Lawyers for Clarence Hill, a 47-year-old Florida prisoner sentenced to death for killing a police officer, had argued that immense pain in a prisoner's dying moments caused by the drugs would violate the U.S. Constitution's ban on "cruel and unusual punishment."

The Supreme Court has not ruled on the merits of that argument but legal experts say the decision to admit the Hill case means many other last-minute challenges to death sentences can be expected.

Lethal injection used since 1982

When lethal injection was first used in Texas in 1982, it was introduced as the most humane method of execution. It is the main form of execution used by 37 of the 38 American states that have the death penalty. Nebraska uses the electric chair.

Three chemicals are generally used in the procedure - a powerful anaesthetic, a muscle relaxant and a lethal dose of potassium chloride, which disrupts messages between the heart and the brain.

A study published in April 2005 by the British medical journal Lancet found that up to 43 per cent of inmates might still be conscious after receiving the anaesthetic, which would leave them able to feel great pain from the potassium chloride.

Twelve American states have banned potassium chloride injection as too painful for use in the humane killing of pets.

Ruling to have impact, experts say

Deborah Denno, a law professor at Fordham University in New York City, says the Supreme Court ruling will shake up certainties about lethal injection, especially among prison officials who administer the punishment.

"I think they're going to be under much more scrutiny about what they're injecting and it really pushes them to look at other kinds of drugs - or to make sure that their executioners are going to be trained well to do the injection."

In California - which along with Florida and Texas accounts for nearly half of all American death sentences - an execution was halted earlier this year when the only two medical doctors involved in the procedure withdrew their services. Both were anaesthesiologists.

The American Medical Association has advised its members not to take part in executions but some doctors have disregarded that. Most have to work anonymously and are often paid in cash for their services, to avoid public exposure and professional censure.

There are more than 3,100 prisoners awaiting execution in American jails. The number has gone down in recent years along with a decrease in violent crime.

The DNA sequence of smallpox, as well as other potentially dangerous pathogens such as poliovirus and 1918 flu are freely available in online public databases. So to build a virus from scratch, a terrorist would simply order consecutive lengths of DNA along the sequence and glue them together in the correct order. This is beyond the skills and equipment of the kitchen chemist, but could be achieved by a well-funded terrorist with access to a basic lab and PhD-level personnel.

One study estimated that because most people on the planet have no resistance to the extinct virus, an initial release which infected just 10 people would spread to 2.2 million people in 180 days.

The DNA sample we ordered had, at our request, three small modifications to render it harmless before it was sent by post to a residential address in London. The company has since conceded that it was not aware it was sending out a sequence of modified smallpox DNA.

There are legitimate reasons for researchers to buy lengths of DNA from pathogens, for example in developing treatments or vaccines against them. However, because this industry is so new and unregulated, companies are selling custom-made DNA without making thorough checks on the identities of the people who are placing the orders or what the sequences are.

Of the four main companies operating in the UK, none currently screens all their DNA orders. There are 39 companies operating in North America and not all screen their orders.

"This is the most disturbing story I have heard for some time," said Phil Willis MP, chairman of the parliamentary science and technology committee. "There is clearly a massive loophole which needs to be dealt with by regulation or legislation."

Alistair Hay, who is an expert on biological and chemical weapons at the University of Leeds and who advises the government and police, said he was concerned that the company was prepared to supply the DNA to a residential address. "I am surprised that it was so easy," he said.

"I think for any company offering [DNA] sequences there is a need to have some screens in place for sequences that may be suspect," added Prof Hay.

"This is a new field and the regulations haven't really caught up with the technology yet," said Robert Jones at Craic Computing in Seattle, a company that makes software which some DNA synthesis companies use to screen their orders for potentially dangerous sequences.

The potential to manufacture viruses from scratch first came to light in 2002 when US researchers pieced together the genome of the polio virus using short sequences of DNA around 70 letters long. And last year, another team recreated the 1918 flu virus, a devastating and now extinct strain that killed an estimated 50 million people, more people than the first world war.

Building smallpox using the same technique as scientists used to make polio and 1918 influenza would be technically difficult because the virus is larger - the smallpox genome is 185,000 letters long, the influenza genome is 13,500 letters and polio is 7,741 letters. But as techniques improve there is no theoretical reason why it could not be done.

Craig Venter, the US entrepreneur famous for sequencing the human genome, announced in 2003 that his team had constructed the virus phage PhiX174 in two weeks. This has a genome 5,386 letters long. He is currently working on making a bacterium Mycoplasma genitalium from scratch which has a genome around twice as large as smallpox.

