ew of us can deny the desirability of lubricants that, in their normal use, come in contact with the environment but do not

harm. Obvious examples are lubricants like chainsaw oils, track-side lubricators for railroads and a number of agricultural equip-ment lubricants. Many is the time I have been to power boat ma-rinas and harbors where I saw an iridescent sheen of oil on the surface of the water—good for keeping the mosquito population down but otherwise not so good for more beneficial species.

Not to worry, of course—all we have to do is just use lubricants that don’t harm the environment, the so-called environmentally

friendly lubricants. As with most complicated issues, as you peel back the onion layers you find life is not so simple.

First, what do we mean by harm? Perhaps we mean the lubri-cant biodegrades naturally and is nontoxic to plants and animals. But how do we know that? By reading the label?

It turns out that there are a number of tests that purport to measure biodegradability. The Paris-based Organization for Eco-nomic Co-operation and Development (OECD) has promoted tests such as one based in ISO 14593 for Inherent biodegradability—the Concawe Test.

But in truth there are no truly standardized tests that actually simulate the real world. Part of the problem is that the real world is not a very standardized place.

First, there is aerobic and/or anaerobic bacterial degradation—which is it? Some things will biodegrade quite rapidly in the Sa-hara desert but will hang around for centuries in the Arctic or Ant-arctic.

Then there is the problem of what actually happens when something “hangs around.” For example, which is worse: some-thing that doesn’t degrade but also is virtually inert or something that degrades but produces side products that are harmful to fish, plants or whatever?

I think I would prefer the something that isn’t very biodegrad-able, like a glass bottle. A bottle is basically silicon dioxide, which is also the same thing as sand. Eventually environmental forces, freezing, thawing, earthquakes, etc., grind the bottle back to sand

You know things are complicated when even the question of whether or not a substance is harmful is difficult to answer.

F

Environmentally friendly lubricants—really?

LUBRICATION FUNDAMENTALSDr. Robert M. Gresham / Contributing Editor

KEy CONCEPTS:

• AmaterialthatbiodegradesrapidlyintheSaharadesertmighthangaround for centuries in the Arctic or Antarctic.

• Makingalubricantlesstoxicoftenmakesitlesseffective—meaningmore of it must be issued into the environment.

• AnSTLE-sponsoredseminarattheAOCSconferencethismonthwillhelp clarify many of these issues.

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anyway. And what about many plastic bottles? Some don’t degrade very fast. They are basically organic polymers that don’t hurt any-thing either—other than serving as eyesores.

Indeed, the problem is a many layered onion.Another problem in addition to biodegradability is what we

mean by nontoxic. Some materials are toxic to one species and food for another. Of course, toxicity also is based on dose and time or frequency of exposure. Pure water is toxic to humans if too much is ingested over a short time.

Then there is the whole panoply of materials that are “sus-pected” of causing one kind of problem or another, like suspected carcinogens. How much suspected? What’s a lot of suspicion? Of course, our political class who pass the regulations cannot even begin to deal with these kinds of issues, because their law degrees and overreaching special interest groups don’t allow them to deal with these problems in a rational way. So they pass laws that use words like “none,” “any” and “all,” etc., because it is too difficult to set limits that are totally risk-free or even reasonably risk-free. And, of course many such laws have loopholes carefully designed to nurture the wants and needs of the legislator’s friends.

What’s a poor lubricant formulator or user to do? EPA lists a number of additive materials that should not be used in lubricants for one real or suspected reason or another. That’s at least helpful, but the problem is that taking these materials off the table results in lubricants that don’t work as well. Result: more oil changes and, thus, a larger pollution load, albeit with presumably less toxic ma-terials. Which is worse, a larger dose of less toxic materials or a smaller dose of more toxic materials? The politicos just say no dose, which is their way of saying—I can’t deal with it! See, it’s easy.

And we have a variety of base oils that are available to use as well. Of course, there is the philosophical problem that base oils are derived from crude oil that comes out of the ground, a naturally occurring, environmentally compatible material. By get-ting rid of impurities and selecting a molecular weight range and configuration that is optimal for lubricants, we still are left with a naturally occurring, environmentally compatible material. And isn’t such a naturally occurring material that already is the result of biodegradation of organic material obviously compatible with the environment?

Well, apparently not. So we look to materials like vegetable oils, which also require refining to reduce impurities and optimize the molecular weight range and configuration. However, these ma-terials biodegrade at varying rates and conditions, and of course those most like minerals oils work the best and those that biode-

grade the most also degrade in the application being lubricated—not good for the multimillion dollar piece of machinery.

Well, there is a light somewhere in this tunnel of gloom and doom. STLE’s Environmentally Friendly Fluids Technical Committee, chaired by Dr. Sevim Erhan, has a technical session on “Lubricants and Oleochemicals” at the upcoming American Oil Chemists Soci-ety (AOCS) conference, Oct. 13-16 in Cincinnati. AOCS is a global professional scientific society for all individuals and corporations with interest in the fats, oils, surfactants, detergents and related materials fields.

Some of the STLE-member presenters are familiar and welcome faces: Dr. Joe Perez, Penn State University, looks at “Oxidation Studies of Vegetable and Petroleum Base Oils With and Without Additives;” Dr. Fran Lockwood, Ashland Inc./The Valvoline Co., dis-cusses “Formulating and Testing of Engine Oils with Bio-content;” and Lubrizol’s Dr. Rob Profilet examines “Environmentally Friendly Hydraulic Fluids,” just to name a few.

This can be a good partnership for STLE as the issues described above are of critical interest to us all as we try to sort out this whole problem of just what an environmentally friendly lubricant actually is. Check out this important industry event at: www.aocs.org.

Bob Gresham is STLE’s director of professional development. You can reach him at rgresham@stle.org.

Which is worse: something that doesn’t degrade but is virtually inert

or something that degrades but produces harmful side products?

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