efficient forms of mosquito repellents.
As a prelude to other parts of this study, this chapter will discuss the background upon which this study was initiated, the statement of problems that led to this study, the Aim and Objectives of the study. Others are Significance of the study, Scope of work, Research hypothesis and questions, Limitations of the Study and Definition of technical terms.
1.2 Background of Study
The first truly effective active ingredient used in mosquito repellents was citronella oil. This material is an herbal extract derived from the citronella plant, an Asian grass. While citronella had been used for centuries for medicinal purposes, its repellence was only accidentally discovered in 1901, when it was used as a hairdressing fragrance. Since citronella oil is a fragrant material, it is thought that the chemical terpenes of which it is composed are responsible for its repellent activity. Citronella oil does repel mosquitoes, but it has certain characteristics which limit its effectiveness. For example, it is very volatile and evaporates too quickly from surfaces to which it is applied. Also, large amounts are needed to be effective.
The disadvantages of using citronella oil prompted researchers to study alternative synthetic compounds. Many of the early attempts at creating synthetic insect repellents were initiated by the United States military. Out of this research came the discovery of the repellent dimethyl phthalate in 1929. This material showed a good level of effectiveness against certain insect species, but it was ineffective against others. Two other materials were developed as insect repellents. Indalone was found to repel insects in 1937, and Rutgers 612 (2-ethyl-1,3-hexane diol) was synthesized soon after. Like dimethyl phthalate, these materials had certain limitations which prevented their widespread use.
Since none of the available materials were ideal repellents, research into new synthetic materials continued. In 1955, scientists synthesized DEET (n-n-diethylnetatoluamide), currently the most widely used active ingredient for mosquito repellents. After its discovery, repellent manufacturers developed many different forms in which to deliver DEET, such as creams, lotions, and aerosols.
Most repellent chemicals work by interfering with the mosquito's homing system. This homing system, located on the antennae, is made up of a number of chemical receptors. Research has shown that these chemical receptors are activated by lactic acid, which naturally evaporates from the skin of warm-blooded animals. The mosquitoes have the innate ability to follow the lactic acid emissions to their source. However, when a repellent ingredient such as DEET is applied to the skin, it also evaporates. It is thought that the chemical inhibits the binding of the lactic acid to the mosquito's chemical receptors. This essentially hides the protected person from the mosquito. Since the active ingredient must evaporate from the surface to work, the repellent activity lasts for a limited time.
Therefore, in Nigeria where the research was carried out, the activities that was conducted is to know the Production of Mosquitoes Repellent Insecticide.
1.3 Statement of Problems
Investigation revealed that there is over the years, mosquitoes pose a great threat to humans' health which triggered the development of a lasting solution to the invasion of mosquitoes in our environment. Different methods had been detected to control mosquitoes but there is need to develop a cheap, easy to produce, and long lasting solution.
1.4 Aim and Objectives of Study
The aim of the study is to determine the Production process of Mosquitoes Repellent Insecticide. In achieving this aim, the following specific objectives were laid out as follows:
- To examine the mosquito repellant insecticides a lasting solution to mosquito invasion;
- To investigate the effect of plants extract on mosquito; and
- To produce mosquitoes repellent using plant extracts which will be cheap, effective and readily available for everyone even in rural area.
1.5 Research Questions
The study came up with research questions so as to be able to ascertain the above stated objectives. The specific research questions for the study are stated below as follows:
- What is an insecticide?
- What is the effect of plants extract on mosquito?
- Are mosquito repellant insecticides a lasting solution to mosquito invasion?
- How can mosquito repellant be produced using plant extracts which will be cheap, effective and readily available for everyone even in rural area?
1.6 Significance of Study
The relevance of the study entails that mosquitoes can be reduced or controlled around our homes naturally through the use of natural or biological means. Predatory fish (Gambusia), Dragonflies, plant repellant, bacteria and even other mosquitoes that are mosquito eaters. Citrosa, Lemon thyme, and Rosemary plants are known to be good insect repellant. Bacillus Thurigiesis Israelensis is a Natural occurring bacteria used as a larvacide in ponds and other areas where mosquitoes are breeding. These are poisonous to mosquito larvae when they feed on it in the water.
Mosquito trap are also good method of controlling mosquitoes on our area.Orange peel also known as Cestrum is a wonderful hybrid derived from Cestrum diurnum and Cestrum Nocturnum. Cestrum is a veritable living bouquet of pure orange blossoms that strives well in warm climates. Orange peel is a fragrant orange flower, it need low maintenance and strives in hot weather. Orange peel contains oil known as Limonene oil which has a lethal effect on mosquito and some other insects. Hence, Cestrum can be used as an active ingredient to produce mosquito coil, which when ignited will repel mosquitoes within the limit of the smoke.
This study will be of immense benefit to other researchers who intend to know more on this study and can also be used by non-researchers to build more on their research work. This study contributes to knowledge and could serve as a guide for other study.
1.8 Scope of Study
The scope of the research is focused on the production of mosquito repellant insecticides using plant extracts.
1.9 Limitations of the Study
During the course of this study, many things militated against its completion, some of which are:
- Time Constraint: The time frame given to accomplish this project was very short due to school academic calendar and it was carried out under pressure which made the researcher not to implement some necessary features.
- Research material: availability of research material is a major setback to the scope of the study.
- Frequent power failure: This made the researcher append more money on fuel to ensure sustainable power.
- Financial Constraint: Insufficient fund tends to impede the efficiency of the researcher in sourcing for the relevant materials, literature or information and in the process of data collection (internet).
