Five leading chemical groups have been hit with fines totalling EUR243.21m (US$353.9m) by the European Commission for taking part in a cartel for chloroprene rubber.

Bayer from Germany, DuPont/Dow from the US, ENI from Italy and Tosoh and Denka from Japan participated in the illegal cartel from 1993 to 2002, the Commission said.

The companies "shared the market and fixed prices" for the rubber, which is used in the inner soles of shoes, among other industrial uses.

ENI was particularly hard-hit, seeing its fine increased 60% to EUR132.16m because of previous fines for similar offences.

Bayer would have seen its fine increased 50% to EUR201m for the same reason, but was exempted from all fines as it had been the first company to come forward and tell the Commission about the cartel.

Tosoh saw its fine halved to EUR4.8m because of its co-operation in the investigation, while DuPont/Dow had a 25% reduction to EUR59.25m for the same reason.

Denka was fined EUR47m with no reduction.

The Commission said the companies had held regular meetings from 1993 to 2002, discussing prices, exchanging sensitive information, discussing clients and following up the implementation of previous illegal agreements.

"It is particularly disappointing that the rubber industry has still not learned its lessons about avoiding cartels," said Competition Commissioner Neelie Kroes. "I find it very difficult to understand how shareholders and board members can tolerate such illegal behaviour."