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Deleterious Effects of Roundup

nature image by Andrea Slaviček from

Roundup is an herbicide produced by the Monsanto corporation. Its active ingredient is glyphosate, an organic phosphate, combined with other ingredients including a surfactant called polyethoxylated tallowamine that helps the product penetrate plant surfaces. Glyphosate has been used as an herbicide since the 1970s and is hailed as non-toxic and environmentally safe. But recent studies show glyphosate herbicides and Roundup in particular are more dangerous for people, animals, and the environment than previously believed.

Direct Contact

According to the manufacturer's labeling, Roundup should not be inhaled or come into contact with skin and eyes. Inhalation can result in coughing, nausea, headaches and difficulty breathing. Skin contact can result in a burning rash, numbness, swelling or eczema. Roundup can cause severe eye irritation or burns. Clothing that has soaked Roundup in should be thrown away because it can't be completely washed out of it. Pets and livestock can become sick or die from eating plants that have recently been sprayed with Roundup.

Indirect Contact

When Roundup is sprayed, it can travel up to 1,300 feet in the wind, so wild plants and trees near spraying areas can be damaged or destroyed. In Australia, the use of glyphosate has been banned near waterways, and Denmark has banned glyphosate altogether because contamination from the herbicide has been found in the drinking water supply. The province of Ontario banned all glyphosate herbicides for cosmetic and domestic use in 2009. Roundup kills amphibians and causes genetic deformities in frogs, and can hurt wildlife populations by destroying their shelter and food supply. A 2001, Swedish study found that agricultural workers exposed to glyphosate were three times as likely to contract non-Hodgkin's lymphoma.

Effects on Soil

Roundup can leach from plant roots into the soil, changing its composition. Parasites that cause root rot increase, as well as a fungus that causes sudden death in the plants. Glyphosate has a half-life of up to 140 days in the soil, and plants like lettuce and carrots grown in soil sprayed with Roundup the previous year can contain traces of the product. Roundup also kills crucial beneficial soil microbes like mycorrhizal fungi, which help plant roots retain moisture and take up nutrients, and rhizobium bacteria, which fix nitrogen in the soil.

Effects on Reproduction

In 1995, scientists discovered exposure to low doses of glyphosate significantly decreased male fertility in rabbits by reducing sperm count and damaging sperm cells. A 2005 study showed that exposing human placental and embryonic cells to extremely low doses of Roundup resulted in damage or death to the cells. Among agricultural workers routinely exposed to Roundup, there is a high incidence of infertility, miscarriage, and low birth weight.

Effects on Global Food Supply

Since Roundup kills desirable plants as well as weeds, Monsanto patented genetically modified (GM) strains of soybeans, corn and sugar beets that are now grown throughout the world. These “Roundup ready” strains don't die when Roundup is applied to them, so farmers might use more of the product than necessary, which increases food, soil, and water contamination. GM food is linked to increased food allergies in people and decreased fertility in mice, pigs and cows. Cross-pollination between Roundup ready and non-GM crops is unavoidable, but the effect of GM crops on non-GM crops and wild plants is not yet clear. In order to ensure that farmers worldwide continue buying Monsanto's patented seed year after year, further genetic modification causes the plants to produce sterile seeds. This prevents farmers from saving seeds to use in subsequent years, which creates financial strain and decreased food production, particularly in developing countries. The Action Group on Erosion, Technology, and Concentration reports that 1.4 billion people rely on farm-saved seeds.

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