More than 200 years ago, James Parkinson, a London surgeon, scholarly medical writer, and popular parish doctor, published a 66-page booklet entitled â€œAn Essay on the Shaking Palsy.â€ This book was the first clinical description of paralysis agitans, later named â€œParkinsonâ€™s diseaseâ€ eponymously.Â
We now know that a small percentage of patients develop Parkinsonâ€™s disease (PD) due to clear underlying genetic causes. However, more than two centuries following its original description, we still do not understand why most people develop PD.
Most experts agree that PD is caused by complex interactions between genetic and environmental factors. The latter may include exposure to toxins, including substances toxic to unwanted plants (herbicides), chemicals, heavy metals, or head trauma.
In recent years, paraquat, a popular herbicide widely used for weed and grass control across the United States, has been associated with an increased risk of PD.
Below weâ€™ll discuss the neurological disease PD, paraquat (a herbicide linked to increased PD risk), and why the latter is the subject of multiple lawsuits by product liability lawyers.
These attorneys currently represent agricultural workers, farmers, and others diagnosed with PD seeking compensation to ease the financial burden of a PD diagnosis, including lost wages, medical expenses, and more.
What Is Parkinsonâ€™s Disease?
First, itâ€™s essential to understand PDâ€™s potential severity and impact on quality of life. PD, a progressive neurological disorder, results when nerve cells (neurons) produce insufficient levels of the brain chemical dopamine, which sends messages between nerve cells (neurotransmitters).
It is associated with the degeneration of neurons in a region of the brain (basal ganglia) responsible for movement control, cognitive executive functions, and emotional behaviors.
Worsening over time, PD causes the gradual development of movement (motor) and non-motor symptoms. Although there is currently no cure for PD, multiple treatments are available that may help decrease and control symptoms.
What Are the Symptoms of Parkinsonâ€™s Disease?
The motor and non-motor symptoms associated with PD may vary in severity and progress differently.
Motor Symptoms Associated With Parkinsonâ€™s Disease
A range of motor symptoms may develop in association with PD, such as the following:
- Abnormally slow voluntary movements and reflexes (bradykinesia), making it difficult to perform simple daily tasks
- Stiffness and rigidity of the neck, shoulders, and limbs
- Impaired balance (instability of posture)
- Shaking movements of relaxed muscles (resting tremors), such as tremors of the hands and feet
- Gradual difficulties walking, where affected individuals may have shorter steps and drag their feet
- Loss or reduction of facial expressions (facial masking, also known as hypomimia)
- Abnormally cramped or small handwriting (micrographia)
Some patients with PD may also develop distinct changes in speech due to an abnormally weak voice, including the following:
- Speaking abnormally softly (hypophonia)
- Speaking hesitantly
- Speaking breathlessly
- Speaking in a monotone without standard inflections
- Difficulty enunciating letters and words (dysarthria) due to the impact of PD on muscles affecting speech
- Speaking quickly, with bursts of rapid stammering (tachyphemia).
Non-Motor Symptoms Associated With Parkinsonâ€™s Disease
Patients with PD may also have non-motor symptoms that impact their daily functioning. These may include the following:
- Gastrointestinal (GI) symptoms, such as constipation or abnormally slow movement of food from the stomach into the intestines (known as gastroparesis)
- Urinary difficulties, such as increased urinary frequency and urgency
- Reduced sense of smell (hyposmia)
- Vision changes, such as dry eyes, difficulty opening the eyes, or blurry vision
- Nerve pain, pain due to the development of prolonged involuntary twisting or muscle contractions (dystonia), or discomfort secondary to prolonged restlessness
- Sexual dysfunction
- Mood changes, such as anxiety, depression, or apathy
- An abnormal drop in blood pressure upon standing (orthostatic hypotension)
- Excessive drooling (sialorrhea) due to poor facial and oral muscle control
- Sleep difficulties, including insomnia, extreme daytime fatigue, acting out of dreams while asleep (REM sleep behavior disorder), or restless legs syndrome (RLS)
- Psychotic behaviors, such as delusions, hallucinations, agitation, or paranoia
Some PD patients may also develop cognitive impairment, such as slowed thinking, difficulty planning, confusion, visual-spatial difficulties, and difficulties with memory.
In some cases, cognitive impairment may progress, resulting in Parkinsonâ€™s dementia, which may be characterized by problems solving problems (executive functioning), slowed processing, memory loss, and mood changes.
