Paraquat Lawsuit | Parkinson’s Disease

Research shows that paraquat exposure is dangerous, even at low levels. Paraquat side effects depend on the amount, route, and duration of exposure to the herbicide, and the person’s overall health. The herbicide enters the body via:

• Skin: Contact or penetration of the skin, mucous membranes, and other epithelial tissues (including mouth, nose, trachea, and conducting airways, particularly where cuts, abrasions, rashes, sores, or other tissue damage are present).
• Inhalation: Spray droplets enter the nose or mouth.
• Ingestion: The liquid chemical is swallowed.

Acute Exposure – Paraquat Poisoning

According to the United States Environmental Protection Agency (EPA), “one small sip [of paraquat] can be fatal and there is no antidote.” In general, people who accidentally or intentionally ingest paraquat may experience any of the following symptoms:

• Acute kidney failure
• Coma
• Confusion
• Heart issues
• Liver failure
• Lung scarring
• Muscle weakness
• Pulmonary edema
• Respiratory failure possibly leading to death
• Seizures

While these cases are rare, paraquat poisoning may also occur via skin contact or inhalation. This report out of China highlights the potential for paraquat poisoning via skin absorption, and this report highlights the potential for paraquat poisoning via inhalation.

Chronic, Low-Dose Paraquat Exposure

Most paraquat applicators who repeatedly use the herbicide as intended are exposed at chronic, low doses. Even at this level of exposure, paraquat herbicide is capable of causing severe side effects, including:

• Eye damage: Conjunctivitis, destruction of the ocular surface, and keratitis.
• Skin damage: Ranging from reddening and blistering to severe burns.
• Parkinson’s disease: Studies show that the risk of Parkinson's disease increases with long-term exposure to paraquat.
• Respiratory arrest: Ingestion of paraquat can cause lung fibrosis and death due to respiratory failure.
• Other damage: Paraquat can harm kidney, liver, gastrointestinal, and cardiovascular health.

Paraquat Toxicity – Lawsuits Allege Herbicide is “Unreasonably Dangerous”

The U.S. Centers for Disease Control and Prevention (CDC) describes paraquat as “toxic” and “highly poisonous.” While paraquat remains commercially available in the U.S., the EPA lists the herbicide as “restricted,” meaning only licensed applicators may use it. Despite the herbicide’s restricted status, paraquat lawsuits allege the herbicide is unreasonably dangerous, even when licensed applicators use the product as intended.

Paraquat Banned in Dozens of Countries

Paraquat is so toxic that at least 50 countries have issued bans, citing paraquat studies linking exposure to Parkinson’s disease and other serious health issues. In the U.S., however, paraquat use has reached an all-time high within the last 25 years. According to the U.S. Geological Survey, estimated annual use of paraquat in the U.S. reached 10 million pounds in 2017, doubling the annual use for 2013.

Paraquat is one of only two pesticide products still used in the U.S. that is either banned outright or phased out of use in the European Union, Brazil, and China.

Paraquat Parkinson’s Disease Link

The body of scientific research linking paraquat and Parkinson’s disease (often referred to simply as “PD”) has continued to grow in recent years. Several studies have concluded that exposure to paraquat increases the likelihood of developing Parkinson’s disease and that the effect is dose-dependent. The research suggests that farmworkers and pesticide applicators are more at risk of developing Parkinson’s disease. People who live near fields and other areas where paraquat is heavily used may also be more at risk for PD.

What is Parkinson’s Disease?

Parkinson’s disease is a progressive neurodegenerative disorder of the brain. One of PD’s hallmarks is the selective degeneration and death of dopaminergic neurons (dopamine-producing nerve cells) in the brain. Once dopaminergic neurons die, they are not replaced. The presence of Lewy bodies (insoluble aggregates of a protein called alphasynuclein) in many of the remaining dopaminergic neurons in the brain is also a hallmark of Parkinson’s.

When enough dopaminergic neurons have died, dopamine production falls below the level the brain requires for proper control of motor function, resulting in the motor symptoms associated with PD.

Presently, there is no cure for Parkinson’s. No treatment will cease its progression. The treatments most commonly prescribed for its motor symptoms tend to become progressively less effective the longer they are used. Parkinson’s treatments may also increasingly cause unwelcome side effects the longer they are used.

According to the Michael J. Fox Foundation, a person diagnosed with Parkinson’s spends an estimated $26,400 per year on their care. Additionally, Parkinson’s diagnoses in the U.S. result in an annual economic burden of $19.8 to $26.4 billion.

