Man dying of cancer takes the stand against Monsanto

SAN FRANCISCO (KGO) -- It is the first time St, Louis-based Monsanto Company has had to defend one of its products, Roundup in front a jury. Roundup is a popular weed killer.

The man suing the agrochemical company is Dewayne Johnson of Vallejo. He took the stand today in the trial which began on July and is meant to be the bellwether of thousands of similar cases.

The case is being tried in a San Francisco Superior Court. The 46-year-old plaintiff is a former groundskeeper for the Benicia Unified School District.

The suit says Johnson was exposed to large amounts of Roundup for two years. At one point, Johnson says his entire body was soaked with the chemical when a hose broke.

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Morning a dermatologist testified that he first examined Johnson for a rash on his body in February 2014. Dr. Ope Ofodile told the jury that Johnson was not responding to treatment and that the lesions on his body began to spread very aggressively. "He had new lesions and was headed in the wrong direction," said Dr. Ofodile.

Johnson was later diagnosed with non-Hodgkin's lymphoma.

In court it was revealed that Johnson had previously contacted Monsanto but the company never responded. Instead, Johnson continued using Roundup. His attorney claims that Monsanto knew about the risk and failed to warn people.

"If they just would have called him back, he would have stopped spraying, but his cancer got worse and worse and worse and during that time he was spraying," said Brent Wisner, Johnson's attorney.

Johnson's wife, Araceli took the stand before him saying that once he was diagnosed with cancer, he could not sleep, was in pain, depressed and at times would cried.

Johnson who has undergone several rounds of chemotherapy, talked about his two sons and wife and how life had dramatically changed after the diagnosis.

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Monsanto has said "The scientific evidence is overwhelming that glyphosate-based products do not cause cancer and did not cause Mr. Johnson's cancer. "

But in 2015, an agency associated with the World Health Organization classified it as a "probable human carcinogen."

Environmental attorney and advocate Robert F. Kennedy Jr. is attending this trial. The son of the late "Bobby" Kennedy is part of a legal team with cases pending against Monsanto.

Johnson is suing for unspecified punitive damages and will continue to testify this afternoon.