New evidence unearthed by Dr Jack Levenson, the dentist who has led the fight against amalgam fillings in the UK, shows that dental fillings could be behind the burgeoning of many 20th century conditions
It is generally accepted that when a disease such as influenza reaches 400 per 100,000, or 0.4 per cent of the population, it is then considered to be of epidemic proportions. In January 1997, the British Dental Association (BDA) issued a fact file on mercury, stating: "About 3 per cent of the population are estimated to suffer from mercury sensitivity. "
Three per cent of the UK population alone would represent some 1.75 million people, of whom about one million would have mercury amalgam fillings.
Despite these potentially huge casualties, no action is taken on mercury toxicity and, unlike BSE and AIDS, it has atttracted relatively little media attention. No public money has been allocated for research.
Nevertheless, current research suggests that mercury vapour from fillings may be one of the predominant underlying causes of a broad spectrum of conditions, ranging from gum disease, migraine, headaches, poor memory, depression, anxiety, mental lethargy, chronic fatigue, growth, allergies such as eczema and asthma, and sensitivity reactions to food and inhalants, to rheumatism, arthritis, backache, kidney disease, Alzheimer's disease, Parkinson's disease, multiple sclerosis and other neurological disorders.
Some research has focused on particular problems among women exposed to mercury. One study showed that such women experienced disturbances in the menstrual cycle such as excessive blood flow, irregular periods, premenstrual tension (PMS) and painful menstruation (Pediatr Akush Ginekol, 1971; 33: 56-8). Another showed a higher than expected incidence of spontaneous abortion and premature labour (Gordon A, "Pregnancy in Female Dentists A Mercury Hazard", presented at the International Conference of Mercury Hazards in Dental Practice, Glasgow, 1981) in women exposed to mercury compared with controls. Their rate of failure of ovulation was also nearly double that of the controls (Akush Ginekol, 1974; 13: 20).
Tests were carried out at the University of Heidelberg on women who had hormonal irregularities and amalgam fillings and who had difficulty in conceiving. At the same time, blood samples were investigated for levels of pesticide contamination. The women tested showed higher levels of urine mercury when given a test that measures the amount of mercury excreted through a chelating agent.
The most common problem by far was mercury contamination, which correlated with the number of amalgam fillings. After removing the fillings, nutritional support and treatment of other environmental contamination burdens, 70 per cent of the women became pregnant without the aid of hormonal therapy (Gynakologie, 1992; 14: 593-602).
Further tests carried out at the University of Heidelberg involved 132 women with amalgam fillings who had abnormal hair growth or hair loss. Nearly half 49 per cent of these women showed significantly elevated mercury levels. After removal of their fillings, the symptoms disappeared in 68 per cent of cases (Klin Labor, 1992; 38: 469-76).
But it is not only women who suffer infertility problems caused by mercury. It has been estimated that about 50 per cent of infertility problems are associated with defective male sperm motility (Pharmacol Toxicol, 1988; 69: 440-4). Research has directly pointed to mercury.
Workers who are occupationally exposed to mercury vapour have been found to have a significant reduction in fertility rate (Am J Industr Med, 1985; 7: 171-86).
Mercury and the heart
Heart attacks were practically unknown in the nineteenth century a time when the general diet was high in fat and dairy products.
There is no full explanation for the substantial increase in heart disease, but the suspect factors are mainly diet, stress, smoking and general lifestyle.
Increasing evidence points to amalgam fillings as one major contributory factor.
A series of studies carried out at Washington University (Proc Soc Exper Biol Med, 1965; 120: 805-8; Proc Soc Exper Biol Med, 1967; 124: 485-90; Am J Physiol, 1970; 219: 755-61; Am J Physiol, 1971; 220: 808-11) demonstrated that mercury causes hypertension by contracting smooth muscle in arterial walls. Inorganic mercury caused blood vessel constriction and subsequent hypertension within minutes of exposure organic mercury did not. The work was subsequently confirmed by researchers at Harvard Medical School (Am J Physiol, 1975; 229: 8-12).
In 1974, the National Institute of Health, part of the US Department of Health, Education and Welfare, published a 333 page account of research in the Soviet Union on the effects of chronic exposure to mercury and its compounds (Cardiotoxic Effects of Mercury, DHEW (NIH) Publication No 74-473, 1974, pp 109-34, 199-210). They reported that mercury affected the function of the heart in a variety of ways, including the ability of heart muscle to contract, and its electrical conductivity and regulation of cardiac activity.
The Soviet researchers also found that mercury produced functional changes in cardiac activity and in heart muscle, and that it accumulated in heart muscle and valves. The damage was evident from ECG changes and through histological studies. They found that heart function was influenced by the effect of mercury on hormones from the pituitary gland.
In 1983, work carried out at the medical school at Lodz in Poland (Thromb Res, 1983; 30: 579-85) found that various mercury compounds in low concentrations accelerated blood clotting.
In 1990, Siblerud (SRI Total Environ, 1990; 99: 23-35) compared subjects with and without amalgam. They found that those with amalgam had significantly higher blood pressure, lower heart rate and lower haemoglobin counts. They also had a greater incidence of chest pains, tachycardia, anaemia and fatigue, and became tired easily and awoke feeling tired. The researchers concluded that: "The data suggest that inorganic mercury poisoning from dental amalgam does affect the cardiovascular system".
