Very few chemicals, minerals, and metals have been thoroughly tested for their
impact on human health. Almost all testing that has been done has focused on individual
chemicals, so there is very little understanding of how chemicals might act
in various combinations. It is probable that many toxic effects are dose-related; that
is, they are essentially harmless if we are exposed to them in very small amounts
or if they are present in our bodies in very small quantities. The theory is that toxic
substances can be safe as long as the amount remains below a certain threshold.
Unfortunately for many toxins, the level at which subtle adverse effects begin to
occur is not known or is poorly understood. Research strongly suggests that the
recommended safe exposure levels of many chemicals are set too high. For example,
for metals such as lead and mercury, levels that were once considered safe were
found to be too high—the trend is to set lower levels for safe exposure to many
environmental toxins.
It is known that we all have hundreds of chemicals in our bodies today, including
many that didn’t even exist a few decades ago. Many of these chemicals are stored
in body fat, so they are eliminated very slowly. Biomonitoring surveys by the Centers
for Disease Control and Prevention (CDC) have found traces of 265 environmental
chemicals in the bodies of Americans, including toxic metals like arsenic
and cadmium, pesticides, flame retardants and even perchlorate, an ingredient of
rocket fuel.
Writing in the New York Times in 2020, Jane Brody presented research that suggests
that an observed increase in Parkinson’s disease is linked to exposure to toxic
chemicals in industrialized countries. The increase in risk is especially prominent
after occupational exposures to industrial solvents and degreasing agents such as
trichloroethylene (TCE) and exposure to pesticides such as chlorpyrifos, rotenone
and paraquat.
Although more research is needed, it has become clear that developing fetuses,
infants, children, pre-teens, and teenagers are far more vulnerable to toxins in the
environment than adults. Exposure to even tiny amounts of some toxic substances,
at particularly vulnerable stages of development, can lead to significant
harm to human health. For example, reports suggest that some children’s congenital
heart defects may be associated with their mothers’ exposure to environmental
toxins during pregnancy.
The harmful effects of lead have been well documented and found to be proportional
to its concentration in a person’s blood. The primary route for lead exposure
to children is from oral ingestion via food, water, soil, dust, and flaking paint in
older houses that were painted with lead-containing paint. Both pre- and post-birth
exposure of children to lead has toxic effects and leads to impaired cognitive
development, reduced IQ, and increased non-adaptive classroom behavior. Heavy
exposures to lead can cause miscarriage, and even paralysis and blindness. Blood
lead limit recommendations have been decreased progressively from 60 μg/dl in the
1960s to the current U.S. and WHO guidelines of a maximum level of 10 μg/dl. The
banning of lead additives in paint and gasoline has reduced exposures from those
sources, but industrial emissions continue to cause environmental contamination
with lead.
Mercury, like lead, is toxic to the brain, especially to the developing brain. Significant
sources of mercury are coal-fired power plants and waste incinerators. Methylmercury,
the more toxic form of mercury, is produced by microorganisms acting
on mercury in deposits in the sea and the soil. Since mercury accumulates through
the food chain, the highest levels of methylmercury are found in large predatory
fish that are at the top of the food chain. These fish are a major source of human
exposure. Mercury exposure, especially during fetal brain development, can impair
children’s memory, attention, and language abilities and interfere with fine motor
and visual-spatial skills. The FDA and EPA advise pregnant women not to eat
swordfish, shark, king mackerel, and tilefish and limit consumption of albacore tuna
to 6 ounces or less a week.
This blog presents opinions and ideas and is intended to provide helpful general information. I am not engaged in rendering advice or services to the individual reader. The ideas, procedures and suggestions in that are presented are not in any way a substitute for the advice and care of the reader’s own physician or other medical professional based on the reader’s own individual conditions, symptoms or concerns. If the reader needs personal medical, health, dietary, exercise or other assistance or advice the reader should consult a physician and/or other qualified health professionals. The author specifically disclaims all responsibility for any injury, damage or loss that the reader may incur as a direct or indirect consequence of following any directions or suggestions given in this blog or participating in any programs described in this blog or in the book, The Building Blocks of Health––How to Optimize Your Health with a Lifestyle Checklist (available in print or downloaded at Amazon, Apple, Barnes and Noble and elsewhere). Copyright 2021 by J. Joseph Speidel.
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