Driving into the Maples estate on the outskirts of Frankfort in Kentucky, it is hard to ignore the ominous black stains hanging on to the sides of the houses. Built around 16 years ago, the area was to be a model community, with around 200 homes. Yet now, it is hard to sell here. The spreading black fungus sees to that.

When it first appeared, people did what they could to clear it. They scrubbed, and they power washed. They found that the strongest chemicals they could, and they seemed to work for a while. But the blackfungus appeared again, often darker and nastier than before.

Then in 2007 Canadian researchers published a study about a newly identified type of fungus called Baudoinia. Naturally occurring, it flourishes when it absorbs ethanol. 

Now, no more than 2km from the Maples estate is a distillery which produces Kentucky's famous bourbon whisky. There, they age the alcohol by storing it in barrels for a number of years. During the process some of the whisky evaporates into the wind poetically they call it 'The Angel's share' - that is ethanol.

Bill McMurry, an attorney, is heading a class action lawsuit against five distilleries claiming property damage and negligence. He wants the distilleries to stop the ethanol escaping and to pay for the clean up.

Mike Mills, an environmental engineer, and his wife first noticed the black stuff not long after they moved into the home they had bought to enjoy retirement.

"We didn't even know what it was to complain about it." After several years, he decided to sell his house, so he scrubbed it clean inside and out. A number of people came to see it.

"They told us they loved the house, but they weren't sure about the black stuff they saw on all the other houses," he said. He now wonders if he will ever be able to move.

Further down the street, a woman tells us to walk around to the back of her neat two storey home. The 'whisky fungus' is thick here, and it grows on everything, including garden furniture and even a child's plastic playhouse. There are two cars in the drive. The paint looks as if it is being swallowed up.

The distillers – including some household names like Jim Beam – say that the fungus has nothing to do with them, that it is naturally occurring and that if the case goes to court, then they will fight any action vigorously. A drive past some of their plants reveals the black fungus is also widespread there.

Looking for compensation

Some locals are worried about challenging the whisky firms. Kentucky's links with the drink are world famous, it draws tourists and provides thousands of jobs either directly or indirectly.   

"Some people say, 'Well, the distilleries were there before you were, so what's the big deal?' But it is a big deal," says Mike Mills.

"It's depressing to live with this, to see it every day and know it's hurting property values."

Bill McMurry – who sued the Vatican for its role in the child sex abuse scandal – believes the courts will order the distillers to stop gassing off the ethanol. He says some drinks manufacturers in California already do it. 

"That's not going to affect their bottom line or even the flavour of their whisky. And the cost over say ten years is so small," said McMurry.

He's now travelling to Scotland to sign up people who live near distilleries there for similar legal action.

"From the pictures, it looks much worse in Scotland, it looks like part of the architecture," said McMurry.  And he's considering taking his case to several more countries.

"This could go international" he said. Anywhere they have been producing spirits, Eastern Europe, South America, Canada, Cognac in France, well there could be people who are suffering with this problem.

There have been no long term studies to see if there are any health issues connected to the black whisky fungus. 

And if the courts back McMurry, it could cost the drinks makers tens of millions of dollars in damages a huge bill for an angel's share.