In Paris, 19-year-old Arnaud Eboli lies dying from the human version of mad cow disease, Variant Creutzfeldt-Jakob disease. His parents told a BBC reporter Britain was to blame.

M. EBOLI: We think it`s the British because the disease... From what we`ve heard and seen in previous years, the disease comes from Great Britain.

MME EBOLI: I think it`s the British, because when it became known that the offal and animal meal were contaminated, you got rid of them by selling them to us at low prices.

Mr And Mrs Eboli have filed a lawsuit which accuses persons unknown of manslaughter and poisoning - a case which could embroil the British and French governments.

Across the Channel in Britain, 83 people, many of them teenagers like Zoe Jeffries, have already died from CJD. The government now states that up to a quarter of a million citizens could be infected. Many health professionals in France fear they may be in for a similar epidemic.

FRENCH DOCTOR: Sometimes we worry because we`re facing an unknown. We don`t know the exact number of cases. We only know it won`t go away soon. But we can`t give an exact figure. Estimates vary from two to six figures.

This is where it started, on a Wiltshire farm in England, where 18 years ago the first of 180,000 British cows displayed the end-stage symptoms of bovine spongiform encephalopathy, or BSE. Scientists became convinced BSE was being spread by cannibalism, feeding ground-up cows and sheep back to cows - a common practice of modern industrial farming.

Though Britain banned the feeding of meat and bone meal to its own cattle in the late `80s, it continued to export it. France and Germany imported thousands of tonnes of feed for its cows for at least another two years, and continued to import the feed for its other animals until 1996.

One of the scientists who publicly opposed those exports was Dr Stephen Dealler, who remains at the forefront of the mad cow debate in Britain.

DR STEPHEN DEALLER, MICROBIOLOGIST: All you`ve got to do is to realise just how much was exported in such large amounts, and then realise that really, the genie is out of the bottle and the disease has got out from Britain. It`s going to be very, very difficult to stop now.

The World Health Organisation says there`s no doubt infected meat and bone meal from Britain spread mad cow disease to the rest of Europe.

DR MAURA RICKETTS, WORLD HEALTH ORGANISATION: It`s very clear that the exportation of this contaminated animal feed into the European Community is how the European Community became seeded with BSE. In some of the European Community countries, the fact that they recycled rendered material into animal feed is how they`ve continued their epidemic.

France was one of those countries. For years, it ignored the growing evidence in Britain, and while a ban on British beef was maintained, the government may have allowed dangerous practices to continue. Through its advertisements, the industry claimed that because it was French, it was safe.

FRENCH BEEF INDUSTRY TV COMMERCIAL: We can guarantee the region of origin of French beef by the identity card every animal carries. You can rest assured that the meat on your plate has the authentic character of the meats of our regions.

But the French public recently learned their meat was not safe. More than 260 BSE-infected cattle have been discovered, most picked up by testing over the past year. It`s believed many more remain undetected.

Farmers like Marjolaine Maurette say the public has been deceived.

MARJOLAINE MAURETTE, FARMER: They`ve led consumers to believe that a guarantee of the beef coming from France also guarantees that it`s good meat - good in terms of taste and good in terms of hygiene. But in fact, except for the guarantee that it`s French, there`s no guarantee about how the animal was fed and there`s no guarantee that it will even taste good. There`s just this advertising campaign about tracing the cows` origins which, in fact, misleads consumers.

DR STEPEHEN DEALLER: I have to admit, the gravest fears are being seen in France and Germany at the moment, where the cows they`re seeing going down with BSE are actually quite young - they`re aged four, five, six years. In other words, they became infected in the middle of the 1990s, and that`s not the time that we exported the BSE-containing meal to them. In other words, we exported material to them, they fed it to some cows, the material then from those cows was fed to further cows. And if you try and do a little bit of maths, you can suggest that all you`ve got to do... that process multiplies the numbers dramatically.

Maurette fattens her cattle with commercially-produced protein-rich granules. This feed is no longer supposed to include the remains of cows or other animals, which was officially banned in 1990. Yet despite the ban, French cattle may have been fed meat and bone meal, or MBM, for years - if not deliberately, then by accident.

MARJOLAINE MAURETTE: The trucks that transport animal feed aren`t cleaned after every trip, because I find some of these granules in my deliveries. Who knows what they are? They could be for ducks or pigs. But one thing is for sure - they`re not for ruminants. Which demonstrates that we cattle breeders don`t have full control over what we feed our animals. Every time we buy a commercial product, we lose that control.