In addition, some PD patients may develop previously â€œout-of-characterâ€ impulsive control disorders (ICDs), such as:
- Binge eating
- Increased sexual behavior (hypersexuality)
- Medicine abuse
- Excessive shopping
- Excessive computer use
- Excessive engagement in certain hobbies
ICDs may develop as adverse effects of certain PD medications (dopamine agonists). Therefore, immediately discuss such behaviors with the prescribing physician.
Because dopamine also impacts brain regions involved in feelings of reward, dopamine-agonist treatment may trigger impulsive behaviors due to enhanced reward-related memories.
What Causes Parkinsonâ€™s Disease?
So, what causes Parkinsonâ€™s Disease? Letâ€™s take a look at some of the most common factors.
Genetics and Parkinsonâ€™s Disease
In about 10 to 15 percent of cases, patients may inherit alterations (mutations) in specific genes that cause PD. Patients in certain populations may have an increased genetic predisposition for PD, including Ashkenazi Jewish and North African Arab Berbers.Â
However, if someone has inherited a genetic mutation linked to PD, the likelihood of developing the disease may be low. Some patients may have genetic alterations that may predispose them to the effects of environmental factors, triggering biological changes that ultimately lead to PD.
Environmental Factors and Parkinsonâ€™s Disease
There is compelling evidence to suggest that certain environmental factors may increase PD risk, although the specific compounds and underlying mechanisms remain unclear.
Traumatic Brain Injury and Parkinsonâ€™s Disease
Research suggests that sustaining a head injury that causes an alteration in consciousness (traumatic brain injury) may be associated with developing PD years following the patientâ€™s injury.
Perhaps the most famous example is the renowned boxer Muhammad Ali, diagnosed with young-onset PD. Experts have argued whether he developed PD due to multiple head injuries, additional environmental factors, genetic mutations causing a predisposition, or all of the above.
For example, exposure to paraquat soon after sustaining a TBI increases the risk of developing PD years later.
Further, in 2018, a study published in the medical journal Neurology added additional evidence supporting the link between TBI and an increased risk of PD. Investigators evaluated the medical records of over 325,000 veterans, where half had experienced a mild, moderate, or severe TBI. At the beginning of the study, none of the veterans had been diagnosed with PD.Â
However, twelve years later, nearly 1,500 veterans had been diagnosed with PD, and 949 experienced a TBI. After the investigators adjusted for age and other factors, including additional medical conditions, they found that a mild TBI increased the risk of developing PD by 56 percent. A moderate to severe TBI increased the PD risk by 83 percent.
Importantly, however, experiencing a TBI does not automatically indicate that an individual will ultimately develop PD. In the study noted above, fewer than one percent of veterans developed PD regardless of whether they had experienced a TBI, demonstrating a low overall risk of developing PD following TBI.
Multiple environmental factors are associated with an increased risk of PD, including:
- Head injury
- Certain pesticides
- Heavy metals
- Solvents (see below)
Yet research suggests that although such environmental factors contribute to an elevated risk of PD, they are not sufficient to directly cause PD themselves, requiring a complex interplay between such factors and specific genetic mutations.
Geography and Parkinsonâ€™s Disease
Investigators have found that there appears to be an increased PD incidence and prevalence in the Northeast and Midwest regions of the U.S.Â
Described as a â€œPD belt,â€ such nonrandom geographic PD distribution also strongly suggests environmental influences on the development of PD. Such geographic regions in the U.S. play prominent roles in industrialization and the use of herbicides and pesticides.
Occupations, Environmental Toxin Exposure, and Parkinsonâ€™s Disease
Now letâ€™s look at the environmental and occupational effects on Parkinsonâ€™s Disease.
Pesticides and Herbicides
Investigators have reported a link between exposure to specific chemicals in pesticides and herbicides and an increased risk for PD, such as the following:
- Organochlorine pesticides used for agricultural purposes, forestry, and mosquito control, such as beta-hexachlorocyclohexane
- Insecticides used in nets or clothing treated to kill mosquitoes, such as permethrin and rotenone
- Herbicides, such as the weed killer 2,4-dichlorophenoxyacetic acid and paraquat (please see the section entitled â€œWhat is Paraquat?â€ below)
- Agent Orange, a herbicide and defoliant used to remove leaves from trees and plants, contains 2,4-dichlorophenoxyacetic acid and other chemicals. The U.S. military used Agent Orange during the Vietnam War to defoliate forests concealing North Vietnamese and Viet Cong forces and to destroy crops.
