How Orange Rinds Help Save the Ozone

THE throwaway part of your breakfast juice is helping to reduce a serious environmental threat - the widening gap in the ozone shield over the Antarctic. A substance made from orange and grapefruit rinds is replacing the harmful chlorofluorocarbons (CFCs) in a new solvent. William Galloway, of Fernandina Beach, Fla., says depletion of the protective ozone shield surrounding the earth by the use of CFCs ``is a much more serious problem than most scientists are saying publicly.'' So six years ago, in collaboration with AT&T, he set his PetroFerm research company to tackle the problem.

Numerous environmentally benign products, including metal cleaners, an optical lens cleaner, and a substance used in asphalt extraction have emerged from the company's research laboratories in recent years. Now comes BioAct EC7, a solvent based on terpenes that are extracted principally from citrus waste but also from pine bark and other organic materials.

BioAct EC7 can substitute for the CFC used as a cleaning agent in electronics manufacturing.

While the public is primarily aware of CFC as the now-banned (in several countries) propellant in aerosol cans, it remains a commonplace, highly evaporative cleanser, accounting for some 17 percent of its total use worldwide, according to Worldwatch Institute figures. Refrigeration/air conditioning (35 percent) and foam packaging and insulation (25 percent) are the leading users.

In particular, CFCs are used to wash printed wiring assemblies (PWAs) in radios, computers, guidance systems, and a host of other electronic gadgetry.

PWAs are the cards that computer chips are fastened to. They are circuit boards, or, in other words, ``the parts that do the thinking,'' as Craig Hood, marketing manager for PetroFerm, describes them.

For this reason the boards must be spotless. A speck of dirt or flux in the wrong place could result in faulty electronic signals. ``That might not be crucial in your transistor radio, but in the guidance system of a space probe, or on an aircraft, the end result could be disastrous,'' Hood points out.

When a circuit board is cleaned with a chlorofluorocarbon solvent, the fluid on the board is left to evaporate, and therein lies the danger to the environment. the solvent rises as a gas into the atmosphere, where it slowly degrades the ozone shield.

In contrast, BioAct EC7 is a solvent based on terpenes that occur naturally on a wide scale. Biodegradable, they do no harm to the environment. The oils pressed from citrus rinds left over from the juicing process are ``particularly rich in terpenes,'' says Hood. This makes the product a natural for Florida.

AT&T has begun using EC7 because the product ``outperforms CFC solvents and is already cost competitive,'' Hood says. The news, he adds, ``is all good.

Under international agreement, CFC production will steadily decrease over the next decade until, it is hoped, it will cease altogether. Meanwhile some Florida citrus rinds are contributing to the process.