Pesticides are applied intentionally to the environment by people for the purpose of improving environmental quality for humans, domesticated animals, and plants. Despite the fears and real problems they create, pesticides are partly responsible for the physical well-being enjoyed by most people all over the world.
In particular, pesticides are credited for making an important contribution to making food production more efficient. For example, in 1850 each U.S. farmer produced enough food and fiber for himself and three other people. By the year 2000, each farmer was producing enough food and fiber for more than 135 people, thanks in large part to pesticides. Nonetheless, all is not good with pesticides today.
Concerns about the environment:
First, as pesticides continue to become more prevalent in society, and we become more dependent on them, there are rising concerns about their impacts to the environment.
Second, the quality of our environment is a major issue today, and with that there is increasing urgency to protect the nation’s air, soil, water, beneficial insects, and wildlife, including endangered species.
Third, some pesticides can be persistent within the environment where they can become biologically concentrated. When this happens, the pesticide can become more concentrated in organisms higher up the food chain and cause serious problems. For example, DDT (Dichloro Diphenyl Trichloroethane) is an insecticide with low mammalian toxicity and regarded as safe to use. DDT was widely used insecticide until 1972 when it was banned by the US Environmental Protection Agency (EPA) because it formed biological concentrations in species higher up in the food chain, like the bald eagle.
What is Limonene?
Limonene is a colorless liquid aliphatic hydrocarbon classified as cyclic monoterpene and is a major component in the oil of citrus fruit peels, known for its pleasant citrus aroma. Commercially, it is derived from orange oil—a byproduct of citrus juice processing—making it both renewable and economically feasible. It exists primarily in the d-limonene isomeric form, which is prized for its solvent properties, volatility, and compatibility with many organic compounds.
- Limonene has two forms it occurs naturally (isomers): d-limonene and l-limonene.
- D-limonene:
- The principal component of the essential oils present in the rind of citrus fruits, such as orange, lemon, mandarin, grapefruit, and lime.
- A colorless oil that is sparingly soluble in water, has a sweet orange smell, and is widely used in the cosmetics industry.
- Commercially, it is mostly obtained from waste orange peels.
- D-limonene:
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- L-limonene:
- Least abundant of the essential oils present in the rind of citrus fruits.
- Has a turpentine smell.
- Also found in plants as the major component of volatiles emitted by oaks and pines.
- L-limonene:
Limonene as an adjuvant to weed control
- Solvent and Carrier:
- Limonene’s lipophilic nature makes it an excellent solvent for many active ingredients. It enhances solubility and aids in the uniform dispersion of agrochemicals, particularly oils and hydrophobic compounds
- Penetration Enhancer:
- Limonene acts as a cuticular penetration enhancer, enabling better delivery of active ingredients into plant tissues. This is critical in foliar applications where translocation is needed.
- Low Environmental Impact:
- Unlike petroleum-based solvents, limonene is biodegradable, non-persistent, and exhibits low ecotoxicity. It degrades rapidly in soil and water, reducing the risk of bioaccumulation or non-target effects.
- Generally Recognized As Safe (GRAS) and Low Mammalian Toxicity:
- Limonene is classified as GRAS (Generally Recognized as Safe) by the U.S. FDA and is commonly used in food and cosmetics. This translates into a low human and animal health risk profile, which is especially important for applicator safety and residue concerns in food crops.
- Renewable Origin:
- Its derivation from citrus waste aligns limonene with the principles of circular bioeconomy, utilizing agricultural byproducts instead of petrochemical feedstocks.
Limonene can be used as an adjuvant. For example Brewer International’s Cide-Kick™ and Cide-Kick II™ both of which are formulated with limonene.
Cide-Kick™ and Cide-Kick II™:
- Formulated with limonene.
- Nonionic surfactants.
- Act as a combined wetting agent, activator, and penetrant.
- Helps herbicide uptake by breaking down the waxy cuticles on leaf surfaces and penetration of the bud and bark area.
- Compatible with most aquatic and terrestrial herbicides, insecticides, and other pesticides.
- Labeled uses include:
- In low volume basal applications in brush control.
- In the agriculture, citrus, and turf industries for weed control or invasive plant species control.
- In forest site preparation.
- In utility rights-of-way and roadside vegetation management.
- In aquatic systems for control of surface and submerged plants.
- To achieve the best control of invasive plants when using Cide Kick™, make sure you read the herbicide label and follow all recommendations.
- Insecticidal properties – When Cide Kick™ was applied alone on collards and tomato, a high level of control of silverleaf whitefly (74%) was reported.
The future for Limonene
As the demand for limonene-based products continues to increase, wider application in agriculture, aquatic and terrestrial vegetation, and management of invasive species in rights of way and forestry is anticipated. Why? Because limonene is safe for humans, the environment, and wildlife.
References
- Ciriminna R., M. Lomeli-Rodriguez, P.D. Carà, J.A. Lopez-Sanchez, M. Pagliaro. 2014. Limonene: a versatile chemical of the bioeconomy. Chemical Comm. https://pubs.rsc.org/en/content/articlelanding/2014/cc/c4cc06147k
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Our products are used widely across the United States in agriculture, aquatics, forestry, rights of way, and land management.
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