Brain & Drugs

Environment and Chemicals

Researchers from the Harvard School of Public Health suggested in 2006 that fetal and early childhood exposures to chemicals in the environment can damage the developing brain and can lead to neurodevelopmental disorders. They described 202 chemicals that have the capacity to damage the human brain and concluded that chemical pollution may have harmed the brains of millions of children worldwide. [i]

Concern about disease-causing effects of agricultural chemicals has been expressed for several decades. In 1982, for example, Alan Anderson [ii] reviewed the importance of nervous system toxins from the environment in causing mental malfunction. He stated: "Of the 100,000 or so chemicals used by American industry, 575 are deemed dangerous in large doses and many of these are known to be associated with catastrophic illness, from cancer to respiratory disease. Perhaps no class of chemicals is more subtle and treacherous in its effects, however, than neurotoxins, which can damage the nervous system even in modest doses and cause a variety of behavioral and emotional symptoms - among them, hallucinations, loss of memory, confusion, depression and psychosis."

There are several groups of pesticides used to control insects, weeds, and fungi. The chemicals are classified by target organisms as insecticides, herbicides, fungicides, or fumigants. Insecticides are classified by chemical type as organophosphates (OPs), organochlorines, carbamates, and pyrethroids. Direct exposure to these chemicals when they are spayed on crops, forests, residential area, and used in and around the home are more obvious and more toxic that indirect exposure to low concentrations by drinking contaminated water and eating contaminated food. The effect of agricultural chemical contamination of the food supply is not known. Individual sensitivity to contaminant chemicals varies and is interactive with other chemical stressors. Some pesticides are longer-lasting than others and can be generally distributed in the environment. DDT use, for example, is banned in North America, still shows up, carried on air currents from distant countries who continue to use it. Organochlorines have a long half-life, and serum levels can be used as a general marker of exposure to pesticides.

The biological effects of low levels of agricultural chemicals in the human body are uncertain. No authority can assure you that all is well. [iii] Chronic exposure to low but cumulative doses of chemicals may lead to chronic illness, and sooner or later, avalanche into catastrophic illness. People who use pesticides on regular basis risk toxicity and should reconsider this use. Individuals are frequently exposed to many different pesticides or mixtures of pesticides repeatedly over many years.

Common pesticides (Malathion, Parathion, EPN, Schradan) are related to nerve gases (Saran, Soman), which all block the breakdown of acetylcholine in synapses, so that it accumulates and blocks receptors. The result of a large dose is respiratory failure and convulsions, quickly fatal if the dose is high enough. Acute poisoning would only occur in people exposed to high concentrations of these chemicals in agriculture and industry. Kamel and Hopping summarized the problem: “Pesticides are used extensively throughout the world. In the United States, more than 18,000 products are licensed for use, and each year more than 2 billion pounds of pesticides are applied to crops, homes, schools, parks, and forests. Such widespread use results in pervasive human exposure. Evidence continues to accumulate that pesticide exposure is associated with impaired health. Occupational exposure is known to result in an annual incidence of 18 cases of pesticide-related illness for every 100,000 workers in the United States. The best-documented health effects involve the nervous system. The neurotoxic consequences of acute high-level pesticide exposure are well established: “Exposure is associated with a range of symptoms as well as deficits in neurobehavioral performance and abnormalities in nerve function. Whether exposure to more moderate levels of pesticides is also neurotoxic is more controversial. Pesticide exposure may also be associated with increased risk of neurodegenerative disease, particularly Parkinson disease.” [iv]

Sixteen pesticides have been detected in eight brand-name baby foods In the USA, according to a study by the Environmental Working Group (EWG) and the National Campaign for Pesticide Policy Reform (1997). A random sampling of 76 jars of baby food from grocery store shelves in Denver, Philadelphia, and San Francisco revealed that 53% had traces of one pesticide, and 18% had two or more pesticides. Plums contained the highest amounts at 46 parts per billion and peaches contained 29 parts per billion. The EWG was concerned that pesticides are not “tested for safety in the way babies are exposed to them," and that babies and young children "react differently than adults to many drugs and toxic substances."

