Tuesday, December 24, 2013

How to Protect Yourself From Mercury Exposure

Mercury (Hg) has long been recognized as a neurotoxicant; however, recent work in animal models has also implicated Hg as an immunotoxicant. While there is presently no evidence to suggest that Hg induces frank autoimmune disease (AD) in humans. But the scientific evidence is mounting that Hg can be a co-factor in autoimmune disease by increasing the risks and severity of AD in the presence of other triggering events, either genetic or acquired.[1] Also, some studies have demonstrated a link between occupational Hg exposure and AD.[1,2,3]

In this article, we will discuss:
  • How do we come in contact with Hg?
  • How to avoid it?

How Do We Come in Contact with Mercury (Hg)?


Exposure to Hg varies among different people, but it is widespread because there are several ways you can come in contact with it:[4]
  • Hg is found in dental amalgam (also called silver fillings), cosmetics, pesticides, and some vaccines.[5]
    • Amalgam, which has been in use in dentistry for 150 years, consists of 50 % elemental Hg and a mixture of silver, tin, copper and zinc.[7]
    • High levels of exposure may also occur with the use of skin lightening creams that contain Hg.
  • As a pollutant which is released into the air from many factories, especially those that burn coal.
    • It then enters our environment and eventually our food supplies (hint: tuna and swordfish).
    • Inorganic Hg can be inhaled from breathing in mercury vapors.
  • Occupational exposure to Hg occurs in gold mining and in the factory process for purifying and making chlorine.
Hg can enter our bodies or blood streams in two forms:
  1. Mercury vapors
    • Dental amalgam is the major source of mercury vapor exposure
      • Studies have shown a direct correlation between the number of amalgam fillings and mercury concentration in the blood and urine.[5]
    • In the body, inhaled inorganic mercury from breathing in mercury vapors can accumulate in and have toxic effects on the nervous system and kidneys
    • Mercury vapors can cross over the blood-brain barrier very easily and accumulate in the brain
  2. Methylmercury
    • Methylmercury exposure is almost exclusively from seafood such as tuna and swordfish.
      • In a recent study, EWG found that almost 30 percent of their participants—who eat at least two meals of seafood, fish or shellfish every week —had too much mercury exposure according to Environmental Protection Agency guidelines for pregnant women.[13]
    • Research has shown a direct correlation between the amount of fish consumed and methylercury levels in the blood and hair.
    • This type of mercury is toxic to the brain but doesn't cross over the blood-brain barrier as easily as the inorganic variety; instead, it accumulates in other tissues of the body.
    • When you measure blood levels of mercury, if they are elevated, it is usually from methymercury.

All forms of Hg, once inside your cells, create free radicals, which are molecules that damage enzyme activity, cell membranes, and your DNA (the genetic code inside the cells). Also, pregnant women be warned that:
  • Both forms of mercury pass easily through the placenta from a mother to your unborn child
  • Research has shown that methylmercury is absorbed into the placenta and stored in the fetal brain in concentrations that exceed maternal blood levels
Figure 1.  70% of the global salmon market is farm raised (photo: Barron's

How to Avoid Mercury?


As we know there are different sources and forms for our Hg exposure, now let's get down to the business—How do we avoid it? As discussed in [4], here are Dr. Blum's recommendations:

  • Dental amalgam
    • If you have cavities with silver fillings, then make a plan with your dentist to remove all of them.
    • See [9] for the instructions of safe removal.
  • Fish
    • If you eat lots of fish, choose the less-mercury kind.
    • Check out [10] to see what fish to eat and what to avoid. For example, you should avoid tuna, swordfish, and Chilean sea bass.
  • Occupational exposure
    • Fairly strong associations were seen with self-reported occupational exposure to mercury and among dental workers.[2] So, you should wear quality surgical mask for the protection.
  • Pregnant women
    • You should avoid eating high-mercury fish. To get needed omega-3 fatty acid, you can take mercury-free fish oil supplements.[11]

Note that the health impacts are highly dependent on:
  • Which form of mercury you're exposed to
  • Your level of genetic vulnerability to toxins
If you have suffered any AD,[3] go ahead and buy a copy of Dr. Blum's book[4] to learn how to recover your immune system.[12]

References

  1. Mercury and autoimmunity: implications for occupational and environmental health.
  2. Glinda S. Cooper Et al. Occupational risk factors for the development of systemic lupus erythematosus. J Rheumatol 2004;31:1928-1933.
    • This study reveals the potential contribution of occupational exposures (mercury and pesticides) to the development of SLE.
  3. Mercury Exposures and Autoimmune Diseases (Travel to Wellness)
  4. The Immune System Recovery Plan by Susan Blum, M.D., M.P.H.
  5. The Pros and Cons of Flu Vaccination (Travel and Health)
  6. Relationship between mercury levels in blood and urine and complaints of chronic mercury toxicity from amalgam restorations.
  7. Amalgam risk assessment with coverage of references up to 2005
  8. Blood-Brain Barrier (Travel and Health)
  9. Academy of Oral Medicine and Toxicology
  10. Seafood Watch 2013 (Travel to Wellness)
  11. Omega-3 Fatty Acids (Travel and Health)
  12. Natural Immuninity Plays Important Roles in Your Health (Travel to Health)
  13. Mercury in Seafood (EWG)
  14. Mercury Poisoning Stories
  15. Decades of studies link mercury exposure to color vision loss