Agent Orange exposure has been associated with the development of several diseases, including multiple forms of cancer, diabetes, and PD.
Although not definitively determined to cause PD, Agent Orange exposure qualifies members of the military for Veteransâ€™ Administration (VA) disability benefits, and the VA added PD to a listing of conditions possibly associated with such exposure.
Heavy Metal Exposure
In some occupations, exposure to certain commonly used heavy metals appears to be linked to an increased risk for PD. For example, manganese exposure may occur in particular fields, such as welding, smelting, or other vocations that require manganese ore grinding, resulting in fine dust.
High-dose manganese exposure, usually through inhalation, has been associated with the development of symptoms frequently associated with PD (parkinsonism), known as manganism. Such symptoms may include a staggering gait, rigidity, deteriorated speech, difficulties eating and drinking, and other abnormalities.
Trichloroethylene (TCE), a solvent once frequently used in multiple industries, has been associated with an increased risk of PD in factory employees with long-term exposures. (TCE has been used in dry cleaning, for metal degreasing, and in detergents and paint thinners.)Â
TCE has been identified as a cancer-causing (carcinogenic) agent to humans through all exposure routes and carries the risk of causing non-cancer toxicities to the central nervous system, including PD, the liver, kidneys, and immune system, and more.
In addition, studies have identified exposure to polychlorinated biphenyls (PCBs) as a potential environmental risk factor for PD, potentially more in females than males. PCBs are synthetic chemicals commonly used as insulators and coolants.Â
Although banned for decades, they are still present in the environment due to their long half-life, and you can find them in items manufactured before the ban. Investigators have reported the presence of high PCB concentrations in the brains of people with PD.
What Is Paraquat?
In the ongoing debate regarding potential environmental triggers for developing PD, one of the most newsworthy in recent years is the use of the common herbicide paraquat.
Introduced in the 1960s, paraquat is a widely used herbicide for grass and weed control. Because it kills most green plant tissue immediately on contact, it is one of the most popular herbicides in the U.S. used for commercial purposes.Â
Farmers and others often use paraquat for weeds resistant to glyphosate, used in a broad-spectrum glyphosate-based herbicide called â€œRoundup.â€
Initially produced by Monsanto and then purchased by Bayer, Roundup is now banned in more than 20 countries. Research suggests that Roundup is associated with an increased risk of certain cancers (e.g., non-Hodgkinâ€™s lymphoma and chronic lymphocytic leukemia [CLL]).
Although Roundup is not banned in the U.S., some states restrict its use or ban it altogether. Paraquat is increasingly popular among agricultural and other commercial operations, which has been attributed to an increase in glyphosate-resistant weeds as well as the many high-profile glyphosate-related lawsuits by attorneys representing clients who developed cancer after consistent exposure to â€œRoundup.â€ Bayer has also indicated that it will stop selling Roundup for residential use due to increasing and ongoing litigation.
Syngenta, the primary manufacturer of paraquat, promotes its herbicide throughout the U.S., other industrialized countries, and developing countries. More than 100 countries worldwide have used paraquat as an herbicide for multiple crops, including:
Paraquat is also used around commercial buildings, parkways, storage yards, and roadsides. In 2017, ChemChina purchased Syngenta, which is manufactured in facilities in China and the United Kingdom (UK). The use of paraquat is banned in China and the UK, although they allow its production for export.
More than 30 countries have banned the use of paraquat, including the European Union (EU) and Switzerland. Approximately 200,000 to 300,000 people are estimated to take their own lives every year through self-poisoning with pesticides.
Paraquat is one of the most popular agents for self-poisoning due to its acute, rapid toxicity, leading several countries to ban or never authorize its use as an herbicide.
Due to its high toxicity, the U.S. Environmental Protection Agency (EPA) heavily regulates paraquatâ€™s use, classifying it as â€œrestricted useâ€ by commercially licensed users only.
