Prenatal Paraquat Exposure Can Cause Neurodevelopmental Toxicity Similar To Parkinson’s Disease: Study

New research suggests that prenatal Paraquat exposure can cause neurodevelopmental toxicity that could hinder brain development, signaling changes similar to Parkinson’s disease caused by the controversial weedkiller.

French researchers published a study online on this month in the medical journal Chemosphere, which looked at the side effects of Paraquat and nanoscaled titanium dioxide particle aerosols on gestating mice. While the researchers predicted the two combined could cause neurodevelopmental side effects in utero, they instead found Paraquat could cause a Parkinson’s disease-type of toxicity all by itself.

Paraquat was first introduced in the 1960s, and has been widely used on farms and throughout the agricultural industry. Due to the risk of Paraquat poisoning, which can cause fatal injuries if even a small amount of the herbicide is ingested, it has been heavily restricted in the U.S., requiring users to complete a training and certification program on the safe handling of the weed killer. However, in recent years, the weed killer has also been linked to an increased risk of Parkinson’s disease, suggesting it can cause some type of neurological damage or changes in the brain.

In this latest study, the researchers sought to determine if nanopesticides, which use engineered nanomaterials to make them more efficient and reduce their environmental impact, can infiltrate pregnant mice and affect their unborn pups in utero. They chose to test Paraquat and nanoscaled titanium dioxide particles, known as nTiO2, both of which are nanopesticides.

Researchers conducted tests on groups of gestating mice, exposing them to certain concentrations of one or both of the pesticides. They then looked for modifications in gene expression, which could cause neurodevelopmental changes in key areas of the brain.

While nTiO2 exposure resulted in minor neuroinflammation, Paraquat exposure was linked to key alterations in the brains of the unborn, the researchers found.

“The data suggest an alteration in the mitochondrial function following Paraquat exposure, which is reminiscent of the pathological process leading to Parkinson’s disease,” the researchers determined. “Based on previous toxicological knowledge and our observations, (Paraquat) may directly alter the mitochondrial function and the redox status in neurons, during fetal and early post-natal life, as it does in adult brain to induce Parkinson disease.”

Paraquat Parkinson’s Disease Risks

This is the latest study linking Paraquat to Parkinson’s disease, and the first to show its effects in utero. However, previous studies have also linked the weed killer to the neurological disease.

In 2012, researchers from UCLA found a link between pesticide use and a risk of developing Parkinson’s, indicating that individuals who suffered a traumatic brain injury (TBI) and were exposed to Paraquat were three times more likely to develop Parkinson’s disease.

Another study published in May 2013 found yet another link between pesticide exposure and an increased risk of developing Parkinson’s disease, indicating that pesticide exposure may increased the risk of developing Parkinson’s by 60 percent.

That study also found the risk increased with exposure to any type of pesticide, herbicide or solvent; but exposure to specific chemicals doubled the risk. Chemicals used in the test included Paraquat, Maneb and other pesticides.

In March 2016, the U.S. Environmental Protection Agency announced it would be re-evaluating the health risks with Paraquat, and a number of health experts and consumer advocacy groups have called on the agency to remove Paraquat-based herbicides from the market in the U.S. However, it continues to be used by farmers and other industries for weed and grass control, potentially exposing individuals handling, mixing or applying the Paraquat to life-long health risks.

The makers of the herbicide now face a growing number of Paraquat Parkinson’s disease lawsuits now being pursued in courts throughout the United States, each alleging that users may have avoided a diagnosis if warnings and safety instructions had been provided for farm workers and those living hear where it was regularly sprayed.

Parkinson’s disease affects more than 500,000 Americans, with approximately 50,000 new cases each year. The disease causes the loss of motor functions, causing imbalance and shaking, which gets progressively worse over time.