Scientists have found that fungicides caused mouse cells to show changes similar to those seen in autism and Alzheimer’s. Although a definite link to the disorders has not been proven, the news brings modern fungicides under fresh scrutiny.
Researchers exposed dishes of the brain cells to more than 300 different pesticides and fungicides and found that one class of fungicides, the strobilurins, produced patterns of genetic changes often seen in the human conditions.
Scientists at the University of North Carolina in Chapel Hill hoped the experiment might shed light on the kinds of substances in the environment that contribute to cases of autism. To their surprise, they found compounds that produced some genetic hallmarks of autism and neurodegenerative diseases at the same time.
The strobilurins have only been approved for use in the past 20 years, more than half a century after the first individual diagnosed with autism was announced in the medical literature. Since the fungicides arrived on the market, they have been sprayed in increasing quantities to protect crops such as cabbages, spinach, lettuce, kale, tomatoes, apples, pears and grapes.
While the fungicides produced autism-like and Alzheimer’s-like signatures in the way genes are expressed in mouse neurons, the relevance of the changes is unclear: the scientists have no evidence that the chemicals contribute to either condition.
“The study was designed to try and identify chemicals that could cause autism, but we in no way say these things do cause autism,” said lead scientist, Mark Zylka, whose study appears in Nature Communications.
“What this work provides is evidence that these chemicals are bad for neurons. They turn the same genes on or off that you see not only in autism brains, but also in neurodegeneration,” he added.
Far more research is needed to learn whether the fungicides pose any risk to human health, but Zylka’s screening procedure could already help environmental agencies highlight potentially harmful substances for closer study.
Jeannie Lee, a professor of genetics at Harvard Medical School, who was not involved in the work, said the study should serve as “a wake-up call to regulatory agencies and the medical community.” She added that the research had “wide-ranging implications, not only for autism and diseases such as Parkinson’s and cancer, but also for the health of future generations.”
Source: theguardian.com