AN expert in public and environmental health has called on the Scottish Government to make its moratorium on fracking permanent, following a critical report on the practice in Texas which found that it pollutes the air, erodes soil and contaminates water.

Professor Andrew Watterson, chair in health effectiveness at the University of Stirling, was speaking after the study by a task force set up by the Academy of Medicine, Engineering and Science of Texas found that the shale oil boom had also degraded natural resources and overwhelmed small communities.

The report noted that the second-biggest state in the US had no single database tracking environmental impacts. It had no system for conducting regular research on the effects on plants and animals and had little detail on spills of waste water from shale drilling and fracking. There was also limited data on exposure to toxins in the air.

Kris Nygaard, a consultant for Exxon Mobil who took part in the study, said: “There’s significant debate in the public about shale development. And I think we can all agree the most healthy and informative debates surround real data, hard facts, hard information.”

However, Watterson said he found disturbing the lack of research about the potential effects of fracking.

He told The National: “There’s a classic statement that the absence of evidence isn’t evidence of absence – and what you’re expecting to see is evidence of things that have been assessed – the data are there and there isn’t a problem, whereas what they’re actually saying is, ‘oh we don’t know’.

“There are reasons sometimes why organisations and industries do that. It’s a vicious circle – if you don’t look you don’t find, if you don’t find, it’s not a problem – let’s carry on.”

Watterson said the report strengthened the case for Holyrood to make the moratorium on fracking permanent.

He said: “If you use the precaution- ary principle on the basis of the information in the Texas report, it does not give fracking the green light.

“So if we’re talking about countries and states that have used the technology for some time then it doesn’t give it a clean bill of health.

“I think on the basis of the precautionary policy that’s what New York State did.

“Not only do we know certain things are problematic, but there’s a lot that we don’t know, so we shouldn’t be doing it, particularly in the Scottish context where the benefits were relatively small economically, social disruption and social impacts were pretty large and certainly in the medium term we have alternative supplies of sustainable energy.”

The Texas study is likely to increase scrutiny of fracking, but nobody – including the scientists involved – expects companies to slow production. However, Watterson said he remained disturbed by the degree of ignorance about fracking’s possible impacts.

“There are lots of issues, partic- ularly as Texas and so on in the past have been a bad example, but the industry over here now says all the problems are sorted,” he said.

“So when you read that and see for instance they don’t have any idea about what the health effects might be, then I think that is worrying, as are the specific things they have about impacts on the environment; seismic issues which may or may not appear in the same way in Scotland.

“It’s a fairly long list of what I would say are either problems or significant gaps that don’t allow you to make a statement that fracking is fine in the US.”

Watterson added it was ironic reports had suggested the UK could be self-sufficient in energy, just as we are looking at use of a short-term source such as shale. He said: “Shale gas will run out, probably won’t be economic and doesn’t bring many benefits. If you add it all together it doesn’t provide a very positive picture.”

A Scottish Government spokesperson said: “No fracking or drilling for coal bed methane can take place in Scotland as a result of the moratorium already put in place by the Scottish Government. Our public consultation on unconventional oil and gas, Talking Fracking closed on 31 May and the responses are being independently analysed.

“No decision on the future of unconventional oil and gas will be made before the Scottish Parliament has had the opportunity to vote on the matter‎.”