Lead, mercury compounds, pesticides, herbicides, fungicides, aluminum, styrene, tetrachlorobiphenyl, and dioxins are among the neurotoxins that may be airborne and contaminate the food supply. The Environmental Protection Agency in the USA reported that the magnitude of chemical contamination of the USA in 1987 was 9.7 billion pounds of chemicals into streams and 2.7 billion pounds into the air. The allowance of toxic chemicals for each citizen was about 50 pounds. Despite concern about chemical toxicity, little has changed in the last 3 decades except that more chemicals have been added to the environment. Individual sensitivity to contaminant chemicals varies and is interactive with other chemicals entering the body.

[i] Grandjean et al. Developmental neurotoxicity of industrial chemicals. Lancet. Nov. 8, 2006. Also see online Department of Environmental Health, Harvard School of Public Health, Boston, MA, USA A Silent Pandemic: Industrial Chemicals Are Impairing the Brain Development of Children Worldwide. http://www.hsph.harvard.edu/neurotoxicant/appendix.doc

[ii]Anderson A. Neurotoxic Follies. Psychology Today July 1982: 30-42

[iii]Morgan DP Minimizing occupational exposure to pesticides: acute and chronic effects of pesticides on human health Residue Reviews 1980; 75:97-102 Springer-Verlag N.Y.

[iv] Freya Kamel; Jane A. Hoppin. Association of Pesticide Exposure With Neurologic Dysfunction and Disease. Environ Health Perspect 112(9):950-958, 2004. © 2004 National Institute of Environmental Health Sciences. Freya Kamel and Jane A. Hoppin are at the National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina, USA .


  • You are viewing the Brain Drugs at Alpha Online. Understanding the human brain is essential to become a well-informed, modern citizen. Stephen Gislason MD, the author of the Human Brain, is a physician-writer who is good at making complex subjects more understandable. This is a book with important ideas, so be prepared to read and then keep the book as reference.
  • Alpha Online is a Division of Environmed Research, founded in 1984 at Vancouver, BC, Canada. Online Since 1995.
    Alpha Nutrition is a trademark and a division of Environmed Research Inc.
  • Download The Human Brain as an eBook

    All Alpha Education and Persona Digital books, eBooks and Starter packs are ordered online. Prices are listed in Canadian Dollars.
    US $ cost is lower depending on the daily dollar exchange rate. Physical shipments by the Post Office are available to all destinations in the USA and Canada.
    We are located in Sechelt, close to Vancouver, British Columbia, Canada.  eMail:alphaonline@nutramed.com

    Brain Rescue Starter Pack

    This starter pack includes the Alpha Nutrition Program, the Human Brain in Health and Disease and one 500 Gram jar of Alpha DMX. There are a host of clues that link the food supply to mysterious and threatening neurological diseases. We suggest that a prudent person suffering early brain-dysfunction symptoms would be wise to pursue vigorous, thorough diet revision at the earliest opportunity. Because some brain dysfunction compromises judgment learning and motivation, family members, friends and professional advisor often have to initiate diet revision and provide the right direction and support.

    Order Brain Rescue Starter Pack


  • Order Persona Digital Books

    Click the Add to Cart buttons on the left to begin your order for printed books from Alpha Online (mail delivery to US and Canada).
    Download eBooks
    Click the Download button to order eBooks (PDF file) for download. Click book title (center column) to read topics from each book.

    Print Book" Read Topics Download
    Human Nature
    The Good Person
    The Puzzle
    Sound of Music
    Surviving Humans
    Language & Thinking
    I and Thou
    Emotions & Feelings
    Neuroscience Notes
    Human Brain
    Children & Family
    Intelligence & Learning
    Religion 21st Century

Further reading: Neuroscience Notes, Intelligence and Learning, Language & Thinking

Persona Digital

Persona Digital Books is the publisher of The Human Brain, Neuroscience Notes, Intelligence & Learning and related books.