May 29, 1998

India's nuclear tests raise environmental fears

In the aftermath of India's surprise nuclear weapons tests this month, environmentalists are scrambling to assess the damage. What short-term and long-term environmental impacts are we talking about? And why do governments continue to test?

"It is easy to obtain the parts to build a nuclear bomb," says Dr. Nathan Rodning, associate professor of physics. What's harder, is seeing if the parts you've assembled will work. "Refining uranium to create plutonium, although expensive, is not as difficult as is assembling the electronics."

"Complex electronics and geometry require an enormous amount of technical expertise," says Rodning. "...Countries with nuclear reactors often have the raw materials, but lack the technology to put it all together. Successful testing not only means the mechanism was built properly but it also symbolizes an advanced technical literacy -- "Look, take us seriously."

By while the tests may prove a political point, they will harm the environment, he says. The detonation of an underground nuclear device results in the emission of two of the most radioactive elements that exists: Strontium-90 and Caesium-137, along with other damaging elements.

These elements can seep into the groundwater and have the potential to be released into the atmosphere. Rodning says researchers claim underground testing will not have a profound impact on the atmosphere or the soil. They claim any radiation produced by the explosion is contained in a "glassified substructure" -- melted rock as a result of the explosion.

"I'm particularly skeptical about this because we have no idea how long the radionuclides [radioactive elements] can be sealed," says Rodning. "It is impossible for leaks not to occur."

In order for scientists to obtain data, they must drill holes into the site thereby exposing the core allowing elements to leak into the atmosphere and local aquifers. There is no way to measure how much radiation can leak when holes are drilled. In addition, natural shifts in the earth's crust heighten the possibility of leaks.

Rodning is also worried about the decaying of Strontium-90 and Ceasium-137. These elements have a half-life of 30 years. That means their intensity will remain at full capacity for 30 years, at which point, their intensity decreases by half. However, new evidence shows some radioactive elements increase in intensity once they begin to decay.

A worse threat, is that the plutonium in nuclear bombs "is the most poisonous biological material known to man and has a half-life of 24,100 years," says Rodning. In other words, it won't go away.

If the bomb itself was not enough, a process called "salting" can be used to magnify its devastating effects. In salting, layers of chemicals are added merely to increase the fallout capacity, a layer of tritium can be added to increase the power of the bomb. Rodning says there is no way for us to know whether the Indian government has conducted this type of test, but it is known that they have the ability to do so.

What's most frightening is what's unknown -- the impact on the soil, the atmosphere, flora, fauna, and of course on humans. The extent of the damage is difficult to predict, however, we know the effects of other tests and can suspect the same types of damage.

If radioactive elements have seeped to a nearby aquifer, it might show up in water sources next week or in 20 years, says Rodning. And if we do find plutonium leaking into the water system, there is neither a cure nor a treatment for the contamination. Human exposure to plutonium results in leukemias, other cancers and other radiation-related diseases.

"The land is a write-off forever, especially if scientists are uncertain about leakage," he says.

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