However, the U.S. has not banned paraquat. The Parkinsonâ€™s Foundation and the United Parkinsonâ€™s Advocacy Council sent letters to the EPA, urging the EPA to cancel the registration of paraquat use based on scientific evidence linking the herbicide to an increased risk of PD.Â
Yet in October 2020, the EPA re-approved the use of paraquatâ€“albeit with new measures to reduce the risks of its service to human health and the environment.Â
In addition to the growing number of personal injury lawsuits, Earthjustice sued the EPA for approving continued use of paraquat, citing its link to PD. Earthjustice represents farmworker and agricultural groups, health organizations, including The Michael J. Fox Foundation for Parkinsonâ€™s Research, and environmentalists.
What Is Paraquat Found In?
Paraquat is found in multiple herbicides used as weed killers. Farmers and agricultural workers frequently use paraquat to protect against invasive weeds, reduce labor, and produce various crops, including the following:
- Sweet potatoes
As noted above, paraquat is also used to control weeds in non-agricultural commercial settings.
Paraquat Herbicide Trade Names
Paraquat is frequently sold under the trade name Gramoxone. In addition to Syngenta, it is manufactured by several additional companies, including:
- Adama Group
- Altitude Crop Innovations LLC
- Chevron Chemical Company
- Drexel Chemical Company
- Helm Agro
- Innvictis Crop Care LLC
- Sinon USA, Inc.
- United Phosphorus
What Products Contain Paraquat?
Paraquat herbicide is sold under multiple herbicide trade names, including the following:
- Bonfire Herbicide
- Cyclone SL 2.0
- Marman Herbiquat
- Ortho Paraquat CL
Is Paraquat in Roundup?
No, there is no paraquat in Roundup and vice versa. However, both herbicides share many features:
- Both are highly toxic, effective herbicides widely used throughout the U.S.
- Both herbicides appear to be associated with severe health risks, including an increased risk of PD with paraquat exposure and a higher risk of developing non-Hodgkinâ€™s lymphoma or CLL due to Roundup exposure.
- Both are the subject of lawsuits, where attorneys allege that the manufacturers are marketing the herbicides without warning consumers about the known, associated health risks.
Who Has the Highest Risk of Paraquat Exposure?
The EPA has restricted the use of paraquat to certified pesticide applicators only and prohibits non-certified people working under the supervision of certified applicators from using paraquat (including mixing, loading, and applying paraquat or engaging in other paraquat-related activities).Â
Therefore, those at the highest risk of paraquat exposure are those who are certified pesticide applicators who mix, load, or apply the herbicide as part of their occupation, including the following:
- Agricultural workers
- Crop dusters
- Herbicide applicators
- Chemical mixers
- Tank fillers
Significantly, however, although no one in public can utilize paraquat, those who live near agricultural or other commercial settings that use paraquat may be exposed to the herbicide.
Research suggests that paraquat exposure from within 1,600 feet of a residence, including those who live near farms, in residential communities, and in rural areas, may cause a slight increase in risk for developing diseases.
Yet looking at the numbers may also tell another story. For example, in general, although farmers and agricultural workers have a significantly increased risk of developing PD, genetics almost certainly plays a role.
If exposure alone were the only risk factor, nearly all those chronically exposed to the toxin paraquat would ultimately develop PD, which fortunately is not the case. The reason some people who have long-term exposure to paraquat never develop PD, whereas others do, remains a primary question regarding the complex causes and associations responsible for an ultimate diagnosis of PD.
Why Is Paraquat So Dangerous?
Although paraquat is one of the most frequently used herbicides worldwide, it is highly toxic. It is classified as a non-selective herbicide, meaning that it kills plants indiscriminately.
In contrast, a selective herbicide may kill weeds but does not destroy valuable plants. Paraquat can remain in the environment for lengthy periods and may be toxic not only to â€œnon-targetâ€ plants but birds and other animals, including humans.
In fact, per the EPA, one small accidental sip of paraquat can be fatal, and currently, there is no known antidote. If inhaled or ingested accidentally, the result may be fatal paraquat poisoning.Â
Several accidental paraquat poisonings have been reported in the U.S. Such poisonings usually result from the transfer of paraquat into unlabeled bottles that people later mistook for traditional beverages.
Further, in some Asian, South and Central American, and Pacific Island countries, people have intentionally used paraquat to commit suicide by self-poisoning.