The Guardian placed an order online with VH Bio Ltd, a company in Gateshead, Tyne and Wear, that supplies equipment and chemicals used in standard molecular biology labs. We used an invented company name along with just a mobile telephone number and free email address.

VH Bio Ltd rang to check whether the address provided was a residential address. The journalist told VH Bio Ltd that our company was in the process of moving offices and so wanted to make sure the order arrived.

The package, which contained a 78-letter sequence of DNA, which is part of one of the smallpox virus's coat protein genes, was delivered by the Royal Mail to a flat in north London. The A5-sized Jiffy bag contained a small plastic phial with a tiny blob of white gel at the bottom - the DNA. The order cost £33.08, plus an additional £7 for postage.

Alan Volkers, chairman of VH Bio Ltd said the company had no idea that the sequence they produced was a modified sequence of smallpox DNA.

He added that many of its regular customers carry out research which requires supplies of DNA sequences from pathogenic organisms, and his company does not normally screen DNA orders less than 100 letters long. After discovering that it had supplied a small sequence of smallpox DNA, the company carried out checks on two European databases and a 30-minute check using scanning software, but none of them raised any alert.

Dr Volkers added that the company processes several hundred short-sequence orders per day and added: "It would be impossible to run them all through [standard scanning software] and operate successfully."

"There are no regulations in place which require us to carry out background checks on potential customers," he said. "We will, of course, comply with any regulations which are introduced."

Before beginning the investigation, the Guardian obtained advice from four independent scientists, including an international expert on pox viruses, the family to which smallpox belongs. They told us the order would be safe to produce, transport and receive.

Without modifications to the sequence, it could potentially fall foul of the Anti-terrorism, Crime and Security Act 2001. This lists so-called Schedule 5 pathogens and toxins which are illegal to keep or use without first notifying the authorities. Also covered by the act is DNA "associated with the pathogenicity" of the organisms on the same list.

In order to avoid our sequence coming under the act the DNA sequence we ordered had three changes built into it to create so-called "stop codons".

These are effectively full stops in the genetic code which mean that if the sequence were ever put together with others to make a smallpox gene the protein production machinery would stop at that point. So the sequence could never form part of a functional gene.

In making and receiving the order neither we, nor VH Bio Ltd, have broken the law, but the most widely used software (called Blackwatch) for screening DNA orders for potential bioterror agents picked out our sequence as suspicious in a scan run by Craic Computing. This is because it looks for sequences of DNA letters close to sequences from dangerous organisms.

Also known as necrotizing fasciitis, flesh-eating bacteria are potent enough to turn a wound as minor as a pinprick or paper cut into a massive infection causing amputation or even death. In Oklahoma, Adair's death is the latest of about a dozen people who have died from the infection since 2003.

Nationwide, there are about 500 reported cases a year, according to the Centers for Disease Control and Prevention.

The infection is caused by bacteria, usually a type known as Group A Streptococcus (GAS), which thrive naturally on the throat and on the skin.

The good news: Few people in contact with GAS will develop an infection, and it doesn't appear to be very contagious. The bad news: No one yet knows why GAS sometimes becomes invasive.

"These infections are very sporadic and unpredictable, and pop up all the time," said Dr. John Shanley, director of Infectious Disease at the University of Connecticut.

'Changes Right Before Your Eyes'

GAS bacteria can enter the body through cuts, scrapes and even bruises. Sometimes, as in Adair's case, there is no identifiable entry point.

When the bacteria reach the blood, muscles or lungs, they can destroy muscles, fat and skin tissue - hence the term "flesh eating."

"It is very aggressive and changes right before your eyes. It can start as a pimple on the leg and then involve the entire leg in less than a half hour," said Dr. Ferdinando Mirarchi, professor of emergency medicine at Drexel University in Philadelphia.

If left untreated, the infected area begins to swell and appear bluish, white or flaky. Once it has progressed to this point, amputation of the infected area and immediate antibiotic treatment usually are necessary.

As scary as this sounds, most experts agree that there is little that can be done in the way of prevention.

Some People More at Risk

"Just cleaning wounds with soap and water is your best shot, but is probably of little use in general," said Dr. Carl Schultz, professor of emergency medicine at the University of California Irvine.

Any type of abnormally painful inflammation of the skin could signal a possibly serious infection, said Dr. Pascal Imperato, professor and chair of Preventive Medicine and Community Health at the State University of New York.

Therefore, "early diagnosis is essential" to save lives, he said, although as Adair's case shows, this isn't always possible.

Flesh-eating bacterial infections are more common in people with weakened immune systems, diabetics, or intravenous drug users - but healthy people also are vulnerable.

