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For a while now it's known that exposure to pesticides is associated with developing Parkinson's Disease. But which pesticides? This is an important question because millions of pounds of pesticides are applied in the US each year. A recent study provides some answers.

The Harvard and UCLA Health researchers looked at 288 pesticides. They found that 53 pesticides were associated with Parkinson's disease, but 10 were directly toxic to dopaminergic neurons. Dopaminergic neurons are cells in the brain, and their degeneration and death play a key role in Parkinson's disease.

The 10 most toxic pesticides included four insecticides (dicofol, endosulfan, naled, propargite), three herbicides (diquat, endothall, trifluralin), and three fungicides (copper sulfate [basic and pentahydrate] and folpet). Some are commonly used even by homeowners, such as Preen (contains trifluralin) and Ortho Groundclear (contains diquat).

They also found that co-exposure to several pesticides (which typically happens) have a greater negative effect than just 1 pesticide.

Bottom line: There is much we don't know about pesticides, but studies are finding more health harms each year. Avoid using pesticides in your home, lawn, and garden if you can - especially unnecessary "cosmetic" lawn pesticides. Best and safest is to use nontoxic Integrated Pest Management (IPM) or organic.

Think of it this way: pesticides can give you cancer and damage your health, but clover and crabgrass can't.

From Science Daily: 10 pesticides toxic to neurons involved in Parkinson's

Researchers at UCLA Health and Harvard have identified 10 pesticides that significantly damaged neurons implicated in the development of Parkinson's disease, providing new clues about environmental toxins' role in the disease. ...continue reading "Pesticides Involved in the Development of Parkinson’s Disease"

Dry cleaning Credit: Wikipedia

A widely used cleaning chemical (even in dry cleaning!) has been linked to Parkinson's disease by an international team of researchers. In a piece published in the Journal of Parkinson's Disease, they built a strong case that the chemical trichloroethylene (TCE) is one of the causes of Parkinson's disease. This is based on the existing evidence (both human and animal).

Trichloroethylene was widely used in the past (600 million lbs. per year at its peak in the 1970s), and is still widely used. It is environmentally persistent, and contaminates soil, air, and water. Vapors from underground water and soil contamination seep out into homes, schools, and workplaces. It is known to be carcinogenic (cancer causing) and associated with numerous cancers and other health harms, including birth defects.

TCE has had numerous industrial, consumer, military, and medical applications. For example, it is used in dry cleaning clothes, removing paint, as a degreaser, carpet cleaner, and engine cleaner. It even was used to produce  decaffeinated coffee in the past! Many US sites are now contaminated with TCE, including military bases.

The scientists point out that Parkinson's disease has increased so much (by 500%) that there must be exposure to something else (or more than 1 thing), and they find a strong link to TCE. They refer to Parkinson's as "the world's fastest growing brain disease".

By the way, a number of other toxic chemicals are associated with Parkinson's disease, (e.g., some pesticides, some drugs), long-term welding exposure, and even head trauma.

The researchers urge banning both the production of TCE and its use, urge the clean up sites that are contaminated with TCE, and more research.

Excerpts from Medical Xpress: Common dry cleaning chemical linked to Parkinson's

A common and widely used chemical may be fueling the rise of the world's fastest growing brain condition—Parkinson's disease. For the past 100 years, trichloroethylene (TCE) has been used to decaffeinate coffee, degrease metal, and dry clean clothes. It contaminates the Marine Corps base Camp Lejeune, 15 toxic Superfund sites in Silicon Valley, and up to one-third of groundwater in the U.S. TCE causes cancer, is linked to miscarriages and congenital heart disease, and is associated with a 500% increased risk of Parkinson's disease. ...continue reading "Common Cleaning Chemical Linked to Parkinson’s Disease"

Study after study finds all sorts of negative health effects from exposure to pesticides, including cancers, endocrine (hormone) disruption, and neurological effects.  Pesticide exposures can occur in the home, at work or school, in the air (drift), and in food and water. A recent study found that higher chronic pesticide exposure, such as occupational exposure (e.g. farm worker), is linked to developing Parkinson's disease.

University of California San Francisco (UCSF) researchers found the higher rates of Parkinson's disease both in people who have genetic susceptibility to developing the disease, and also in those who don't have a genetic susceptibility. Meaning everyone is at risk for developing Parkinson's disease with enough chronic exposure.

Studies find that chronic exposure to some pesticides has a higher risk for Parkinson's disease than others, and especially strong links are with the pesticides 2,4-D, chlorpyrifos, paraquat, glyphosate, and rotenone. Some countries, including in Europe and Canada, ban the use of some of these chemicals due to concerns about links to Parkinson’s, but the U.S. only restricts the use of some of them (e.g. paraquat).

Many pesticides are neurotoxins. Dr. Ray Dorsey (publisher of book: Ending Parkinson's Disease: A Prescription for Action ) said studies show a dose-response effect between chronic pesticide exposure and Parkinson's disease: "an almost perfect correlation between the amount of pesticides used in certain communities and the rates of PD. He points out that Parkinson's disease is the world's fastest growing brain disease with a lifetime risk of about 1 in 15. (That's high!)

