COLUMBUS -- When the Industrial Revolution changed the nature of life in America for the better, it also brought with it environmental pollution. Heavy metals tainting the nation's ground-water supplies are part of that legacy.

Now an Ohio State University plant biologist is devising ways to stop that contamination before it reaches the ground water. His answer: algae.

Richard T. Sayre, chair of the Department of Plant Biology, is working with a species of metal-grabbing algae, Chlamydomonas reinhardtii, that acts like a sponge to soak up and bind a variety of heavy metals, including copper, in the soil before it gets to the ground water.

"I became interested in this problem about five years ago," Sayre said. "Genetic engineering was just becoming possible for this kind of algae, and I wanted to see what we could do to increase its metal-binding properties."

Heavy metals enter Lake Erie through four rivers: the Cuyahoga, Black, Maumee and Ashtabula. Sayre's research offers the promise of safer, more effective and relatively inexpensive cleanup of these heavy metals.

While small amounts of some heavy metals, including zinc, copper and nickel, are necessary for human health, others, like cadmium, chromium, mercury, lead and uranium, are not, Sayer said. Therefore, prolonged exposure, even at a low dosage, or a more concentrated short-term exposure, is cause for concern.

Ohio has every heavy metal you can name: lead, cadmium, chromium, mercury, nickel, copper, zinc and uranium.

In fact, Ohio ranks in the top 10 states in the nation for unacceptable levels of heavy metals. Ohio ranks third among all 50 states in mercury levels and second in copper release. Every year, 336,480 pounds of copper are discharged into the environment.

This is where Sayre's algae can come to the rescue.

"Algae can be changed genetically to bind about 20 percent of their total weight. Once the metal binds to the algae, the algae can be harvested and the metal recycled, reducing the total amount of metal mined, smelted and released into the environment," Sayre said. "It also could be deposited in safe-site waste dump locations where it is unlikely to cause problems."

This is an excellent example of the good uses of biotechnology, Sayre said.

"There are so many advantages to using algae," he said. "It's renewable. It doesn't require much energy to produce it, and it is non-toxic."

Concern about organic pesticides, such as PCBs and atrazine, sometimes obscures the greater challenge that heavy metals pose, Sayre said. Since these metals cannot be broken down like pesticides, their removal becomes difficult and expensive, restricting the kinds of technologies that can be used, he said.

Currently the global cost for heavy-metal cleanup and prevention is $30 billion a year. It's been estimated that the bioremediation market in the United States alone will be $300 million by 2005.

###

(ST/LO)