THE economic benefits of plummeting oil costs to businesses and consumers in Scotland are not offset by the impact of a growing industry and jobs crisis caused by the price crash, unions have warned.

The Scottish Trades Union Congress (STUC), in a submission to Holyrood's economy committee, said the net impact on the UK economy of the falling price - from around $115 a barrel last summer to well under $50 - had been positive as falling tax revenues were more than compensated for by a boost to household spending and businesses reliant on oil.

In March, a Fraser of Allander Institute regular forecast showed the boost to oil users in Scotland was outweighing the harm to North Sea producers.

However, The STUC said that for the Scottish economy, recent data indicated that the economic recovery had slowed significantly during the middle of this year and that the impact of a falling oil costs on the economy in the north east helped explain why.

It said that the situation had deteriorated since September, when it was estimated that 65,000 jobs had been lost as a result of the crisis facing the North Sea, and that significant future job losses can be anticipated. It added: "The STUC and the oil and gas trade unions are intensely concerned over the current state and future prospects of the oil and gas sector."

It warned that changes to terms and conditions are leaving staff in the sector working 12 hour shifts 21 days in a row, with health and safety being undermined and vital skills at risk of being lost with the price not forecast to rebound meaningfully until the end of the decade.

The submission added: "It must be stressed that the oil and gas industry is a very significant component of the Scottish economy. It is true that revenues which help support public spending have fallen precipitously and that, due to declining production and profitability, revenues were probably in secular decline prior to the current price collapse.

"Yet the industry continues to support many high skilled, relatively well paid jobs. The priority must now be to maintain employment and the fragile skills base within the context of excellent safety standards."

The STUC, despite acknowledging that it tends to be highly sceptical about claims of the "magical incentive" of tax cuts and believing the public should benefit from oil, is calling for George Osborne outline further measures in his Autumn Statement to assist firms.

However, it acknowledges even this would have "very limited short-term impact given that so few operators are currently paying tax due to low profitability."

Scottish Conservative energy spokesman Murdo Fraser said: "These bleak warnings indicate the depth of the recession in the oil & gas sector. The UK government has already delivered substantial tax changes to assist the industry, which were widely welcomed.

"There is always scope to look at what more might be done, particularly in deploying transferable skills, for example in engineering, elsewhere. Scotland has the potential to develop an onshore unconventional oil and gas industry which could support many thousands of jobs. It is a pity that the SNP's moratorium on fracking is denying Scottish workers these opportunities."

Scottish Labour Public Services spokesperson Lewis Macdonald said: "The oil jobs crisis has affected families across Scotland, not only workers in the oil industry and in the North East but households who rely on jobs in the supply chain across the country.

"It is an industrial crisis on a huge scale but the response from the SNP Government in Edinburgh has been to sit on their hands because the issue is politically embarrassing for them. After eight years in government and with a majority in the Parliament the SNP shouldn't have to be dragged to dealing with this."