In fact, Mirarchi said "we are seeing an increase in number of cases throughout the years, but to what that is due remains unknown."

Is the Problem Getting Worse?

Since 2003, 10 people in Oklahoma have died from necrotizing fasciitis and the CDC states that approximately 660 infections were attributed to the bacteria in 2003. Deaths weren't available.

CDC officials also say that while cases can pop up in small clusters of people, it is important to remember that they will not spread across the country and that the GAS bacteria in general doesn't seem to be very contagious.

Also, some experts question whether the infections are becoming more common.

Dr. William Schaffner, professor and chair at Vanderbilt's Department of Preventative Medicine, said that this bacteria were "not epidemic or communicable in the conventional sense" and that perhaps "we are just better at making the diagnosis."

Still, the random nature of flesh-eating bacteria and its ability to infect both the healthy and sick is frightening. Shanley said this is evident in the nature of the treatment.

"Antibiotics alone are never enough, and extensive surgery is the rule."

Today, out of the top ten countries with diabetes sufferers, seven are developing countries. The Caribbean and the Middle East have regions where the percentage of adults with diabetes has reached 20%. In certain parts of Africa developing diabetes can mean a short route to death. While patients in developed countries, with access to proper treatment, can expect to live for several decades, in countries such as Mali and Mozambique developing diabetes often means a life expectancy of one or two years.

The International Diabetes Federation released its data at the American Diabetes Association's 66th Scientific Sessions.

The spread of diabetes type 2 today is due to lifestyle, diet and genetics. Many more people today have better access to food, eat more of the wrong nutrients and do much less exercise. This combination of bad diet and inactivity leads to weight gain, which in turn raises the risk of developing diabetes type 2.

Here are some facts

-- The number of people with diabetes is expected to reach 350 million by 2025.

-- Top five countries with the most diabetes sufferers in 2003 were: India (35.5 million, China 23.8 million, USA 16 million, Russia 9.7 million and Japan 6.7 million.

-- Top five countries with the highest percentage of adults with diabetes in 2003 were: Nauru 30.2 %, United Arab Emirates 20.1 %, Qatar 16%, Bahrain14.9%, and Kuwait 12.8%.

-- The number of diabetes sufferers by 2025 is expected to: Double in Africa, the Eastern Mediterranean and Middle East, and South-East Asia, and rise by 20% in Europe, 50% in North America, 85% in South and Central America and 75% in the Western Pacific.

-- There are 6 million new diabetes sufferers in the world each year.

-- Every ten seconds someone in the world dies as a result of having diabetes - 3 million deaths a year.

-- Diabetes is now the fourth biggest cause of death worldwide.

-- Half of all diabetes sufferers around the globe do not know they have it. In some parts of the world 80% of sufferers don't know.

-- Diabetes causes more cases of blindness and visual impairments in adults than any other illness in the developed world.

-- One million amputations each year are caused by diabetes. A diabetes sufferer is up to 40 times more likely to need a lower-limb amputation when compared to a person who does not have diabetes.

-- Diabetes raises the sufferer's risk of developing a cardiovascular disease by two to four times. Cardiovascular disease, the number one cause of death in the industrial world, will soon be the number one cause of death globally.

-- It is estimated that diabetes accounts for 5% to 10% of most nations' health budgets.

-- If more money were spent on early detection of diabetes and diabetes prevention the economic savings would be massive.

-- Good control of blood glucose levels significantly reduces the diabetes patients' risk of developing complications. Managing hypertension and raised blood lipids is also crucial.

-- One quarter of all the countries in the world have not made any specific provision for diabetes care in their health plans.

Scientists believe that 80 per cent of the bugs are immune to over-the-counter lotions. They found lice were untroubled by the chemicals permathrin and phenothrin, found in popular bug-busting brands such as Lyclear and Full Marks.

The experts say the process of natural selection means the insects have developed a resistance to the lotions. The findings will not just leave children, parents and teachers scratching their heads. It will almost certainly start a scramble to discover a lotion to do the job better.

Lucrative

Eliminating head lice is a lucrative business, with Britons spending £30million a year on treatments.

Scientists at the Communicable Disease Surveillance Centre in Cardiff discovered four out of five lice were resistant to the chemicals.

A team led by Dr Daniel Thomas armed themselves with nit combs to visit 31 schools in Wales. Eight per cent of children tested had head lice and researchers managed to remove 4,000 nits - head lice eggs - from itchy heads. Each nit collected was tested for resistance to pyrethroids, which are used in the most popular treatments for lice.

They require a shorter application time and do not smell as strongly as other chemicals. More than 80 per cent of the lice were resistant to the insecticides which are designed to attack the insect's nervous system, the scientists discovered.

