Reducing Mercury Toxicity

Mercury toxicity is a hot topic. Recent findings that 40 per cent of adults and 60 per cent of children have mercury levels over the WHO-recommended standards are alarming indeed. In particular, people are concerned about the mercury levels in the fish we eat. In 2005, the Hong Kong government published a study showing that over 5 per cent of school students ate unsafe levels of mercury from their seafood consumption. The government blamed the high fish consumers for overuse of seafood, and has done nothing more on the issue.

Mercury is accumulating in fish mainly owing to industrial pollution. In the human body it's a poison. We can tolerate a certain level daily because we excrete and detoxify the element in the liver and kidneys to some extent. However, there is a tendency for mercury to accumulate in fatty tissues. Unfortunately, fats are not only stored on our hips and waist, but the brain and nerves are also made up of essential fatty materials. Many of us have accumulated dangerous levels of mercury in these important areas, so we may need to look at ways of assessing the levels of mercury in our body. Removal of mercury toxicity from our body and brain may be an essential part of a health restoration programme.

Marine Sources of Contamination

The most common source of mercury contamination is polluted seafood, and it is becoming more and more difficult to find unpolluted fish. In the US, the FDA has cautioned pregnant women, lactating women and those of child-bearing age not to eat shark, swordfish, king mackerel and tile fish. All of these are contaminated with methyl mercury, the most dangerous form of mercury, which can cause birth defects and infertility. 

In Hong Kong, the government will not publish the lists of the mercury levels in local fish samples, despite having extensive test records. My correspondence with government officials concerned has drawn no response. I believe there is a cover-up protecting the seafood industry here.

The seafood known generally to be most contaminated and that we advise you to avoid are:

  • Flake (shark)
  • King mackerel
  • Tile fish (found often in fish balls)
  • Tuna, especially tuna steaks Swordfish

The safest fish in international tests are:

  • Salmon
  • Halibut
  • Haddock
  • Flounder
  • Cod
  • Hake
  • Atlantic and Pacific herring
  • Smelt
  • Lobster (except the tomalley, which can contain dioxin)
  • Canned 'light' albacore tuna (which is safer than fresh or frozen steak varieties of 'white' tuna)

Other Sources of Mercury

  • Amalgam (silver) fillings in your teeth. The HK government website item on the safety of mercury amalgams is farcical, flimsy and non-factual
  • Medical drugs, including many vaccines (many drugs use mercury preservatives)
  • Cosmetics such as skin-whitening creams, waterproof mascara and Clairol hair dyes
  • Household items such as mould-inhibiting paints, batteries, broken thermometers, felt mats and felt clothing or hats, some floor waxes and polishes, and some oil-based paints (particularly marine anti-fouling paints)
  • Many fungicides, herbicides and insecticides used in the garden
  • Many chemicals used in industrial and laboratory processes
  • Fumes from coal-fired power stations.

Is Mercury Really So Dangerous?

Mercury is extremely toxic, and it only takes a few grams in a single dose to kill you. Just some of the many symptoms associated with mercury contamination are:

A) Acute Toxic Exposure (an industrial accident situation)

Mercury compounds at high levels cause severe diarrhoea, often with kidney malfunction with cessation of urine production. Sub acute poisoning results in mild to severe erosion of the gastrointestinal tract, nausea and vomiting, bloody diarrhoea and shock, nosebleed and nasal inflammation.

B) Chronic Low-level Exposure (the type associated with contaminated seafood)

Chronic exposure to mercury involves the central nervous system (brain), such as:

  • Tremor and loss of hand-eye co-ordination
  • Loss of reasoning power, confusion and poor concentration, senile dementia
  • Constriction of the field of vision
  • Abnormal state of emotional instability, irritability
  • Various neuro-psychiatric disturbances, including anxiety and depression
  • Weakness and prolonged unexplained fatigue
  • Insomnia
  • Tingling or prickling of the skin
  • Problems with the sense of taste or smell
  • Multiple Sclerosis, Parkinson's Disease, muscular weakness, tremors, paralysis

Other symptoms affect the intestines, especially:

  • Loss of appetite and corresponding weight loss, nausea
  • Diarrhoea - sometimes with bleeding such as colitis
  • Irritable Bowel Syndrome
  • Intestinal infections such as parasites
  • Candidiasis – fungal or yeast infections of mouth, gut, vagina, skin etc.
  • Allergies (especially to foods)


  • Frequent sore throats/tonsillitis and oral infections 
  • Poor immunity, frequent infections or colds and ‘flu’s
  • Palpitations, angina, heart irregularities, high blood pressure
  • Arteriosclerosis (through damaging blood vessels)
  • Auto immune diseases – especially affecting the nerves
  • Infertility - in both men and women

So What Can You Do?

The first step is to assess the level of mercury toxicity in your system. Blood testing is only effective if the toxic exposure is very recent. The most simple assessment method is Hair Mineral Analysis. Results of such testing correlate closely to the levels of mercury in your body organs, the number of amalgam fillings you have and the amount of polluted seafood you eat. The World Health Organization recommends hair mercury levels under 2 parts per million (ppm) for adults and 1ppm for children.

Hair Mineral Analysis is not the best assessment method, but it is simple and rarely misses heavy metal toxicity problems. (A urine assessment method is more accurate, following ingestion of a certain medication. It is more accurate, but a little troublesome to do). You can arrange a Hair Mineral Analysis (costing $790) in our dispensary - an appointment is not necessary. 

The next step, if high mercury is identified, is to identify the sources of mercury contamination and to remove them. This means reducing or eliminating consumption of polluted seafood, and removing dangerous items in your immediate environment (see the list of sources above), if possible.

At some point, you should also consider having your mercury fillings replaced with modern white composite fillings. This is quite a complicated process, and it needs to be done very carefully (using a 'Rubber Dam' and some method of preventing you from inhaling the mercury vapour), because improper removal can make the contamination even worse! At IMI we have a list of suitable dentists in Hong Kong to whom we can refer you.

Also helpful in removing mercury from your system are nutritional and herbal supplements such as chlorella, selenium, NAC (cysteine), alpha lipoic acid and vitamins C and E.

More burdened individuals and those with neurological (nerve or brain) symptoms will need medical chelation agents. These are performed at IMI by Dr Nicholas Ng. Mercury levels are recorded by urine assessments during the treatments, which are continued until all heavy metals are removed. You can find articles about this issue of mercury chelation at Gordon Research.

Don't let the fact that mercury burden is a common issue fool you into thinking it is non-toxic and can be ignored. You do not want to lose your mind at age 60 or even 70 as a result of ignoring the problem! Think about it, and take preventive action now