Monday, June 30, 2008

Carbon Nanotubes and Cancer: A Hazard Forestalled?

Writing about engineering ethics can be a grim business: plane crashes, fires, explosions, or insidious deaths from apparently innocuous things that people did decades earlier show up with depressing regularity in this column. So I try to look for good news every now and then, and a few weeks ago some showed up in the New York Times, of all places.
The good news is not unmixed with bad news, but hey, I'll take what I can get.

The bad news is that it looks like carbon nanotubes—those tiny rods of carbon atoms arranged on a hexagonal grid like chicken wire—may have the potential to cause cancer under certain special conditions. The good news is, we know about the problem long before any epidemiological evidence has shown up that people have actually been harmed in this way.
This looks like a success story of how research dollars spent on engineering-ethics-related matters have actually paid off with some useful information. But first, let me describe carbon nanotubes and summarize the results of the research.

Starting in the early 1990s, many scientists began to be aware that under certain conditions, carbon forms long, thin tubes that can be less than a billionth of a meter in diameter but thousands of times longer than that. The term "nanotube" was invented to describe these structures, and since then there has been a race of sorts both on the scientific and engineering fronts to exploit their fascinating properties. One peculiarity they show is that they conduct electricity extremely well along the axis of the tube, so well that I understand one prominent commercial application is in carbon motor brushes. Anybody who uses a power-line-powered electric drill has used carbon brushes—sometimes you can see sparks from them toward the back of the drill. The purpose of the brush is to conduct current to the armature (the moving part) of the motor. Brushes made with properly aligned nanotubes are more efficient at this than the regular kind, although their added cost doesn't justify using them in consumer products such as drills. But in heavy industrial applications where the brushes may conduct hundreds of amps, they make enough difference to sell.

Anyway, some researchers in the United Kingdom and the U. S. got some government funding to see whether carbon nanotubes might be dangerous to health. One reason to suspect this might be the case has to do with the shape of the nanotubes: long and thin. It turns out that one of the main reasons asbestos particles can cause an otherwise rare form of lung cancer called mesothelioma appears to be that they, too, are long and thin (that's why asbestos is a mineral fiber that can be woven into sheets). Although the connection between the shape of asbestos fibers and this type of cancer is not entirely clear, there is abundant evidence that associates exposure to asbestos with mesothelioma. So the researchers thought it would be worth looking into to see if carbon nanotubes could cause precancerous lesions in mice.

Well, they do. The experiment wasn't continued to the point that the mice actually developed cancer, but they did get inflammation and certain lesions associated with precancerous conditions.

The first thing that will happen is, the researchers will apply for more funding to look into the question further. That seems reasonable, because it's a long stretch from precancerous lesions in mice to actual cancer in humans. The next thing that ought to happen is that people should use appropriate precautions when dealing with carbon nanotubes. What would "appropriate precautions" amount to?

Well, nothing like an outright ban, for example. We have learned how to deal with all kinds of hazardous substances over time, and carbon nanotubes don't seem to be nearly as hazardous as some other kinds of stuff you have around the house—drain cleaner or bleach, for example. If you can keep people from breathing or swallowing carbon nanotubes, the things should be perfectly safe to use otherwise. This may present a problem if someone wants to weave them into clothing, for example, but most of the interesting applications have nothing to do with textiles.

On the other hand, having been forewarned by at least one forward-looking study, we shouldn't totally ignore the potential health hazards that carbon nanotubes might present in the future. All too often, the typical way that health hazards of newly introduced substances have been discovered is that people simply start selling products with the new stuff in them, and months or years later, some weird rare malady starts showing up in a few people (or sometimes not so few). And it takes a lot of epidemiologists doing a lot of Sherlock Holmesing to find the cause. By the time they do, whole industries dependent on the substance in question may have large vested interests in the status quo, and so you get a big political tussle as well as delays in appropriate regulations, if they are enacted at all.

This happened with asbestos and, above all, tobacco, and I hope it doesn't happen with carbon nanotubes. Fortunately, it looks like you can't smoke them, so we probably have less to worry about than with cigarettes. Nevertheless, I hope this study doesn't just disappear and fail to stimulate more research into the possible health hazards of carbon nanotubes. This time, maybe, we can get it right.

Sources: The New York Times article on the possible health risks of carbon nanotubes appeared on May 21, 2008, and can be viewed at http://www.nytimes.com/2008/05/21/science/21nano.html. The research was published in Nature Nanotechnology, and an abstract is available without charge at http://www.nature.com/nnano/journal/vaop/ncurrent/abs/nnano.2008.111.html.

Saturday, June 21, 2008

Does The Internet Flatten Your Mind?

