Roundup Weed Killer has been linked to a doubled risk of developing cancer, according to the testimony of a recent expert witness.

During a trial in April, Dr. Dennis Weisenburger testified that using Roundup for more than two days a year may double the risk of developing non-Hodgkin’s lymphoma. Weisenburger emphasized that the increased risk has more to do with the number of days the weed killer was used, not the number of years.

“It’s the intensity of exposure that’s more important than the length,” he said.

This estimate has been confirmed by other scientific authorities, including one conducted by researchers at the University of Washington who determined that Roundup’s key ingredient increased by 41 percent the cancer risk for a person exposed to the potent weed killer.

Weisenburger’s presented his testimony during a trial for a lawsuit filed by husband and wife Alva and Alberta P., both of whom were diagnosed with non-Hodgkin’s lymphoma after routinely spraying Roundup throughout their life. The herbicide glyphosate, contained in Roundup, is purported to be the culprit for the increased cancer risk. 

Non-Hodgkin’s lymphoma is a cancer affecting the lymphatic system, which includes the body’s immune system. This cancer forms from white blood cells called lymphocytes. Although tumors typically form in the lymph nodes (found in the neck, armpit, groin and other areas), the disease can spread to other parts of the lymphatic system including the lymphatic vessels, tonsils, adenoids, spleen, thymus and bone marrow. It may even spread to organs not involved in the lymph system.

According to the Mayo Clinic, symptoms of non-Hodgkin’s lymphoma include: swollen lymph nodes in the neck, armpits, or groin; abdominal pain and swelling; chest pain; coughing and trouble breathing; persistent fatigue; fever; night sweats; and unexplained weight loss.

This painful, life-threatening condition reportedly resulted in Alberta suffering brain damage and both she and her husband requiring canes to steady themselves.

Weisenburger estimated that Alberta used Roundup weed killer approximately 279 times and Al used the weed killer some 729 times over a span of 30 years. According to the couple, they did not wear protective equipment when spraying the weed killer because they thought the chemical was safe.

Testimony by Weisenburger has been echoed by other scientists in trials against Monsanto, Roundup’s manufacturer. UCLA professor Beate Ritz referenced a similar doubled risk statistic during her testimony in the same trial.

Ritz cited half a dozen peer-reviewed studies dating back as far as 1999. These studies reportedly showed the risk for non-Hodgkin’s lymphoma double following exposure to glyphosate for more than two days in a year. Ritz also noted that the studies have shown using glyphosate weed killers, such as Roundup, increase the cancer risk by 22 percent when compared to individuals who have never used the chemical.

She also voiced concerns about the misclassification of glyphosate risks by regulatory authorities, including the National Cancer Institute. She argued that the institute’s Argicultural Health Study was flawed and has been repeatedly criticized by the scientific community for concluding that glyphosate is not associated with cancer. Additionally, Ritz noted that the institute’s advisory committee – which she chaired – only met a few times before disbanding due to a lack of funding. Because of this, she said the misclassification was reportedly not resolved.

Expert testimony in Alberta and Al’s lawsuit bolsters the argument that their continued use of Roundup lead to their non-Hodgkin’s lymphoma. Plaintiffs around the country have filed lawsuits with similar allegations against Roundup manufacturer Monsanto.

If you or a loved one developed cancer after using Roundup as a farm worker or home gardener, you may have a legal claim. Legal migrant farm workers may also seek help. Learn more by filling out the form on this page for a FREE case evaluation.

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