The Chemistry of RoundUp


Roundup is a herbicide manufactured by Monsanto Company which is designed to kill every plant except those that are bred to be resistant to it. I chose to do my research on Roundup because it is a product that we use every year on our farm but I had a very limited knowledge on how it works. My life is affected greatly by this because after the introduction of Roundup into commercial use, I got to quit walking soybean fields to pull weeds by hand. Roundup helped us control weeds much easier and also more effectively.


Roundup is comprised of very few ingredients. The main one that it is most commonly associated with is Glyphosate, a potassium salt known for its effectivity in killing weeds. The second ingredient is 1-4 Dioxane (C4H8O2), a stabilizer for the Glyphosate to ensure that it stays usable. The next ingredient in Roundup is a surfactant. Surfactants are one of the main ingredients in soap that work to increase the surface area of a product to give it a stronger mode of action. The fourth and final ingredient is water (H2O), which is used strictly as a carrier for the Glyphosate.

Main Chemicals, Compounds, or Components:

The only active ingredient in Roundup is the chemical Glyphosate (C3H8NO5P). It is considered a potassium salt because it dissolves easily in water. Glyphosate is a weak acid which will dissociate when added into water to which helps it become very reactive. It is used as the only weed killer from the combination of these four main ingredients.

Surfactants are another main ingredient in Roundup. The purpose of a surfactant is to make the dissociated Glyphosate react with more plants and also react better with the plants that it comes into contact with. Surfactants are primarily used as an ingredient in most soaps making them very basic. An interesting fact about Roundup is that it was originally made to be a dish soap, so it was originally meant to be a surfactant.

Chemistry’s Role:

When Roundup is first sprayed on the plant, it is absorbed through the leaves and transported throughout the entire plant. The surfactant in the glyphosate comes into play here as it helps the glyphosate get into the plant easier. The Glyphosate then reacts inside the plant to prevent the activities of the enzymes from producing amino acids essential to plant life. The plant will eventually starve to death because it lacks all necessary nutrients to survive. The plant begins to deteriorate and eventually dies in about the time of one week.

Background Research:

The process for making Glyphosate is very involved. To begin, they start with natural gas and hydrogen cyanide, both naturally occurring. The Hydrogen cyanide is synthesized with the natural gas and ammonia. This is then reacted with formaldehyde to receive the product cyanohydrin. This product is then reacted with ammonia to reach Iminodiacetonitrile (IDAN). This is then hydrolyzed in an aqueous sodium hydroxide to get disodium iminodiacetic acid. Next, it is reacted again in an aqueous solution of formaldehyde. Finally, this resulting product is oxidized to receive glyphosate.


"Glyphosate." Glyphosate. PubChem, n.d. Web. 06 Apr. 2016.

The chemical formula of Glyphosate

"Controlling Weeds: Roundup." What Is Biology Good For? IUPUI Department of Biology,

n.d. Web. 6 Apr. 2016.

This was a very valuable website when learning Glyphosate works

"How Does Glyphosate Work." Glyphosate. Monsanto, n.d. Web. 6 Apr. 2016.

Monsanto’s website was very helpful telling in easy to understand terms how

glyphosate works

"How Is Glyphosate Used?" Glyphosate. Monsanto, n.d. Web. 6 Apr. 2016.

This page on Monsanto’s website shows

RoundupInfo. "5. How Does Roundup Work?" YouTube. YouTube, 07 Dec. 2010. Web. 06

Apr. 2016.

This video was helpful showing how Roundup works as a whole and it also explains

how safe it is and why it’s safe.

"Supplementary File 1. Overview of Publications." (n.d.): 1. Electronic Supplementary

Material. The Royal Society of Chemistry, 2012. Web. 7 Apr. 2016.

This website told how glyphosate is produced. It also provided diagrams of the

chemical reactions

"Glyphosate." General Fact Sheet. NCPI, n.d. Web. 07 Apr. 2016.

This provides some information on how it works and a lot about the health effects

of glyphosate on both the environment and humans.

About the Author:


Andrew Streff is a Senior at McCook Central High School. He takes an active role in his participation with the FFA and uses his passion for agriculture to drive himself towards success. He will be attending South Dakota State University next year to major in agriculture business and marketing. With this knowledge, Andrew will return home and take over owning and operating his family’s farm.  Andrew is on the A Honor Roll, is a member of National Honor Society, and has won national awards through the FFA as well as recently being elected to be the State FFA Treasurer.