Bottom line: Try to minimize your exposure to pesticides. Organic farms don't use the pesticides implicated in neurological harm - because organic standards don't allow it. Also, use organic or least-toxic Integrated Pest Management (IPM) for pest control in your home. Avoid using pesticides in your yard, especially the lawn. Stay away from recently pesticide treated areas. Eat organic foods as much as possible.

In the following article: sporadic Parkinson's disease means it happened spontaneously, which is different from someone having a genetic risk factor. From Beyond Pesticides: Pesticide Exposure Increases the Risk of Developing Gene-Specific and Sporadic Parkinson’s Disease Incidences

Research at the University of California San Francisco (UCSF) finds that pesticide exposure increases the risk of developing Parkinson’s disease (PD), regardless of whether disease onset is idiopathic (spontaneous) or genetic (GBA genetic risk variant). Although the exact etiology [cause] of PD remains unknown, epidemiological and toxicological research repeatedly identifies exposure to pesticides, as well as specific gene-pesticide interactions, as significant adverse risk factors that contribute to PD. Furthermore, this study, “Gene Variants May Affect PD Risk After Pesticide Exposure,” suggests that environmental triggers like occupational exposure to pesticides can prompt PD in individuals with or without the genetic precursor ...continue reading "Pesticides Linked to Parkinson’s Disease"

New research is raising questions about the role of gut bacteria in how people react to medications and whether the medicines are effective, at least some medications such as L-dopa treatment for Parkinson's disease. Why do medicines work for some people and not others? Perhaps the gut microbes are playing a part by interacting with the medicines! The gut microbes may actually be breaking down medicines and preventing them from reaching their target.

Researchers from Harvard University and University of California found that the composition of the gut microbes has an effect on whether the medicine L-dopa is effective or becomes ineffective as a Parkinson's disease treatment. They found that some bacteria can inactivate the medicine. Definitely research that needs following up on. Also, which medications is this true for?

Excerpts from Science Daily: Gut microbes eat our medication    ...continue reading "Gut Bacteria Has An Effect On Some Medicines?"

A number of studies have found that a poor sense of smell in older adults is linked to health problems (especially Parkinson's disease and dementia) and death. Now a recent study found that a poor sense of smell in older adults is associated with an almost 50% increase in their risk of dying within 10 years—especially in individuals reporting good health. In other words, a poor sense of smell is an early sign of deteriorating health, even when it is not apparent yet to the person.

Researchers at  the Michigan State Univ. College of Human Medicine  followed 2,289 persons (aged 71 to 82) for 13 years. The generally healthy persons took a smell test of 12 common odors (e.g. onion, soap, gasoline, lemon, chocolate and rose) at the start of the study, and were scored as having good, moderate, or poor sense of smell. After 13 years 1,211 of them had died. The researchers then looked to see if there was any association between scores on the smell test and their risk of death at various points over the 13 years.

No association was found at the three- or five-year mark of the study. But those with a poor sense of smell had a 46 percent higher risk of dying by 10 years and a 30 percent higher risk by 13 years, when compared with the older adults with a good sense of smell. The researchers believe the risk was lower at 13 years because so many of the participants had already died - whether their ability to smell was initially good or poor. So how to interpret the study results? It appears that a poor sense of smell may be a sensitive early sign of deteriorating health, even when it is not apparent yet.

From Medical Xpress: Poor sense of smell associated with nearly 50 percent higher risk for death in 10 years  ...continue reading "Is A Poor Sense of Smell In Older Adults A Sign of Deteriorating Health?"

A benefit (perhaps) of having the appendix taken out in childhood - it is associated with a lower rate of Parkinson's disease decades later in life, according to an international study that looked at health records of 1.7 million people in Sweden. Other main findings is that this finding is especially strong for individuals living in rural areas (and not urban areas), and that removing the appendix also delayed the age of Parkinson's disease onset in those who got the disease. But if you read further, there were other interesting findings in the study, even though much is still unknown - it's still a big puzzle with lots of pieces still to be filled in.

By the way, other recent research also supports the view that Parkinson's disease gets its start in the gut - and not in the brain, which is what everyone thought for years. But note that there are other risk factors such as certain pesticide exposure or drug use, or trauma to the head that are linked to Parkinson's disease. Many studies find that rural living is associated with a higher risk for Parkinson's disease, and it is thought this is probably due to higher exposure to pesticides, which then somehow contributes to the development of Parkinson's disease. From Medical Xpress:

Appendix removal is linked to lower risk of Parkinson's

Scientists have found a new clue that Parkinson's disease may get its start not in the brain but in the gut—maybe in the appendix. People who had their appendix removed early in life had a lower risk of getting the tremor-inducing brain disease decades later, researchers reported Wednesday.

Why? A peek at surgically removed appendix tissue shows this tiny organ, often considered useless, seems to be a storage depot for an abnormal protein—one that, if it somehow makes its way into the brain, becomes a hallmark of Parkinson's ...continue reading "Appendix Removal and Parkinson’s Disease"