Effect of Heavy Metals

In 1998 a NIH study on 1,127 American military men clearly showed that the major contributor to human mercury body burden was from dental amalgam.
In fact, if one had 4-5 amalgams they accounted for 80-90% of the mercury body burden.
Further, analysis of mercury levels in the birth hair of infants showed the major contributor to be from the birth mother's dental amalgams.

Even the World Health Organization lists dental amalgam as the major contributor to human mercury body burden.

Articles on Mercury as a Heavy Metal Toxin

Now a comprehensive study in Canada (considered one of the world's cleanest nations) has found excessive levels of toxic metals in our food.

40 Page Report on Heavy Metals in Our Food and Environment

This report is from the non-profit organization, Environmental Defense Canada, which tracked a wide range of contaminants found in food. The group compared the amounts of heavy metals in the Canadian diet to intake guidelines established by the Environmental Protection Agency in the United States.
Environmental Defense Canada's assessment is that Canadians are consuming trace amounts of industrial metals like lead and cadmium, and it might be affecting our health.

Cadmium and lead, says the EDC's executive director, Burkhard Mausberg, are very toxic. "Two chemicals the body doesn't need," he says, "and the intake through food is higher that that which is safe."
Cadmium is a metal used in manufacturing and phosphate fertilizers. Researchers found that Canadians are, at times, eating four times the amount considered safe for cadmium consumption.
And young children, ages two to four, are apparently eating the most, in foods like shelled seeds, meats, cabbage, celery and peanuts.

Lead, for which there is no safe limit, is a metal used in manufacturing. It was found in raisins, muffins and beef. The highest levels of lead were found in salad oil, followed by cold cuts.

Environmentalists say the trace metals in food are the result of industrial pollution, which ends up - through precipitation or sewage runoff -- in the soil used to grow food or feed livestock.
"It's an important snapshot of where we're at with the environment," Sarah Winterton of Environmental Defense Canada told Canada AM on Monday. "We've got to get lead and cadmium and other heavy metals out of industry."
At higher levels, both lead and cadmium are linked to health problems. Concerns linked to lead include lowered IQ, behavioral problems, anemia and kidney toxicity. Cadmium is also a suspected carcinogen, Winterton said.

Health Canada says the levels found in foods are so low, they don't pose a risk. And University of Guelph scientist Beverly Hale, who researches trace metals in the environment, agrees. "All of the intakes on this study are below the maximum daily intake set by the World Health Organization," Hale told CTV News.
Still, environmentalists say we just don't know the long term effects.
"Are we going to find out for each child what the effect should be," asks Mausberg. "Or are we going to say we are not going to pollute our air and water."

Environmental Defense Canada is recommending that there should be a phasing out of heavy metals released into the environment, and that the government take steps to legislate maximum residue limits through the Food and Drug Act and Regulations.