“There's gold in them thar hills,” goes the old saying. There’s also human blood and nerve damage in that gold. And there's dying animals and destroyed rivers.

The greatest gold rush in all of human history is on. It's not a pretty, a romantic or a benign business. Indeed, it's a catastrophe for the environment and for human and animal health.

The high price of gold – it has tripled since 2000 – is such that every gold-bearing plot of land and river is being ravaged in more than 70 countries. As many as 50 million of the world’s poorest people now depend on  this kind of plunder for a living.

It's the mining equivalent of subsistence farming, but it's lethal in the cruelest ways. Mercury is used to identify the gold (2 grams of mercury for 1 gram of gold) to which it adheres. With each use, some of the mercury is washed away and vapor escapes into the air. In another variant of this practice, cyanide is used to leach gold out of ore in vats or ponds. Either way, two deadly substances are released without control into the environment.

The problem isn't with the deep mines of Australia, Canada, South Africa and the United States – the  hard-rock mines. It's with two other categories of mining that use mercury or cyanide: alluvial and artisan.

Alluvial is working a river with pans and sluice tables, which are primitive devices that trap gold granules in a blanket or grease. Artisan – a term used by the United Nations and environmental groups — uses bigger machines and expensive “shaker tables,” which process earth by the ton rather than the bucket. These can be found in surface gold deposits in rivers and farther away. This is a mechanized version of finding gold that is not deep in the ground.

While artisan mining may conjure images of dedicated craftsmen coaxing gold out of rock with love and skill, don’t be deceived. The activity is savage and brutal; the plundered rock and soil is left to wash away, causing death and destruction over many years.

The Natural Resources Defense Council in Washington, and its cohorts at the U.N. Development Program and the World Bank, consider cyanide to be the lesser of the two threats. Maybe. But I've seen great piles of mining spoil which the cyanide has rendered lifeless. Nothing lives in it or grows on it.

Certainly, mercury is the largest of the real-and-present danger of subsistence mining. In Indonesia, men stand in rivers with their hands in buckets of water, muck and mercury, according to one Associated Press report. The BBC also has reported promiscuous use of mercury in Indonesia and Peru.

From China to Romania, in much of Latin America and throughout Africa, there is extensive mining on the surface — and that means mercury use. Miners in these countries are well aware of the dangers — miners often are. But the economics of their lives dictate that they mine until it kills them, or the food chain collapses and their families are poisoned, or the operation has to move to a pristine area to be repeated.

The economic life that sustains also destroys.

The United States and the European Union have restricted the export of mercury. But that's only  increased the price, while there appears to be plenty in international trade – enough for the nomadic miners of those 70 or so countries.

I have to declare a personal interest in alluvial gold mining at its simplest: panning and sluicing. My father, whenever his many little business endeavors failed, headed for the beautiful Angwa River in Zimbabwe, both before and after World War II, to look for gold. He mined it with picks, shovels, pans and sluices. The activity was so minor it left no lasting mark. In those days gold fetched $35 an ounce, hardly enough to sustain him and his family, but better than nothing. Now it's about $1,600 an ounce.

My father loved that river. He often spoke about its beauty and tranquility. I've been reviewing photographs of it today: a ravaged moonscape of pits and waste piles. Crime is unchecked, murder is common.

Shakespeare said it: “All that glisters is not gold.” Indeed not. – For the Hearst-New York Times Syndicate