Tales Of Our Times: When Poisons Move, Risks Evolve

Tales of Our Times
New Mexico Citizens
for Clean Air & Water

When Poisons Move, Risks Evolve

Toxic materials in nature are like a stack of ball bearings on a subway platform. They pose little risk until they start to move.

Follow the trail of the Earth’s store of hazardous materials and the shuffling that moves them through the air and water. The forces are geologic history, weather, time, and inexorably man. Without man’s doings, toxic substances are widely found in nature, in some places more than others. The bad stuff ranges from arsenic, sulfur, mercury and uranium to selenium (as in locoweed), oil, asbestos, common table salt, and more. The raw agents vary greatly in toxicity and abundance, as well as in usefulness.

Over eons, shifting patterns of mountains, valleys, seas and climate settled the Earth’s toxic ingredients in safe places. Safe stowage is often found beneath rock, above other rock, and as specks locked in the rock itself.

Nature used air, sun and rain to clear away the hazards for man. Slowly, slowly the surface rock weathered into soil and rains leached away the poisons, creating fertile topsoil.  For the most part, the poisons stayed safely tucked away, except when an occasional volcano stirred the pot and spread them around.     

Then man walks on the scene. He starts digging around and in a twinkling of geologic time finds things he can use. He hits on salt, which he discovers can preserve food or poison a neighbor’s land. In due course, he comes upon iron, gold, copper, … sulfur, sulfur-bearing coal, … oil, uranium. 

To free the useful metals bound in ore, rock that lay underground for ages is cracked, hauled up, crushed, processed, and heaped on the land again. The problem is people now live nearby. The air, sun and rain again set to work on the specks of poisons in the rock piled at the surface. Sulfur, oxygen, water, sun, and time produce acid that leaches and frees the heavy metals to flow, as they will, to nearby streams or down to aquifers.

The transport of toxics by chance is an unwanted side effect of getting materials we want to use. To lessen the side effects, laws evolve.
Materials extracted for use also do harm when too much finds its way to people, wildlife, or their water and food. History records the major damage from industrial mercury dumped in Japan’s Minamata Bay and from oil spills on shorelines of many countries. Smaller incidents are less drastic, but are far more frequent. They include toxic drilling wastes spread from oil fields, and leaks sprung from tanks and pipelines.

Hazardous materials also have an animal way of moving in the environment. The sneaky way they move is up the food chain. As a rule, evolution and good sense keep a species from consuming too much acutely poisonous food.

Yet nature’s linked food system – a long chain of plant-eaters and meat-eaters – can bring harmful substances in slow steps to crowds of unsuspecting people. Worse yet, the process has a nasty trait of accumulating, or magnifying, the bad stuff as it progresses upwards to the top of the food chain. That’s us, mates. The plot is sinister. 

The eaten ones pass their all, good parts and bad, on to their eaters. The eater burns the good stuff to get energy. The bad things chiefly build up in the eater’s fatty tissue, awaiting the next higher predator. This dark story might be dubbed, “The Prey’s Last Revenge.”

Efforts to keep air, water, land and food suitably safe are attacked on all fronts. On one side, some argue “Toxic stuff is natural. Don’t worry about it.” Other sides proclaim, “We can’t be safe unless all toxic materials are gone.”        

The ways that toxics move in nature emerge but slowly. The knowledge shapes our laws, slowly.