A pesticide that has been found in breakfast cereals, oats and orange juice may be able to cause dementia symptoms in weeks.
Weed-killer glyphosate, which is the active ingredient in RoundUp, has long been linked to cancers and nerve damage. But much of the earlier research has focused on looking at people that interact with it every day like farm workers.
The new study, performed on mice, suggests even small amounts of exposure can have long-lasting effects.
Experts found rodents who were given for about three months saw Alzheimer’s-like changes to their brains which persisted for months.
Upon dissecting the brains, the researchers saw the chemical itself had gotten into the delicate tissue of the brain, where it likely caused inflammation, which caused nerves and brain tissue to decay, leading to the changes they observed after six months.
Patrick Pirrotte, a study author and director at City of Hope said: ‘These findings highlight that many chemicals we regularly encounter, previously considered safe, may pose potential health risks.
Foods that were found to contain glyphosate include Quaker oatmeal, Cheez-It and Tropicana orange juice, according to a separate analysis by Sokolove law, a personal injury and illness law firm.
A 2023 analysis from personal injury and illness law firm Sokolove Law compiled a list of products that had tested positive for glyphosate in the past. Outside the food items, they also said the chemical was detected in cotton products and bottled water.
Previous studies have mainly focused on dosing mice with high levels of glyphosate. Only certain humans, like farm or factory workers, are commonly exposed to high levels of the herbicide, the average person likely is exposed to much smaller amounts of the chemical daily, if at all
According to the US Geological Survey, about 300million pounds of the chemical are used in the country each year, on products like corn, soybeans, oats, alfalfa, cotton and wheat.
From there, it can accumulate in soil, water or stick to crops as they’re processed into food items.
The CDC estimates that about 81 percent of Americans had been exposed to glyphosate as of 2014.
Studies of this sort led the International Agency for Research on Cancer to classify glyphosate as ‘possibly carcinogenic to humans’, but the chemical is still approved for use by the EPA and considered safe.
It’s banned or restricted in European countries like Germany, Portugal and Spain.
Few studies have examined what impact lower levels of long-term exposure to the chemical might have.
That’s what the new research set out to examine. The paper included researchers from Arizona State University and City of Hope, a private research center in California and appears in the Journal of Neuroinflammation.
They fed mice two levels of glyphosate: one high level and one low level that would be closer to the levels humans contact the pesticide.
The mice were fed their dose every day for 13 weeks, and then researchers stopped adding glyphosate to their diet, and merely observed them for six months.
Consistent with older research, even six months after the researchers stopped feeding the mice the pesticide, the high-levels of glyphosate caused the mice to develop brain inflammation and Alzheimer’s-like changes.
However, the researchers found that there were similar, yet less pronounced, changes in the brains of the mice who were fed low doses of the chemical.
The researchers write that this inflammation could lead to the symptoms seen in dementia, where healthy brain cells become clogged with sticky plaques that lead to mass cell death and eventually, memory loss.
This could help explain why we’ve seen an uptick in memory-robbing conditions in recent decades, Dr Velazquez claimed.
Glyphosate has been used since the 1950s. It became more popular in 1996, when techniques for genetic modification became more advanced, allowing scientists to manufacture crops that were resistant to it.
Professor Pirrotte said: ‘Herbicides are used heavily and ubiquitously around the world.’
Because of how common these are, Dr Velazquez said: ‘our goal is to identify environmental factors that contribute to the rising prevalence of cognitive decline and neurodegenerative diseases in our society’.
Roughly 7million Americans are living with Alzheimer’s – and that number is expected to grow to 13million by 2050, according to the Alzheimer’s Association.
This projected growth makes it essential for science to investigate many possible causes for the disease, the study authors said.
Samantha Bartholomew, a PhD candidate at ASU who authored the study, said: ‘My hope is that our work drives further investigation into the effects of glyphosate exposure, which may lead to a reexamination of its long-term safety and perhaps spark discussion about other prevalent toxins in our environment that may affect the brain’.
Still, they cautioned, since the research was conducted in mice, it’s not certain that what’s observed in this study will be the same in humans. More research is needed.