DR STEPHEN DEALLER: My fear for France is in fact that infected cattle were still being fed to further cows by using meat and bone meal as late as 1999 - that even in France, the directives to stop the use of meat and bone meal did not work. That is the greatest worry. Germany didn`t take major action until last year, until October of last year. I mean, I think if I was going to have any worries for particular countries, I`d worry for Germany the most, because by the time you see an epidemic starting - which is what they`re seeing at the moment - the signs of the epidemic you`re going to see is so large, you could hardly imagine it.

Germany has followed France by banning the feeding of meat and bone meal to all animals. Both countries have learned some of the lessons from the British epidemic, but not all.

After years of producing milk, worn-out cows come here to die. These animals have been ingesting feed supplements for years and are therefore more likely to be carrying disease. But unlike Britain, where animals of this age were removed from the food chain, until last month, these cows were destined for French dinner plates after only cursory inspections.

VETERINARIAN: It`s a visual inspection of the offal and carcass to see if there are any abnormal colours or deformations. We also hand-examine the offal, looking for any unusual hardness or an overly crumbly liver. We also make a certain number of mandatory incisions in the lungs and liver, for instance, to see if there are any internal lesions.

The gut of a cow slips past without even a basic check.

VETERINARIAN: It went by too fast. He couldn`t hold on. He didn`t have time to make the incisions.

Yet visual inspections mean nothing when it comes to BSE, which is invisible to the eye. The safety of eating French beef has depended on the removal of all high-risk matter, particularly the brain and spinal cord. Yet here, the removal of the spinal cord is a sloppy procedure, and the vet admits parts can be left behind.

VETERINARIAN: It can happen, of course.

BSE is highly infectious. An amount the size of a peppercorn is thought to be enough to infect a whole cow. The European Union`s Scientific Steering Committee believes one infected animal in the food chain could put at risk a staggeringly high number of humans.

GERARD PASCAL, EU SCIENTIFIC STEERING COMMITTEE: We found that if the specified risk material is not removed, just one infected animal that enters the food production chain can expose - in very low doses, of course - but it can expose hundreds of thousands of consumers to BSE.

Independent epidemiologists have estimated that at the minimum, 100 infected cows were eaten in France last year alone and that 1,000 French people may already be infected.

To eradicate mad cow disease once and for all, the European Union has banned all cattle over two and a half from entering the food chain unless tested for BSE. But the Swiss scientist who invented one of two BSE tests says that will not prevent people from eating infected cattle.

Every morning at this rendering factory in Switzerland, Dr Ruedi Muller extracts brain matter from dead cows. The brain samples are analysed in a Zurich laboratory. Last year, more than 20 cases of BSE were discovered using this procedure. But the co-inventor of the test, Dr Markus Moser, says the results are limited, that the test can only detect BSE in the few months before the appearance of symptoms.

DR MARKUS MOSER, PRIONICS PTY LTD: For years sometimes the cow can be infected but there are no symptoms, and also in the last phase of the disease, where the cow really gets dangerous because there are high amounts of infectious material in the brain and in other organs, even then the cow does not show symptoms yet. It`s only in the very, very last phase of the disease where the symptoms are easily recognised.

Dr Moser acknowledges that his test cannot guarantee a cow is free of BSE.

DR MARCUS MOSER: With our test, we detect animals which have 100-fold less infectivity than animals with full-blown BSE. But if you have an animal that has 10,000- or 1 million-fold less infectivity, you could argue, of course, then it might not be dangerous, because it`s only a little bit. But we don`t know exactly. We don`t know how much it takes for a human being to be infected. So we cannot guarantee any safety with any measure.

A number of scientists and the World Health Organisation have questioned the European Union`s use of a limited test as a guarantee of food safety.

DR MAURA RICKETTS: What we`ve seen from this diagnostic test so far is that it has a really top-notch value in supporting surveillance systems. In terms of whether or not it can be used to guarantee food safety, I think that`s another matter entirely.

DR STEPHEN DEALLER: I think it`s to do with money. I think that they`re looking at Europe at the moment and saying there`s not really very many cattle over 30 months that are infected. If we just stop eating all of those, it will cost us so many million Euros, and it`s not worth the money. I`d guess it`s something to do with cash.

For five years, Britain has killed every cow over 30 months. Here, the meat is spray-painted to prevent it being sold on the black market. Millions of carcasses have been ground into beef powder, and there the process comes to a halt. Britain doesn`t have the means to incinerate all of it, so more than half a million tonnes are rotting in storage.

Other European countries have begun slaughtering cattle. Germany is to destroy up to 500,000. But will the mountains of waste create another potentially deadly problem, and how will individual countries handle the storage of thousands of tonnes of banned meat and bone meal?