If you are reading this, you must spend at least some time on the Internet, and possibly many hours a day. If you're older than 30 or so, you can remember a time before the Internet when "reading" and "holding a piece of paper in your hands" were generally synonymous. And if you're younger than that, believe me, there was such a time and people actually managed to live under such conditions.

The question for today is: does using the Internet make us less able to do certain important mental feats that we may miss after they're gone? More specifically, does it take from us the ability to give sustained attention to a long, complex piece of reading that requires deep thought?

I am moved to this inquiry by a couple of things. In a recent column, Miami Herald columnist Leonard Pitts Jr. says "amen" to an article in the latest issue of the Atlantic Monthly entitled "Is Google Making Us Stupid?" In the Atlantic article, author Nicholas Carr argues that people who use the Internet routinely tend to zip from info-nugget to ad to email to YouTube to . . . well, you get the idea, all without thinking thoughts any deeper than a puddle on a sidewalk. Both he and Pitts find that since adapting to the Internet, they find it much harder to sit still with a book that makes a complex, sustained argument over many chapters. They end up getting restless or sleepy. And they wonder if the instant-gratification style of thinking that Google and the rest of the Internet services encourage, militates against the deep, contemplative, often temporarily aimless and associative, but sometimes very productive type of thinking that reading at length encourages.

There is some quantitative evidence that this suspicion is true. Carr cites a study that found most Internet users do not read more than a few paragraphs of any resource they find, even if it is many pages long. In the technology and society journal The New Atlantis, Christine Rosen cites numerous studies that show the kind of work style known as multitasking actually decreases efficiency rather than otherwise. And the Internet makes multitasking so easy—just open three or four windows on your email, a favorite blog, a video news feed, and go to it.

I must admit that the Internet has profoundly changed the way I do what I used to call library research. My professional research is eclectic in that I often find myself working in fields that I do not have much educational background in. Suppose (as recently happened) that I want to find out about an arcane subject such as astronomical spectrophotometry. (For those who just have to know, it means measuring the light output of stars at various wavelengths.) In the pre-Internet days, this would have meant a trip to the library (preferably the multi-million-volume University of Texas library system), perhaps talking with a reference librarian, hauling six or eight books to a study carrel, writing down references to papers, going back to the shelves and looking up the papers in big heavy volumes of bound journals, and so on. It would have taken a whole day if done properly, and I might have ended up with two or three photocopied papers, some notes, and a whole lot more questions than answers.

Contrast that to what I managed to do yesterday. I Googled the topic, found a few papers online, got more confused than anything else, and ended up going to the library anyway (the local Texas State library, not Austin). I found two books that addressed the subject, but from an insider's point of view. Fortunately, one of them listed some references for introductory works—most of them were books, but one was an online source. Turns out that a professor at Oklahoma University has written an introductory text that he posts online for free. It turned out to be exactly what I needed.

That's a fairly typical story for any of my ventures into new fields. The online stuff helps some (especially Wikipedia, which seems to have very good articles about the basics of technical topics). But at some point I usually end up going to books, sometimes old books. It's unusual that I can find everything I need to know online, especially if I want an overall picture of a field as an introduction.

Now Google and company are working hard to change that by putting all the world's books online. And yes, they may succeed. But once that happens, somehow I don't think people will write new books the same way they used to write old books. Why put a 300-page book on line if nobody reads past the first three or four pages anyway?

It takes a certain kind of personality to write a good book. A psychological test called the Myers-Briggs Type Indicator alleges to measure a dichotomy between two distinct lifestyles which are termed "judging" versus "perceiving." One author summarized the difference between the two poles of the dichotomy this way. People who rate high on the "judging" end of the scale are "job-oriented jumpers" who like to size up a task, do it, get it out of their way, wipe their hands, and go on to the next thing. Perceiving types, on the other hand, tend to be "pendulous postponers" who can always think of one more touch to add to their creation, or one more aspect of looking at a subject.

Many college professors turn out to be pendulous postponers, delving endlessly into the infinite ramifications of a specialized topic. And since they will stick with a subject longer than anyone else does, they often find things that nobody else has found. The supreme example of this type that I can think of is the cultural historian Jacques Barzun, who turned 100 last November. A few years ago he wrote From Dawn To Decadence, a history of Western culture over the last five centuries, in which he summed up a long lifetime of learning that made connections and associations of ideas that even historical duffers like me could understand.