Per the Centers for Disease Control (CDC), ingesting small, moderate, or large amounts of paraquat may result in serious adverse effects in hours, days, or weeks.Â
In addition to ingestion, paraquat may also enter the body through the skin or lungs. Adverse effects may include the following:
- Heart failure
- Liver failure
- Acute kidney failure
- Fluid in the lungs
- Lung scarring
- Respiratory failure
- Increased heart rate
- Cardiac damage
- Muscle weakness
If individuals survive paraquat poisoning, they may be affected by severe, long-term organ damage.
Paraquat and Parkinsonâ€™s Disease
In addition to acute toxicity due to accidental or purposeful paraquat ingestion, inhalation, or contact, as discussed above, there is mounting evidence suggesting an increased risk of developing PD secondary to prolonged paraquat exposure.
Beginning in 2009, multiple studies have been published in medical journals, suggesting that prolonged chronic exposure to paraquat, primarily in agricultural workers and those who lived near farms, was associated with abnormally high rates of PD.
The strength of such evidence has led to a tidal wave of lawsuits against paraquat manufacturers. The plaintiffs include those who applied the herbicide for years and later went on to develop PD yet were not made aware of the following:
- Chronic exposure to paraquat could lead to injury or disease, including PD.
- Precautions were necessary to prevent such injury.
The paraquat attorneys who are suing Syngenta on behalf of their clients are holding Syngenta accountable, contending the following:
- The company should have known about the potentially toxic effects of paraquat exposure and its link with an increased risk of PD.
- The company neglected to warn paraquat users about the potentially toxic effects of herbicide paraquat exposure.
- The company designed and marketed the product negligently.
- The company failed to take responsible steps to protect its buyers and users from potentially toxic paraquat exposure.
How Many Paraquat Cases Have Been Filed?
Agricultural workers who developed PD following chronic exposure to the herbicide paraquat have filed hundreds of paraquat Parkinson lawsuits in federal and state courts. Further, the number of lawsuits is expected to double over the next year.
In addition, a Parkinsonâ€™s disease class action lawsuit, also known as multidistrict litigation (MDL), has been established that includes more than 380 cases.
Thousands of additional Parkinsonâ€™s disease lawsuits are expected due to chronic paraquat exposure. The class action MDL is anticipated to accommodate the plaintiffs, helping to consolidate pretrial proceedings, including witness depositions and discovery of evidence.
Because such litigation is still in the early stages, there have not been any settlements. Yet based on settlements regarding prior cases with similar injuries and claims, itâ€™s believed that the paraquat lawsuit settlement amounts in the highest settlement tiers could range from approximately $175,000 to $250,000.
Cases in the lower settlement tiers will receive lower settlement values. Such paraquat settlement awards could be given to ease the financial burden that plaintiffs have experienced due to ongoing medical expenses, lost income, and other expenses associated with disability.
When Will the Paraquat Lawsuit Be Settled?
Since weâ€™re still in the â€œearly days,â€ itâ€™s difficult to know when the courts may settle the paraquat litigation. However, based on similar class-action suits, a global settlement is not expected until late in 2022 or early in 2023 at the very earliest.
Over the next 18 to 24 months or so, the judge overseeing the paraquat MDL will preside over a consolidated fact discovery process that:
- Focuses on the scientific evidence presented for both sides
- Adds newly filed paraquat cases to the MDL
The judge will then work with attorneys for both the plaintiffs and the defendants to select a percentage of representative cases for jury trials.
Called bellwether trials, the results from these trials will be used as a basis to facilitate global settlement negotiations. If these trials result in victory for the plaintiffs, Syngenta may need to agree to a large total amount of moneyâ€“called a global settlementâ€“to settle the remaining paraquat cases in the MDL.
What Can You Do If Youâ€™ve Been Harmed by Paraquat Exposure?
If you believe that youâ€™re eligible to file a paraquat Parkinsonâ€™s lawsuit or join the MDL, youâ€™ll want to contact a paraquat lawsuit attorney immediately to determine whether you have a case.
Even more importantly, you must also ensure that youâ€™re receiving the medical treatment and support you need to care for yourself and that youâ€™re well enough physically and mentally to engage in such a lawsuit.
Fortunately, the attorneys at Stoy Law Group, PLLC, also known as the Warriors for Justice, have 30+ years of legal experience fighting for the rights of people like you, whether itâ€™s for product liability, personal injury, civil rights violations, or employment discrimination.Â
You can contact them today at (817) 820-0100 or complete a free case evaluation to see how they can help fulfill your unique needs, and get a paraquat lawyer today.