Essential oils are currently available for beauty purposes and household products. Orange, limon and other oil are not pressed off from the fruit juice. They are industrially extracted from the inner rids of peels by methods of cold pressing and steam distillation. Cold pressing of fruit peels is used to obtain food grade. It means that oil can be eaten by humans. Steam distillation is applied to get technical grade. It can be mixed with water to obtain insecticide products, which consist of orange terpenes for termite treatment.
In fact, orange oil does not exterminate pests itself, it contains a special active ingredient. Some specialists claim that termites and other insects die from the citric acid. That is not really true. The content of this acid is too low (0.1%) in essential oil and not enough to kill termites.
Two types of orange terpenes for termite treatment
The key ingredient of essential oils obtained from the peels of oranges, limes, limons and other citrus is d-limonene. It is one of natural terpenes or terpenoids. It is an oil nutrient toxic to drywood and subterranean termites. Its solvent activity causes melting chitinaceous exoskeleton of termites via fumigant action and on direct contact.
Neroli oil, steam distilled from bitter orange flowers, clove orange and limon blossom (neroli oil), contains an orange terpene known as cis-nerol. It produces the same solvent activity against termites as d-limonene’s. USDA researchers studied toxic effects of orange terpenes for termites treatment and came to conclusion that cis-nerol induced morphological changes to exoskeleton of Formosan subterraneans (Rhinotermitidae).
When orange and neroli oil fumigation is performed, d-limonene and cis-nerol dissolve the wax coat of a termite’s respiratory system and damages insect’s cell membranes and cuticular wax layer. When neroli oil spot injections are applied, cis-nerol destroys the wood pest exoskeleton on contact and via mutual feeding process.
Are d-Limonene and cis-nerol toxic to humans and nature?
D-limonene and cis-nerol are the most common terpenes in nature. They are registered in the Code of Federal Regulations as safe (GRAS) and non-toxic to mammals and environment. They do not leave residuals after eradication. They were tested for carcinogenicity on white rats and mice. Orange terpenes are not considered to be toxic, carcirogenic and mutagenic. They do not lead to health hazard to humans and pets. It is also granted by EPA as eco-friendly termicide ingredients.
Are orange terpenes allergic to mammals?
According to GRAS d-Limonene and cis-nerol do not produce the carcirogen and toxic risk to humans and their pets if used as directed. Pet shampoos, perfumes and household cleaners contain orange oil. Though, orange terpenes are potentially allergic as other substances and products are. They are likely to cause skin and stomach reactions. To compare with other chemicals used for insect extermination, limonene and nerol are less allergic. To avoid eyes and skin irritation and vomiting, be aware of self-precautions: do not inhale and eat pure essential oil; put on personal protective equipment (gloves, goggles, long sleeves) during working with orange terpenes for termite treatment.