An unusual problem has disrupted rail services in south-east Sweden - a high pollen count.

The trains are not suffering from hay fever, says Jenny Arklund of the train company Oestgoeta Trafiken - the sticky yellow particles clog up air filters and cause engines to overheat.

From mid-May to mid-June a total of seven services between Linkoeping and Kalmar had to be cancelled.

"The weather this year has been very hot and dry, and there was lots of pollen - an unusual amount," Ms Arklund told BBC News Online.

Lifeline

Given that there are up to 15 train services per day, in both directions, a total of seven cancellations in a month might not, in some countries, be regarded as serious.

The Kustpilen train has problems in winter, spring, autumn, and now summer

Buses were laid on to replace the train service.

Ms Arklund, however, is not happy.

"I hope this is unique - and that it won't happen again," she said.

"We think it's a large number [of cancellations] because we want our passengers to be content."

The train makes 10 stops at small villages between Linkoeping and Kalmar, and for people who live in them the train is a lifeline.

Wet leaves

"Trains have a symbolic value in Sweden," she said.

The train is very nice in some ways, but we have had some bad luck

Jenny Arklund, Oestgoeta Trafiken

"You feel you are connected to the outside world, and have the possibility to move around and receive goods and people."

The service was stopped 30 years ago, but began again in 1996.

The Kustpilen trains, built by the Danish firm Adtranz, are very comfortable, Ms Arklund says.

However pollen is not the only thing that stops them.

Wet leaves on the line, in spring and autumn, and cold winter weather have also led to cancellations.

"The train is very nice in some ways," says Ms Arklund, "but we have had some bad luck."