Neurotoxin Concerns, Controversy Escalate

Scientists are realizing that substances in the environment can have devastating effects on the human nervous system For decades, neuropathologist John Olney waged a one-man crusade to have "excitotoxins," chemicals in the brain that cause nerve cells to self-destruct, removed from foods. One of the worst, he argued, was glutamate, consumed by millions as the food flavoring monosodium glutamate. But nobody really paid much mind to Olney's concerns. The Food and Drug Administration (FDA) did no

Written byElizabeth Pennisi
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Scientists are realizing that substances in the environment can have devastating effects on the human nervous system
For decades, neuropathologist John Olney waged a one-man crusade to have "excitotoxins," chemicals in the brain that cause nerve cells to self-destruct, removed from foods. One of the worst, he argued, was glutamate, consumed by millions as the food flavoring monosodium glutamate. But nobody really paid much mind to Olney's concerns. The Food and Drug Administration (FDA) did not agree, and in 1970 judged the additive safe. So did, in that same year, a committee from the National Academy of Sciences (NAS).

But by 1980 scientists were beginning to realize that there were substances that warranted their attention. Lead in paint impaired learning. Epidemiological data revealed that Lucel-7, a substance used in making bathtubs, caused neurological damage in workers. In 1983, about 500 drug-users in San Francisco developed what appeared to be Parkinson's ...

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