Mercury and the immune system
In 1984, David Eggleston, Associate Professor at the Department of Restorative Dentistry, published a preliminary report which demonstrated the ability of amalgam and nickel to affect the total percentages of T cells (J Prost Dent, 1984; 51: 617-23) those cells which help killer cells to recognise foreign invaders. Two cases involving dental amalgam, and one involving nickel, were presented. The results were similar in all cases. In one of Eggleston's 21 year old patients who had six amalgam fillings, 47 per cent of lymphocytes were T lymphocytes with amalgam fillings. After removal of these fillings, 73 per cent of lymphocytes were T lymphocytesan increase of 55.3 per cent.
When four amalgam fillings were again placed in the patient, the T lymphocyte count dropped to 55 per cent a decrease of 24.7 per cent. When the patient's amalgam fillings were replaced with gold, the T lymphocyte count rose from to 72 per cent an increase of 30.9 per cent.
The most recent research (Int J Occup Med Tox, 1995; 4) involving 34 patients with CNS disorders indicated intoxication from dental amalgam. Tests showed pathological findings in 88 per cent of these patients, of whom 60 per cent showed an immune reaction to mercuric chloride. These findings support the view that chronic low level exposure to mercury can compromise or weaken the immune system and adversely affect the defence mechanisms of the body.
ME and chronic fatigue
Mercury may contribute to chronic fatigue conditions and, in some cases, play a predominant role. Chronic fatigue is one of the main presenting symptoms of mercury toxicity, and practitioners expect the condition to improve when fillings are removed. Patients who are severely ill, and often bedridden and test positive to mercury find that symptoms improve to a varying degree when amalgam fillings are removed, but are not cured unless mercury is the predominant factor.
In one instance, a 42 year old GP had been housebound for four years with severe chronic fatigue syndrome (ME). She could only leave home for short journeys using a wheelchair, and had great difficulty in climbing stairs. She had 13 amalgam fillings and tested positive to mercury on a lymphocyte response test. Besides ME symptoms, she also complained of other symptoms such as burning mouth, blurred vision, nausea, constant low grade diarrhoea, muscle pain, depression, tension, irritability, poor memory, low blood pressure, asthma, sinus pain, aching joints and allergies to a range of chemicals.
The patient had all her amalgam fillings removed and, three months later, reported that her physical and mental energy had improved and that her nausea was completely cleared. She was also enjoying her food for the first time in years. The day after her final fillings were removed, her husband gave her some soup. She was amazed that it was the same soup her husband had given her the day before, which she had found tasteless. She also reported that her muddle headedness and lack of concentration had improved, and that she felt much more relaxed. Two years later, the patient confirmed that her improvement had continued.
Whether mercury was the initial cause of her chronic fatigue is a matter of conjecture. What this case illustrates is that even though, in some cases, mercury may not be the predominant causative factor, it can exacerbate an existing condition.
Bacterial resistance to antibiotics
A survey of 356 patients who had not recently been exposed to antibiotics showed a high prevalence of mercury resistant bacteria. They were also significantly more likely to concurrently have resistance to two or more antibiotics (Antimicrob Agents Chemother, 1988; 32: 1801-6).
These findings prompted a three university collaborative investigation in primates (Antimicrob Agents Chemother, 1993; 37: 825-34). This showed that a large proportion of common oral and intestinal bacteria became resistant to mercury two weeks after receiving amalgam fillings. Nearly all the mercury resistant bacteria were resistant to one or more antibiotics such as tetracycline, ampicillin, streptomycin and erythromycin. As in the human study, the monkeys had not had recent exposure to antibiotics, demonstrating that the bacteria had become antibiotic resistant due to exposure to mercury from dental amalgam.
In both studies, the proportion of mercury and antibiotic resistant bacteria declined markedly during the two months after amalgam removal.
These studies confirm earlier work carried out in Japan (Antimicrob Agents Chemother, 1997; 11: 999-1003; Appl Environ Microbiol, 1977; 33: 975- 6; Nature, 1977; 266: 165-7) which showed that the bacterial resistance to antibiotics and mercury can be transferred to other bacteria by strands of DNA. The mercury resistant bacteria constantly recirculate the mercury as vapour exacerbating the increase of antibiotic resistant bacteria. Thus, the situation cannot improve until the source of the mercury is removed.
In a recent paper (Sci Prog, 1997; 80: 103-6), a team from the Eastman Dental Institute pointed out: "It must be remembered that oral streptococci are a major cause of infective endocarditis with a high mortality". The general systemic consequences of the inability of antibiotics to contain or eliminate these resistant bacteria, commonly called 'superbugs', is an escalating and serious problem. The role of mercury in their growth should not be ignored.
Research has shown that mercury from dental amalgam fillings:
Increases mercury resistant bacteria, resulting in the constant recycling of mercury in the body;
Increases antibiotic resistance in bacteria the superbugs with obviously more serious consequences;
That bacteria are capable, via DNA strands, of transferring their resistance to other neighbouring bacteria; and
Mercury in the body and antibiotic resistant bacteria markedly decline after removal of mercury amalgam fillings.
!ADr Jack Levenson
Dr Levenson is author of Menace in the Mouth, published by and available from WDDTY (£9.99 + p&p). He will be speaking on the latest dangers of mercury and fluoride on May 4 at Friends' Meeting House in London. For tickets or his book, contact WDDTY at 020 8944 9555.