This was because of the process of natural selection, said Dr Thomas. Most lice have developed a gene which makes them more resistant to poisons following years of exposure to the chemicals.

Insects either develop ways of counteracting the chemicals before they affect their bodies or they become less sensitive to them, said Dr Thomas, whose findings are published in the journal Archives of Disease In Childhood.

He said there was no reason to suppose the findings would not be replicated across the rest of Britain.

Head lice live close to the scalp, where there is guaranteed warmth, food and shelter. They cannot fly, jump or hop and are spread when people's heads touch each other.

Last year a study found those who fine-combed their wet hair were four times more likely to remove head lice than those relying on products bought at the chemist.

A report by German researchers Thomas and Martina Grüter is expected to be published in a prominent American genetics journal within weeks. Harvard researchers announced May 31 that, by using different methods, they had come up with a similar number, though the data has not yet been published.

"It's a possible stealth condition," said Ken Nakayama, a Harvard psychology professor who led the research. "There is no test for this when you're going to school."

Born prosopagnosics, whose brains are usually normal in other respects, often suspect that something is wrong, but cannot put a finger on it. The condition also goes undetected because born prosopagnosics have never seen faces any other way, so to them, it seems normal, Nakayama said.

But sometimes, the problem "slaps prosopagnosics in the face, and they realize something's really wrong here," said Bradley Duchaine, a former Harvard researcher now at University College London. "I hear parents who go to the day-care center, and for some reason their kid has changed clothes while there, and the parents have no clue who their child is, while the people working there think, 'What is wrong with this parent?' "

Face-blind people can see faces perfectly well -- the eyes, nose, and mouth -- but seem to have trouble processing what they see and placing it into memory to be recalled again. In its rare, extreme form, prosopagnosics describe looking into the mirror and being unable to recognize themselves.

More often, they have trouble recognizing acquaintances and coworkers, social handicaps that can hurt their careers and their private lives. They tend to cope using a variety of ways to tell people apart, based on the sound of a voice, the style of clothing, or their walk. Or they "adapt by being smiling and friendly to everybody," said Richard Russell, another Harvard researcher.

Researchers say public attention to prosopagnosia (pronounced proso-pahgNOsia, and often shortened to "proso") may help people who have it, simply by making their lack of recognition more understandable to others.

Prosopagnosics are already debating whether schoolchildren should someday be tested for face-recognition problems.

"This is about as many children as have dyslexia," Thomas Grüter said, "and these children are not really handicapped in any extensive way, but still they might become outsiders, and this is something that could be avoided easily, just by telling kindergarten or primary school teachers what to do and how to help them. "

There is no known cure for the condition, but researchers are experimenting with training that could, at the least, help those with face-blindness better recognize relatives, friends, bosses, and other key people in their lives.

One Cambridge prosopagnosic, who asked not to be identified because she works in public relations and fears that her career could be damaged if her problem were known, said she has learned never to say, "Nice to meet you," but rather, "Nice to see you." Still, it can be embarrassing and comical to her friends when, for example, she fails to recognize a man she has dated.

In the Harvard research, the 2-percent figure is just a "best guess" at this point, Nakayama said, but it emerged when Harvard colleagues gave some 1,600 volunteers a variety of psychological tests, among them the "Cambridge Face Memory Test," which Nakayama had been working on for years and published last fall.

(It is not publicly available because researchers do not want potential subjects to become familiar with it. Duchaine offered a link for readers who want to quiz themselves: www.icn.ucl.ac.uk/facetests/.)

Thomas and Martina Grüter, the German researchers, became interested in prosopagnosia when, after watching a television documentary on the subject, Martina realized that Thomas's quirks -- needing her to identify people for him at parties, for example -- amounted to face-blindness. His father had it, too.

They hunted down more families and Martina wrote her thesis on the genetics of face-blindness, which seems simple: it appears to involve a single, dominant gene, so a child can inherit prosopagnosia even if only one parent has it.

The Grüters tried to figure out how common the condition really was. They handed out questionnaires to some 800 Münster high school and medical students, asking about experiences that might suggest prosopagnosia, and interviewed students who seemed likely candidates.

From among 800, they confirmed that 17 had a significant level of face-blindness, to the point that it caused problems in their daily lives .

The Grüters' paper, written with Ingo Kennerknecht, was accepted last month by the American Journal of Medical Genetics and is scheduled to be published online in the next three weeks, Thomas Grüter said.

The Grüters are now interested in finding ways to screen children for prosopagnosia and then to help those who are identified without publicly identifying them.