DR MAURA RICKETT: What`s happening with all of this stored material? If bovine animals and sheep aren`t allowed to eat this meat and bone meal anymore, it`s been stored all over the European community in the UK inside storage houses, and a lot of work is being done to protect it. But one can always imagine it`s possible for small rodents or birds to enter into these storage facilities, or even that there could be damage to the buildings and that the materials could leak into the environment or contaminate the waterways. So in fact, scientists have tried to do risk assessments on whether or not there could be environmental contamination from these materials.

It was Dr Ricketts`s team at the World Health Organisation which, by examining export and Customs records, discovered the extent of Britain`s culpability in the spread of BSE. Not only did Britain export to Europe - meat and bone meal, brain tissue, live cattle and human food was sold to Africa, North America, the Middle East and Asia. Large amounts went to Israel, South Africa and Thailand.

DR MAURA RICKETTS: It`s very important for nations themselves to review their own risks, to consider whether or not they imported these kinds of potentially contaminated materials, like the meat and bone meal or animal feeds, from the UK, or from the European Community for that matter, and then determine how did they use it. Did they use it in bovine populations? And if they did, they may have accidentally introduced BSE.

DR STEPHEN DEALLER: I knew it was going on, and myself and a number of MPs at the time tried to prevent it. But people inside the Ministry of Agriculture also knew it was going wrong and did not try and stop it. The Ministry of Agriculture itself in the UK was quite aware it was happening. They`d actually checked with the government at the time that that was acceptable, and they decided to send letters to each individual government that was receiving the material and just to tell them, "Don`t feed it to your cows." I don`t know what happens to your government, but if I send a letter to my government saying something like that, it would just end up in a pile of paper and nothing would ever happen.

To make matters worse, European countries routinely onsold meat and bone meal imported from Britain.

DR STEPHEN DEALLER: It went to European initially and was re-exported from warehouses in Rotterdam, for instance, in bags to somewhere else. I wish we knew, but these things were never written down, they were never kept, and they`re probably not even marked on the outside of the bag. It probably didn`t even say "meat and bone meal." It probably just said "food for chickens" or something like this.

DR MAURA RICKETTS: My greatest fear is that BSE has been seeded into a country where they have a fairly substantial population of cattle and where they might also have a rendering industry, and the rendering industry component is very important. One of the things that can be done with this rendered material is making more feed for cattle. And it`s a very efficient source of protein for cattle, of course, but it can recycle this agent. That would be my single greatest fear.

The revelations raise the spectre of future BSE and Variant CJD epidemics in some of the poorest African and Asian countries.

REPORTER: Is there a sense in Britain today that it was wrong to continue to export the feed?

DR STEPHEN DEALLER: Oh yes, yes. The Phillips inquiry which came out in October of last year made it absolutely clear that that was a grave error. Well, if the Phillips inquiry says it`s a grave error, legally that is going to be very difficult to deny, and when I look at this, I realise that it puts the British government in a very bad position if people in Europe want to take them to court, for instance.

In Paris, lawyers representing Mr and Mrs Eboli have signalled they intend to make Britain pay for its grave error.

EBOLI FAMILY LAWYER: We approached the British government who have decided to export so much into the EC, using the facilities of the common market. As you know, the British government got problems to export worldwide, especially and even in Commonwealth countries. So it`s amazing that the common market should be used as a cattle basket, a sort of rubbish place.

If all that wasn`t bad enough, there are now concerns over other ways in which mad cow disease may be transmitted. Blood transfusions and organ transplants have come under suspicion. But the World Health Organisation is now raising with governments another fearsome possibility - that sheep, already carriers of a similar disease called scrapie, may have contracted BSE through contaminated feed.

DR MAURA RICKETTS: There have been experiments that have shown that sheep are susceptible to BSE - not scrapie, BSE; two different kinds of agents inside the same family. We`d be very worried about this, because those experiments, although there are a very small number of them, found that the disease of BSE in sheep is not so easy to distinguish from the disease of scrapie in sheep, which is a fairly common disease of sheep. So we`re very concerned, because obviously sheep were exposed to this potentially contaminated meat and bone meal in feed. I don`t think there could be any doubt about that. We know that BSE and Variant CJD are caused by the same agent. So clearly, if you just connect the dots, you`ll see you have to be concerned about whether or not human beings can acquire Variant CJD from sheep who have BSE.

Last week, food safety experts in France called for the brains, spines and intestines of sheep to be banned. After ignoring the crisis for much of a decade, Europe is in the grip of a panic. The mad cow genie is out of the bottle.