Documents Expose Corporate Cover-up: The Link Between Paraquat and Parkinson’s Disease

For years, the company Syngenta has adamantly denied any link between its widely used weed-killing chemical, paraquat, and Parkinson’s disease, but a recent investigation has uncovered a different reality. We explore the revelations from a cache of internal documents, obtained by The New Lede in collaboration with the Guardian, that shed light on Syngenta’s questionable practices. Brace yourself for the shocking truth about this corporate giant and the implications it has for public health.

The Paraquat-Parkinson’s Debate

For years, Syngenta has been manufacturing and marketing paraquat, one of the most commonly used weed-killing chemicals worldwide. However, concerns about its potential connection to Parkinson’s disease have plagued the company. Syngenta has consistently refuted any scientific evidence linking paraquat to the disease, claiming that it does not readily affect brain cells or cross the blood-brain barrier.

The Internal Corporate Documents

The documents uncovered reveal a different story. These records, dating back to the 1950s, show that Syngenta has at times contradicted its own public narrative. While the documents don’t explicitly state that the company believed paraquat causes Parkinson’s, they do expose corporate strategies aimed at protecting product sales, discrediting external research, and influencing regulators.

Manipulating Advisory Panels and Experts

One disturbing tactic detailed in the documents was Syngenta’s covert effort to influence the US Environmental Protection Agency (EPA) and prevent respected scientists, such as Dr. Deborah Cory-Slechta, from sitting on advisory panels. Driven by concerns that her work provided strong evidence linking paraquat to Parkinson’s, Syngenta aimed to discredit her research through industry lobbyists.

Withholding Adverse Research Findings

The documents also reveal that Syngenta withheld its own research showing adverse effects of paraquat on brain tissue from regulators. Instead, they downplayed similar findings reported by independent scientists. This behavior raises ethical concerns about corporate transparency and public health.

Corporate Playbook for Downplaying Dangers

The evidence points to a corporate playbook used by Syngenta to downplay potential dangers associated with its profitable product, paraquat. While independent researchers continued to find links between paraquat and Parkinson’s, the company developed an “influencing” strategy to safeguard sales and registrations, involving academia, regulators, and NGOs.

Paraquat: A Unique Herbicide

Paraquat is touted as a “unique herbicide” by Syngenta, offering safe and effective weed control. However, its use has grown exponentially over the years, coinciding with the alarming rise in Parkinson’s cases globally.

The Human Impact

Thousands of people have filed lawsuits against Syngenta and Chevron USA, alleging that they developed Parkinson’s due to long-term exposure to paraquat. These documents reveal a history of corporate negligence, prioritizing profit over public health. The prevalence of Parkinson’s has skyrocketed, and regulators must take this potential link seriously.

The Path Forward

Syngenta’s recent $187.5 million settlement to resolve Parkinson’s-related lawsuits is an acknowledgment of the seriousness of the issue. As the EPA revisits its assessment of paraquat, it is crucial for them to consider the wealth of evidence connecting the chemical to Parkinson’s disease.


The revelations from the internal corporate documents are not only a wake-up call for Syngenta but for the entire industry. As consumers, it is our responsibility to demand transparency, accountability, and ethical practices from companies that provide products essential to our daily lives. Only by holding them accountable can we ensure a safer and healthier future for all. Remember, public health should never be compromised for profit. It’s time for us to stand together and demand better. If you or a loved one have been affected by corporate negligence and greed, contact OnderLaw today for your free, no-obligation consultation.