What goes wrong in the brains of face-blind people is largely a mystery, said Dr. Marlene Behrmann, a brain scientist at Carnegie Mellon University.

The phenomenon plays into a major debate in neuroscience, she said, whether the brain is made up of a bunch of separate little modules that each perform a different function or whether all parts of the brain are potentially capable of performing any function. "The truth will be somewhere in the middle, which is why it's a vigorous debate," she said.

If face-blind people have problems only with faces, that would tend to support the view of the brain as made up of task-specific modules, she said. But if, as some research suggests, the problem turns out to involve not only faces but also any objects that look alike, then it supports the idea that the brain uses more general visual processes.

Meanwhile, prosopagnosics such as Glenn, a Brookline cashier, say their lives are complicated both by their face-blindness and by the fact that nobody has heard of their condition.

"It would be really swell for me to be able to walk on the street in Harvard Square and say to somebody, 'You know, I have prospagnosia,' and for them to say, 'Oh, yeah, I know exactly what that is,' but I can't do that right now," said Glenn, who asked that his last name not be used for fear that someone might victimize him, knowing he could never identify them.

Glenn said he recognizes people by their trappings and context. He explains his problem to some people, asking them to realize that he may not recognize them when he meets them again.

Carey Goldberg can be reached at at goldberg@globe.com.
© Copyright 2006 Globe Newspaper Company.

I loved Teflon.
I loved the no-carb ricotta pancake I invented last year, which can be cooked only on Teflon. I loved my Teflon-coated frying pan, which makes a beautiful steak. I loved Teflon as an adjective; it gave us a Teflon president (Ronald Reagan) and it even gave us a Teflon Don (John Gotti, whose Teflon-ness eventually wore out, making him an almost exact metaphorical duplicate of my Teflon pans). I loved the fact that Teflon was invented by someone named Roy J. Plunkett, whose name alone you might have thought would have insured Teflon against becoming a dangerous product.

But this year DuPont, which makes polytetrafluoroethylene (PTFE) resin, which is what Teflon was called when it first popped up as a laboratory accident back in 1938, reached a $16.5 million settlement with the Environmental Protection Agency; it seems the company knew all along that Teflon was bad for you. It's an American cliché by now: a publicly-traded company holds the patent on a scientific breakthrough, it turns out to cause medical problems, and the company knew all along. You can go to the bank on it.

But it's sad about Teflon. Teflon wasn't really good when it first came onto the market. The pans were light and skimpy and didn't compare to copper or cast iron. They were great for omelettes, and of course, nothing stuck to them, but they were nowhere near as good for cooking things that were meant to be browned, like steaks. But then manufacturers began to produce Teflon pans that were heavy-duty, and you could make a steak that was as dark and delicious as one made on the barbecue. Unfortunately, this involved heating your Teflon pan up to a very high temperature before adding the steak, which happens to be the very way perfluoroctanoic acid (PFOA) is released into the environment. PFOA is the bad guy here, and DuPont has promised to eliminate it from all Teflon products by 2015. I'm sure that will be a comfort to those of you under the age of forty, but to me it simply means that my last years on this planet will be spent, at least in part, scraping debris off my frying pans.

Rumors of Teflon have been circulating for a long time, but I couldn't help hoping they were going to turn out like the rumors of aluminum, which was suspected (back in the nineties) of causing Alzheimer's. That was a bad moment, since never mind giving up aluminum pots, it would also have meant giving up aluminum foil, disposable aluminum baking pans, and most crucial of all, anti-perspirants. I rode out that rumor, and I'm pleased to report that it went away. (So has my memory, but I think that's a coincidence.)

But this rumor is clearly for real:

A few days ago, Marian Burros, the incontrovertible food writer for the New York Times, announced that she had moved her Teflon pans to her basement. I notice that she did not throw them out (which I'm going to have to do, since I have no basement). She tested a zillion other pots and made a trillion omelettes, and she wrote that the black enamel frying pan made by Le Creuset was as good as Teflon and even managed to cook eggs that didn't stick. Today I am going to go out and attempt to buy one. My guess is that there are none left in the city of New York.

After I find one, and not a moment before, I will throw my Teflon pans away. Meanwhile, this morning, I am going to make one last ricotta pancake breakfast:

Beat one egg, add 1/3 cup fresh whole-milk ricotta and whisk together. Heat up a Teflon pan until carcinogenic gas is released into the air. Spoon pancakes onto the frying pan and cook about three minutes on one side, until brown. Carefully flip. Cook for another minute to brown the other side. Eat with jam, if you don't care about carbs, or just eat unadorned. Serves one.