Salon.com > Ian Sample

Plastic’s harmful side effects

Fri, 27 May 2005 13:54:00 +0000

Scientists in America have found the first evidence that common chemicals used in products as diverse as cosmetics, toys, plastic wrap and plastic bags may harm the development of unborn baby boys. Researchers have long known that high levels of substances called phthalates have gender-bending effects on male animals, making them more feminine and leading to poor sperm quality and infertility. The new study suggests that even normal levels of phthalates, which are ubiquitous, can disrupt the development of male babies' reproductive organs.

The discovery poses a huge problem for the chemical industry, which is already embroiled in a battle with the government over the European Union's proposals on chemical safety.

Several types of phthalates, which are used to make plastics more pliable, and have been around for more than 50 years, have been banned, but many are still produced in vast quantities.

Extending fertility

Thu, 05 May 2005 14:28:00 +0000

Scientists have used stem cells to grow healthy human eggs for the first time, a development they believe will usher in new fertility treatments and enable women to delay menopause by a decade. A shortage of donors means fertility clinics desperately need new sources of eggs to help women trying for babies through in vitro fertilization. The research suggests that a nearly limitless supply of eggs could be produced by taking a woman's own stem cells and growing them into eggs in the lab.

Professor Antonin Bukovsky, a researcher at the University of Tennessee in Knoxville, who led the work, says the findings show that women are capable of producing new eggs later in life, rather than being limited to the quota they are born with. At birth, a female's ovaries typically contain around 2 million egg-producing follicles, falling to around 400 by the time she reaches puberty. The number continues to fall until menopause, when too few exist for her to become pregnant.

According to Bukovsky, his work could lead to advances in fertility treatment that would allow women to grow and store their own viable eggs, and delay having a family until an older age. The stem cells could also be used to rejuvenate aging ovaries, with the potential of delaying menopause for 10 to 12 years.

“I just want to be able to scratch my nose”

Thu, 31 Mar 2005 16:17:00 +0000

There's a hand lying on the blanket on Matt Nagle's desk and he's staring at it intently, thinking "Close, close," as the scientists gathered around him look on. To their delight, the hand twitches and its outstretched fingers close around the open palm, clenching to a fist. In that moment, Nagle made history. Paralyzed from the neck down after a vicious knife attack four years ago, he is the first person to have controlled an artificial limb using a device implanted into his brain.

The experiment took place a few months ago as part of a broader trial into what are known in the business as brain-computer interfaces. Although it is early days, aficionados of the technology see a world where brain implants return ability to those with disability, allowing them to control all manner of devices by thought alone. There are huge hurdles ahead. No one knows how much information we can usefully decipher from the electrical fizz of the brain's 100 billion neurons. More important, scientists are still in the dark as to what effect, if any, long-term implants will have on the human brain, or how its circuitry will cope with the new tasks demanded of it.

Long live couch potatoes!

Tue, 11 Jan 2005 15:16:00 +0000

As gyms swell with the optimism of countless New Year's resolutions, a message arrives from Germany that will doubtless bring cheer to sloths. What is the key to a long and healthy life? Laziness. Put forward in the book "The Joy of Laziness -- How to Slow Down and Live Longer," the message has raised eyebrows among experts studying the science of aging. At best, they say, the book is a muddled collection of grains of truth that oversimplify what scientists understand about the complex process of aging. At worst it is dangerous, giving those already living life in the bus lane a handy justification to do little to keep themselves healthy.

"The Joy of Laziness" was written by a German father and daughter team. Peter Axt, say the publishers, is a former health sciences expert at Fulda University near Frankfurt, and Michaela Axt-Gadermann is a practicing dermatologist. The book begins with an explanation that we are all born with a limited amount of "life energy." If we use it all up quickly -- by exercising and getting stressed out -- we will die early. If we do very little and live life at a snail's pace, we can eke it out and live much longer.

The point of pleasure

Fri, 17 Dec 2004 15:32:00 +0000

For as long as they have existed, students have embraced the role of obliging guinea pigs, on hand to take part in all manner of intrusive, humiliating and bizarre experiments dreamed up by their supervisors. Nonetheless, one of Michel Cabanac's experiments must have raised eyebrows. "I offered them money to feel pain," says the physiologist at Laval University in Quebec. "It can be quite dangerous because, what if a student has just destroyed his parents' car? He's going to need money really badly."

Undeterred, Cabanac lined his students up against a wall. It was going to be bad, but not as bad as they might have thought. He got them to sit as if perched on an imaginary stool, a position that forced their weight onto their knees. "Try it," he said. "The pain soon becomes unsufferable." Cabanac then promised the students increasingly large lumps of cash to endure the pain. The more he offered, the longer they suffered. The longest lasted for eight minutes 20 seconds.

Ironically, Cabanac's experiment was part of a broader investigation into the science of pleasure. His aim was to find out what, if anything, was the point of pleasure. His conclusions, and those of other scientists working in the field, suggest that not only is pleasure good for our health, but it is at the root of our ability to make sense of the complex world in which we live.

The Earth’s most fragile places

Thu, 14 Oct 2004 14:31:00 +0000

Cast an eye over the many forests' worth of scientific literature on global warming and it quickly becomes clear that working out what a temperature rise of a few degrees will mean for life anywhere on the planet is far from straightforward. Vast ice sheets may melt, sea levels will rise, and faced with a new climate, species must adapt, move or perish. Yet the precise details of how any of it will happen are, frankly, unknown.

Now it seems the future has become even more uncertain. Climate scientists say they have identified a dozen weak links around the world, regions where global warming could bring about the sudden, catastrophic collapse of vital ecosystems. The consequences will be felt far and wide. An abrupt halt in one ocean current could devastate Antarctic fish stocks, while disruption to another could make temperatures in Britain and elsewhere plunge. When rains return to the Sahara, disease and crop damage from pests could soar. Meanwhile, a drier Amazon will trigger huge dieback of the forests, threatening many species with extinction. Losing the forests will itself exacerbate global warming.

Wired awake

Thu, 29 Jul 2004 13:50:00 +0000

On April 17 2002, an incident just outside Kandahar in Afghanistan thrust one of the military's least favourite subjects into the media spotlight. Two US F-16 pilots, Major Harry Schmidt and Major William Umbach mistakenly bombed a Canadian infantry unit, killing four and injuring eight. But while the "friendly fire" incident was terrible in itself, worse was to come for the military. In the ensuing legal case, it was claimed that the pilots had been pressured into taking amphetamines -- speed -- to sharpen their senses.

The authorised use of drugs by military forces is rarely acknowledged by officials, but despite accidents like the one in Afghanistan, interest in using drugs to improve performance remains high. Yet as money is directed into the hunt for newer and better pills to squeeze more out of exhausted troops, some military researchers believe it's time to quit the drugs and try something radically different.