Parkinson’s Symptoms

Parkinson’s affects the motor system, which is the part of the central nervous system that controls movement. People with Parkinson’s may not notice the symptoms immediately as the disease manifests gradually and symptoms often worsen over time.

The most common Parkinson’s symptoms include:

• Resting tremor – Shaking movement when the muscles are relaxed
• Bradykinesia – Slowness in voluntary movement and reflexes
• Rigidity – Stiffness and resistance to passive movement
• Postural instability – Impaired balance

Parkinson’s can also result in “secondary” motor symptoms, which include:

• Freezing of gait
• Shrinking handwriting
• Mask-like expression
• Slurred, monotonous, quiet voice
• Stooped posture
• Muscle spasms
• Impaired coordination
• Difficulty swallowing
• Excess saliva and drooling caused by reduced swallowing movements

Other health problems related to PD include memory problems, sleep disorders, depression, pain, constipation, and other non-movement symptoms.

Can Paraquat Cause Parkinson’s Disease?

Yes, a growing body of medical research links chronic, low-dose paraquat exposure to Parkinson’s disease. In 2011, scientists reported that exposure to paraquat increased the risk of Parkinson’s by more than two-fold. Conversely, scientists in the Netherlands noted that the country had a decrease in Parkinson’s disease in the general population following a ban on paraquat.

How Does Paraquat Cause Parkinson’s?

Scientists generally agree that oxidative stress is a major factor in—if not the precipitating cause of—the degeneration and death of dopaminergic neurons and the accumulation of Lewy bodies, both of which are considered hallmarks of PD pathology.

Paraquat causes oxidative stress because of redox properties that are inherent to the chemical’s composition.

A strong oxidant, paraquat readily undergoes redox cycling (a repetitive process involving reduction and oxidation reactions) in the presence of molecular oxygen, which is plentiful in living cells. Paraquat’s redox cycling in living cells interferes with cellular functions that are necessary to sustain life with cellular respiration in animal cells. The redox cycling also creates a reactive oxygen species known as superoxide radical, an extremely reactive molecule that can initiate a cascading series of chemical reactions that creates other reactive oxygen species that damage lipids, proteins, and nucleic acids, molecules that are essential components of the structures and functions of living cells. Because paraquat’s redox cycling can repeat indefinitely in the conditions typically present in living cells, a single molecule of paraquat can trigger the production of countless molecules of destructive superoxide radical.

The same redox properties that make paraquat toxic to plant cells and other types of animal cells make it toxic to dopaminergic neurons in humans. Paraquat creates oxidative stress through redox cycling, which interferes with the function of, damages, and ultimately kills dopaminergic neurons in the human brain.

Scientists have known of paraquat’s redox cycling properties since the 1930s, and scientists have known that paraquat is toxic to human and plant cells due to its redox properties since the 1960s.

Studies Link Paraquat to Parkinson’s Disease

Epidemiological studies have found that exposure to paraquat significantly increases the risk of developing PD. Hundreds of in vitro studies (experiments in a test tube, culture dish, or other controlled experimental environments) have found that paraquat creates oxidative stress that results in the degeneration and death of dopaminergic neurons (among other types of animal cells).

A 2009 study on California Central Valley residents found evidence that exposure to a combination of paraquat and maneb (fungicide) increases the risk of Parkinson’s, particularly in younger subjects or when the pesticide exposure occurs at younger ages.

A 2011 study of participants in the large Agricultural Health Study (AHS) found an odds ratio of 2.5 increased risk among those who mixed or applied paraquat. If the research subjects had a defect in a specific gene, the risk for PD increased, the study found. “Our findings, considered together with earlier results, suggest that paraquat use plays a role in human PD. Because paraquat remains one of the most widely used herbicides worldwide, this finding potentially has great public health significance,” the study authors wrote.

A 2017 study found an association between paraquat exposure and PD, especially among individuals with certain genetic characteristics. The study further concluded that paraquat exposure damaged DNA and impaired mitochondrial respiration.

Paraquat is one of only a handful of toxins that scientists use to produce animal models of Parkinson’s disease. Animal studies have found that paraquat herbicide causes a dose-dependent depletion of dopamine among mice injected with the chemical, and the effect is long-lasting and irreversible.

If you would like more information on your legal rights, we offer free and fast paraquat Parkinson’s lawsuit consultations. Please fill out our contact form or call toll-free (855) 948-5098.