My mind doesn't work that way. I am a "judging" type, which is one reason I write a blog on a different topic each week, rather than using the same time to write a book or two a year (much as I'd like to write a book!). But the world needs both kinds of thinkers. It's pretty clear that the Internet encourages the superficial, the list-of-numbers kind of judging thinking, over the long-term study, contemplation, pondering, and sustained attention needed for the perceiving kind of thinking. It would be tragic if the Internet wipes out any future hope of having more of the Jacques Barzun type of personality arise in the intellectual world of the future. As long as we don't get doctrinaire about banning books in favor of the Internet or something, I don't think we have much to worry about. But the same end may be achieved by other means, and possibly even by accident rather than design.

Sources: The Atlantic Monthly article appears at http://www.theatlantic.com/doc/200807/google. Christine Rosen's article "The Myth of Multitasking" appears in the Spring 2008 issue of The New Atlantis.

Monday, June 16, 2008

The Micro- and Macro-Ethics of Plug-in Hybrids

The online version of Wired Magazine carried an article recently that took a dim view of the Bush Administration's commitment of $30 million toward plug-in hybrid vehicle research, saying it was grossly inadequate in view of our present oil-price exigencies. A plug-in hybrid car is like a conventional hybrid (e. g. the Toyota Prius) in that it has both batteries to run the electric motor coupled to the wheels, and an internal combustion engine to supplement power from the batteries when necessary. But in addition, a plug-in hybrid can be plugged in to your house current overnight to draw power from the electric grid. If the batteries are large enough, some people claim that plug-in hybrids can travel up to 100 miles per gallon of gasoline consumed, although this doesn't count what it does to your electric bill.

Sounds great, doesn't it? Let's look at the decision to go with a plug-in hybrid from two points of view. First, there's what ethicists call the micro-ethical view: what should you as an individual do about the situation? Then, there is the macro-ethical view: what should large institutions—corporations, professional societies, governments, nations—do about it? As we will see, the answers aren't necessarily the same.

What an individual should do depends on what kind of individual you are. If you're just an average consumer, the choice is simply, "Should I buy a plug-in hybrid or not?" Of course, this assumes that they are out there to buy. And they aren't—not just yet, anyway, although the much-hyped Chevrolet Volt is supposed to make it to showroom floors by 2010. This shows the limitations of microethical reasoning: options are limited to what one person can realistically do.

If you are an engineer, and you think a plug-in hybrid is a good idea, you might try getting a job related to power electronics or automotive R&D. Or you could even start your own company to address one of the many technical problems that lie in the way of plug-in hybrid development. The most promising type of battery, the lithium-ion cell, still has lots of problems with safety and lifetime, although these may be ironed out with time. So one's career choice is fraught with ethical implications that many young people don't even consider to start with, let alone after one has taken the job.

When we turn to the macroethical side of the question, a whole array of sub-questions arise. If a company goes into a market not because it's profitable but because it is the morally right thing to do, that company either has to subsidize its activity by drawing funds from other more profitable lines, or face the prospect of going broke, after which the company will no longer exist to do anything at all, moral or otherwise. There are specialty firms right now that will convert conventional cars to plug-in hybrids, but my impression is they are not growing fast and simply don't have the resources to compete with the major automakers. The automotive industry is a strange mixture of century-old traditions (the way car dealership economics works, for instance) and cutting-edge technology. Any organization that wants to succeed in it has to work within the complex environment of existing companies, regulations, and market forces.

The problem is even more complex when you ask what the U. S. government might best be doing in this area. Obviously, the Wired reporter (as well as several private and public sources he quoted) thought that $30 million was so small an amount as to be an empty gesture. He quoted a source at the Brookings Institution who said that to make a major impact on the auto market, plug-in hybrids would need about $18 billion of government subsidies and funds over the next ten years. That is a lot, but compared to many other things the government does, it's not all that much.

Over against that notion is the sense, supported by many conservative schools of economics, that we will have plug-in hybrids when fuel costs and other economic factors make it profitable to sell them, and any government intervention to hasten that day is liable to be counterproductive. Macroethics in engineering gets tangled up in economics and public policy pretty quickly, as you can see.

My own opinion of the matter is that there are technical solutions out there, but those who have the nominal power to implement them (both in private corporations and in government) lack the courage to go ahead and do something. The "something" might be in a variety of directions, either liberal or conservative. But my sense is that lately, no one has been willing to step up and put their hands on the wheel and steer. And just as with an individual who drifts through life reacting to things without making or implementing specific plans, institutional drift is sooner or later bound to lead to disaster.

As far as buying a plug-in hybrid goes, I plan to hang on to my own two cars for a while yet. One of them has 183,000 miles on it and the other, which already gets about 37 miles a gallon, is about to turn over 100,000 miles. The car I had before that made it to 200,000 before the wheels began to fall off (literally). So I figure by the time I'm in the market for another car, one of my choices is likely to be a plug-in hybrid. But whether I'll be able to afford it is another question.

