Human Nature: Science, Technology, and Life.

Body Parts From Trash

We cover a lot of fancy technology in this blog. But sometimes the most ingenious and far-reaching gadgetry is the least fancy.

A few recent cases: First we looked at incubators made from car parts. Then we learned about ugly standardized glasses you can adjust to your eyesight with a pump. In both cases, engineers are improving life in the developing world by using cheap, available materials instead of cutting-edge technology. But why stop with external devices? Why not extend the low-tech, high-utility revolution into the human body?

That's what Thailand's Prostheses Foundation is doing for thousands of Thais who have lost their legs to land mines, diabetes, and birth defects. "In 17 years, the foundation says it has given away more than 30,000 legs," Agence France Presse reports. In the United States, prosthetic legs cost $10,000 to $50,000 or more. So how can the Prostheses Foundation afford to give them away?

Answer:

It is the recycled materials that make the project workable, Thamrongrat [the foundation's vice chairman] said, as they they keep costs down and allow the foundation to make and distribute more legs. The foundation asks people to donate materials that can be used in the limbs, such as beer cans and aluminum pots. A prosthetic for below the knee costs the foundation 1,000 baht (about 28 dollars) to make, Thamrongrat said. It would cost the government 10,000 baht to build a similar one.

Example:

Twelve-year-old Matoha Dosare was born with no right leg, but thanks to recycled soft drink cans and some old stockings, he now has a new limb and new-found independence. ... Matoha has had three new legs fitted in the last two years, with the metal in the joints coming from the donated bottle caps and tins. The nylon from the stockings is used in the sculpting process to help form the legs.

Three prosthetic legs in two years? That sounds bad. The downside of getting a leg made from soda cans is that aluminum doesn't last as long as steel. But if the upside is a 90 percent cut in production cost, the kid comes out ahead, because he can get those three legs for one-third the cost of a government-issued prosthesis. And since he's growing, each new leg can be adjusted to his increasing size.

But here's the really interesting twist:

One prosthetic offered is the "farmer's leg," which uses more steel and ends in a stump with tire treads on the bottom rather than a false foot. This was created because farmers complained the foot got stuck in the mud. ...

The prosthetic extension designed to mimic a human foot did what feet sometimes do: It got stuck. So the leg makers replaced it with an extension designed for performance in mud. They made a foot more like a tire. In fact, they made a foot from a tire. It lacks the mobility of a healthy human foot. But for farming in Thailand, it has a better shape.

Adjustable Glasses

Last month, we talked about the transition from George W. Bush to Barack Obama and what it might signify for biotech policy: a shift from a conservative interest in technological frontiers to a progressive interest in distributive justice. Less debate, for instance, about things like future artificial wombs, and more attention to things like incubators made from car parts. The point of car-parts incubators was that nobody cares about the latest million-dollar American baby born at 21 weeks when you live in a country where preemies die at 35 weeks. What most of the world needs is an affordable incubator that works for most preemies and can be reliably maintained.

Here's another target for the progressive ethic: eyeglasses. The man leading the charge is Joshua Silver, a physicist at Oxford. In Saturday's Washington Post, Mary Jordan explains the situation:

In the United States, Britain and other wealthy nations, 60 to 70 percent of people wear corrective glasses, Silver said. But in many developing countries, only about 5 percent have glasses because so many people, especially those in rural areas, have little or no access to eye-care professionals. Even if they could visit an eye doctor, the cost of glasses can be more than a month's wages. This means that many schoolchildren cannot see the blackboard, bus drivers can't see clearly and others can no longer fish, teach or do other jobs because of failing vision.

Silver's answer: Adjustable glasses.

[T]he more liquid pumped into a thin sac in the plastic lenses, the stronger the correction. Silver has attached plastic syringes filled with silicone oil on each bow of the glasses; the wearer adds or subtracts the clear liquid with a little dial on the pump until the focus is right. After that adjustment, the syringes are removed and the "adaptive glasses" are ready to go. Currently, Silver said, a pair costs about $19, but his hope is to cut that to a few dollars.

Silver has already distributed some 30,000 pairs, chiefly through the U.S. Department of Defense, which is giving away 20,000 (with U.S. public-relations inscriptions attached) in Africa and Eastern Europe. His next goal is to disseminate another million pairs in India. The ultimate target is 1 billion people who need glasses but don't have them.

Silver's glasses are ugly. They don't correct astigmatism or catch glaucoma. They're inferior to what the eye-care industry can sell you. But they're superior to what most people in need of vision correction can buy, which is nothing. I'm a congenital critic of utilitarianism (the idea of promoting the greatest welfare of the greatest number of people) when it threatens humanity. But when it serves us -- all of us -- I'm a big fan.

If you like Silver's vision, here's his Web site. Take a good look.

Incubators From Car Parts

Hey, Detroit! We have a new job for you.

Just in time to bail out the auto parts suppliers, Madeline Drexler heralds the latest cool new (or is it old?) idea: car-parts incubators. Here's her description of them in yesterday's Science Times:

The heat source is a pair of headlights. A car door alarm signals emergencies. An auto air filter and fan provide climate control. ... Unlike the notoriously high-maintenance incubators found in neonatal intensive care units in the United States, it is easily repaired, because all of its operational parts come from cars. And while incubators can cost $40,000 or more, this one can be built for less than $1,000. The creators of the car parts incubator ... say it could prevent millions of newborn deaths in the developing world.

We're so used to incubators these days that we've forgotten how radical they are. Their function, Drexler notes, is "providing a warm, clean, womblike environment in which a baby can mature." In short, they're artificial wombs. They don't replicate every function, of course. But for millions of babies who would otherwise die, they replicate enough.

They also destabilize our notions of abortion and infanticide. U.S. abortion laws are organized around viability, the idea that a fetus is entitled to protection when it can survive outside the womb. That's a technical question, and incubators, by creating a kind of womb outside the womb, influence the answer. The earlier they can sustain preemies, the further the line of viability advances.

But that's the fancy far edge of incubator technology. Drexler is talking about something simpler and more immediate: making basic incubation available and functional around the world. Who cares about the latest million-dollar American baby born at 21 weeks when you live in a country where preemies die at 35 weeks? You can't spend that kind of money. You can't even find somebody local to fix a $20,000 incubator. You need an affordable machine that works for most preemies and can be reliably maintained. That's what the car-parts incubator is designed for: babies born at 32 weeks or later.

In the transition from George W. Bush to Barack Obama, we're going to see a big shift in the politics of biotechnology. The conservative preoccupation with technological frontiers will be replaced, for the time being, by a progressive preoccupation with distributive justice. That means less debate about things like future artificial wombs and more attention to things like car-parts incubators. In some ways, it'll be more boring. But tell that to the woman in Indonesia who gets to keep her baby.