MAD COW DISEASE

First surfaced in Britain in 1985 when a black-and-white dairy cow was seen staggering and head-butting other cattle. It was diagnosed as BSE in 1986.

Known formally as bovine spongiform encephalopathy (BSE), the disease swept through Britain in the 1980s and early 1990s, causing millions of animals to be slaughtered and burned. During this time, Britain culled 3.7 million cattle and spent more than $6 billion, excluding job losses, in sorting out the crisis.

Scientists blamed waste produced in slaughterhouses used to make animal feed for its spread. Cattle feed usually contained wastes obtained from the slaughter of other cows.

By 1988 Britain realised that BSE was a serious problem. EU authorities banned high-risk materials such as spinal cord from use feed and tighter labelling was also introduced.

In early 1997, the European Commission - rocked by accusations of incompetence over its handling of the BSE crisis - agreed an internal shake-up. Hiving off its veterinary services from the powerful agriculture department, seen by some as defending farmers' interests, it created a food safety unit.

British beef exports were banned worldwide.

The rest of the EU was not immune to BSE either and cases were seen in many other countries. Nearly all EU states have now reported BSE cases - Sweden saw its first case this month.

But the overall incidence of BSE in the EU is falling.

The ban on British beef exports was partially lifted in 1999. In March 2006, EU experts agreed to a complete lifting of the embargo - nearly 10 years to the day after it was imposed.

FOOT-AND-MOUTH

As Britain began to emerge from its BSE crisis, the country became the focus of a major scare over foot-and-mouth disease (FMD). It began in 2001 in an abattoir in southern England and spread to several other EU countries before it was eradicated.

It turned into one of the world's largest and most expensive animal disease outbreaks, with overall costs estimated at up to 12 billion euros. France, Ireland and the Netherlands were also hit and all four countries managed to win some EU compensation.

The outbreak ravaged Britain, where authorities slaughtered 6.5 million animals and burned them on giant funeral pyres to stem the spread of the highly infectious disease - turning much of the countryside into a no-go zone, rather than use vaccines.

Britain's government came in for heavy criticism for its handling of the outbreak as it failed to stop the movement of animals as soon as FMD was discovered.

Foot-and-mouth causes high fevers and blisters in cloven-hoofed animals and can often lead to death. The highly contagious disease can be contracted by cattle, pigs, sheep and goats, but very rarely by people.

DIOXINS

Next came cancer-causing dioxins, a broad family of chemicals formed by both man-made and natural events, which have featured regularly in EU health scares.

Dioxins are accidental by-products generated mainly through incineration by the chemical and pharmaceutical industries and can be absorbed through the skin or eaten in food.

They remain in the atmosphere for a long time and can become trapped in fatty tissues once absorbed by animals. Scientists have linked dioxins to birth defects and brain damage.

In 1999, dioxins were found to have entered the food chain in Belgium via animal feed made with contaminated fats.

Shop shelves across the country were stripped of products and countries around the world banned imports of Belgian meat and dairy products as a result.

Earlier this year, they re-emerged when more than 650 farms were quarantined in Belgium, Germany and the Netherlands after the chemical was found in ingredients that were used in feed.

ILLEGAL DYES