Sources: The Wired article on plug-in hybrids appeared on June 13, 2008 at http://blog.wired.com/cars/2008/06/feds-scrape-tog.html.

Monday, June 09, 2008

New York's Crane Collapses: Who Inspects the Inspectors?

New York City is undergoing something of a building boom, and building in large cities means tower cranes—those improbably spindly structures that symbolize major construction these days. Last May 30, a crane in use at 91st Street in Manhattan collapsed, killing the operator and another construction worker, seriously injuring a third, and damaging several buildings as it fell to the street below. What made it even worse is that this collapse was the second in less than three months. On March 15, another crane collapsed in midtown Manhattan, killing seven. And in both cases, it appears that the inspection process designed to prevent just such accidents was flawed, to say the least.

What do crane inspectors do? What pressures do they experience in their jobs? And what changes can be made in the system to improve it?

On paper, at least, New York City appears to have a rigorous and exacting system of required inspections for the erection and use of tower cranes. Every contractor has to have a permit to operate a crane, the operators themselves must be licensed by passing tests or showing an equivalent amount of specialized experience, and the cranes themselves must be inspected periodically by crane inspectors, who are city employees. And most of the time, the cranes operate without major accidents or injuries. But it looks like all is not as it should be with the inspection process.

In the March accident, a crane inspector was arrested under the suspicion that he falsified a statement saying he inspected the crane on March 4 that later collapsed. And just last Friday, the acting chief inspector of cranes, James Delayo, was arrested on charges that he took bribes to supply a construction firm with answers to the crane operator's test, as well as to report inspections on cranes that he never in fact inspected. But even if all the inspectors involved had done their jobs, it appears that the May collapse might not have been prevented. A New York Times reporter found that the collapsed crane's turntable was a rebuilt unit that had earlier been struck by lightning and welded back together. It is entirely possible that a hidden defect in the weld contributed to the accident, although further investigations will have to be conducted to confirm that theory. If so, a routine visual inspection might not have revealed any problem.

Inspectors, quality control engineers, traffic policemen—the job of all these people is to make sure that what is supposed to happen actually happens, and what isn't supposed to happen, doesn't. And if they see problems, or potential problems, they have the authority to act. Any time a person holds authority over others, there is the temptation to abuse that authority. And it is no news that from time to time, inspectors take bribes instead of doing the harder thing—actually making the inspection or penalizing a crane operator for careless actions.

A chronic problem with government-operated departments of inspection—whether the things inspected are cranes, X-ray machines in dentists' offices, or sides of beef—is a shortage of inspectors. The benefits of inspection are largely invisible, while the negative consequences of inadequate inspection are blatted all over the news media. The political tendency is therefore to fund inspection agencies just enough to prevent too-frequent accidents, but not so much that the inspected industries and businesses get sore from being plagued with swarms of supernumerary inspectors. The technical abilities required of an inspector can be equal to or greater than his or her counterpart in private enterprise, but government pay is always less than in the private sector, adding to the temptation to bribery.

Some states have decided to outsource certain kinds of inspection to private third-party firms. This leaves the free market to decide the pay rates and numbers of inspectors, but has its own problems as well. How do you insure that a private inspection firm, which is basically a kind of consulting operation, is doing its job? Hire government inspectors to inspect the inspectors? Whether an inspector works for a public or private firm, the issue always comes down to professional integrity: does the inspector know enough technically to do a good inspection? And if so, do they have the moral fiber to resist the temptations to bribery, shortcuts, and other forms of professional corruption?

In today's short-term bottom-line world, the kind of long-term relationships and institutional reputations needed for inspection systems to work well can be hard to establish. But it is too easy to forget that lives are at stake. New York City appears to be trying a short-term fix by prosecuting some crane inspectors who were alleged to be on the take. While that is certainly something that needs to be done, one wonders whether corruption in the process may be endemic, and the arrests happened only in response to headlines. Is privatization a better approach? Maybe, but as in so many other aspects of engineering, you have to work with the materials, culture, and political environment you have, and privatization in certain political circles is a dirty word. Here's hoping that however it gets done, the system of crane inspections in New York improves to the point that seeing those giant towers swinging across the skyline will be only a source of pride, and not of fear.

Sources: I used reports from the New York Times on the crane accidents and bribery arrests available at http://www.nytimes.com/2008/06/07/nyregion/07crane.html and http://www.nytimes.com/2008/06/08/nyregion/08building.html. A technical description of the March 15 collapse is available at http://www.gostructural.com/article.asp?id=2788.