|Search ON THIS DAY by date|
The fire broke out early this morning in a storage building used for pesticides, mercury and other highly poisonous agricultural chemicals.
Local residents were woken by sirens sounded by local authorities to alert them to the disaster.
People in the city of Basel and the surrounding region on the border between Germany and France were told to stay indoors.
Witnesses reported a foul smell of rotten eggs and burning rubber.
Fourteen people, including one of the firemen fighting the blaze, were treated in hospital after inhaling the fumes.
It is thought the chemicals were washed into the river in the water used by firefighters to tackle the fire. The West German Chemicals Industry Association is to carry out an internal report and says it could take weeks to determine the cause of the disaster.
The factory is owned by Sandoz, one of Switzerland's largest chemical firms.
About 30 tons of pesticides were discharged into the river, western Europe's most important waterway.
The river flows through four countries - Switzerland, Germany, France and Holland - before flowing into the North Sea.
Environmentalists are now struggling to prevent the pollution sweeping down the Rhine and into the rest of Europe.
The spillage has reversed 10 years of painstaking work to clean up the Rhine, so grossly polluted by industrial expansion in France, Germany and Switzerland that fish disappeared and it was too dangerous to swim in.
The Dutch are particularly concerned about the presence of mercury in the chemical cocktail now heading their way.
A similar pollution incident in Japan 25 years ago revealed the extremely poisonous nature of mercury after fish were contaminated and then caught and eaten by fishermen and their families in the area.
Hundreds of people suffered an agonising death as a result of that incident, which saw mercury deposits similar to those expected to accumulate along the North Sea coast near Holland.
The leak at the Sandoz factory was Europe's worst environmental disaster for a decade.
Within 10 days the pollution had travelled the length of the Rhine and into the North Sea.
An estimated half a million fish were killed, and some species were wiped out entirely.
There was a public outcry, resulting in the Rhine Action Programme of 1987, sometimes known as "Salmon 2000" because its stated target was to see the return of salmon to the Rhine by the year 2000.
The agreement achieved a 50% reduction in pollution by nitrates and phosphorus in the river, and some other types of pollution have been reduced by 80 to 100%.
Salmon - known for its sensitivity to water pollution - returned in 1997, three years ahead of schedule.
The Rhine 2020 Programme aims to make the Rhine clean enough to swim in.
The chemical companies around Basel have increased their safety precautions, including giant catch basins to trap water used in putting out fires.
The chemical firm Sandoz merged with fellow chemical company Ciba-Geigy in 1996 to form Novartis, a world-leading drugs and chemicals company.
|Search ON THIS DAY by date|