Chemicals found in cigarette smoke have been shown to damage foetal liver cells, but they affect boys and girls differently.
Mundell: No Plans For Second Indy Vote
The Scottish Secretary has said there are no contingency plans for the possibility of a further referendum on independence after next year's Holyrood elections.
David Mundell called on the Scottish Government to clarify its position on another vote in his response to parliamentary questions lodged by SNP MP Margaret Ferrier.
With opinion polls pointing to the possibility of a SNP landslide in the Scottish Parliament elections, the move sparked speculation a second vote could be on the cards, despite Scots rejecting independence by a majority of 55% to 45% in last September's referendum.
Mr Mundell said he was "disappointed'' by the questions in light of statements made by Scottish First Minister and SNP leader Nicola Sturgeon and her predecessor Alex Salmond that the referendum was a ``once-in-a-generation'' opportunity.
Ms Ferrier had asked the UK Government minister to set out ''what contingency plans his department has prepared for the possibility of a further referendum on Scottish independence being the policy of the Scottish Government after the Scottish Parliament election in 2016''.
The Rutherglen and Hamilton West MP also put forward a second question asking what assessment had been made ''of the implications for his policy on a further referendum on Scottish independence of the Scottish Parliament election in 2016 delivering a majority for political parties committed to the holding of such a referendum''.
In response, Mr Mundell said: "Given the clear and repeated commitments of leading Yes campaigners, not least the First Minister herself, during the independence referendum campaign that the vote was a 'once in a generation' or 'once in a lifetime' event, and given that a clear majority of Scots voted No in that referendum, my Department has not prepared contingency plans for the possibility of a further referendum being the policy of the Scottish Government after the Scottish Parliament election in 2016.''
He added: "The Scottish Government's White Paper on independence said a referendum was a ''once in a generation opportunity" - this makes answering questions on preparations for a second referendum all the more disappointing.
"We're approaching one year on from the referendum where the people of Scotland voted decisively to remain part of the United Kingdom. Yet the noises are growing from those who want to begin a countdown towards a second referendum.
"It does no favours to use talk of a second referendum as a cloak to avoid talking about what the Scottish Government can do with the powers they've got and what they can do with the substantial powers which are on the way through the Scotland Bill.''
An SNP spokesman said: "The timing of any future referendum is entirely a matter for the people of Scotland to decide - the people, not politicians, are in charge at every stage of the process.
"The First Minister has made clear we are not planning another referendum, but equally has made it clear that it is not in the gift of any politician and party to rule it out indefinitely.''
The SNP leader is hoping to build on her party's 2015 success of winning a record 56 out of 59 Scottish Westminster seats.
The powers include responsibility for Ill Health and Disability Benefits, Carers Allowance, Cold Weather Payments and Winter Fuel Payments.
The update in the high-profile litigation comes after a judge overseeing the action granted a series of adjournments to allow settlement discussions between investors and the bank.
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