Pesticides in Capsules Are Less Toxic and More Effective at Killing Pests

11:50, February 15, 2023

Scientists propose β-cyclodextrins for encapsulation

Pesticides in capsules are less toxic and more effective in killing pests. This was discovered by a group of chemists from China and Russia, including scientists from the Ural Federal University. The researchers proposed the use of β-cyclodextrins as capsule shells, which weaken the toxic effect of pesticides. Reducing toxicity in the long term will reduce the amount of pesticides not only in plants, but also in the human body. Humans can absorb them by eating plant foods and animal flesh. An article with the results of the research has been published in the journal Advanced Agrochem.

"Pesticides are used to kill pests and plant pathogens. They are also used to control various parasites, weeds, pests of grain and grain products, and wood. They are among the most toxic pollutants. They are very difficult to remove from the soil and are slow to decompose. As a result, they are absorbed into the roots of plants during germination and move up the food chain to enter the human body. Pesticides also tend to accumulate, especially in fatty tissues, which poses a serious threat to humans. In addition, in hot weather they can become gaseous and pollute the air," says Elena Kovaleva, Professor of the Department of Technology of Organic Synthesis at the Ural Fereral University.

For encapsulation, the scientists chose β-cyclodextrins, which are cheap and easy to synthesize. In addition, their outer structure absorbs water well and improves the solubility of pesticides. This increases their stability and reduces their toxicity. Such an approach contributes to a more targeted defense of plants against pests. The scientists found that for each pesticide, a specific modification of cyclodextrin should be used based on certain parameters and properties.

Encapsulated pesticides have other significant advantages over conventional pesticides.

"Encapsulated pesticides are solid substances encapsulated in capsules. They can be easily separated from the soil, are not absorbed into the soil, and are more friendly to the atmosphere. The capsule is more effective because it releases the pesticide more slowly. Many more different pathogenic bacteria are killed in the process. In hot weather, encapsulated pesticides do not evaporate and do not pollute the air," adds Elena Kovaleva.

For Russia and China, the transition to the use of pesticides in capsules is important. The Chinese, in particular, have been actively using traditional pesticides on small areas for many years. As a result, the soil has become so polluted that it is no longer suitable for growing crops. This environmental problem is much more acute in China than in Russia, says Elena Kovalyova. In our country, there are more suitable places for growing various crops, which are not yet so heavily polluted. However, in order to prevent an ecological disaster in Russia, we need to think about switching from traditional pesticides to encapsulated ones.

Pesticides remain harmful even in the shell (though to a lesser extent). Therefore, scientists plan to develop natural pesticides that are safe for humans and the environment. They will contain beneficial biologically active substances that can be used safely and effectively against weeds and various pathogenic bacteria.

The news article was translated by UrFU International Marketing Office. 
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