25/09/2013 07:48 BST | Updated 02/09/2015 07:59 BST

Mark Carney's Polymer Banknotes Could Be 'Cocaine-Free' - Experts

Polymer banknotes, the new note form which Mark Carney has suggested could replace the current cotton paper banknotes, could have an advantage of being cocaine-free as they would be harder to hold and less likely to retain the Class-A drug.

This comes after every British banknote was found to be contaminated with cocaine within weeks of entering circulation, with the contamination so widespread that police no longer bother to test for traces of the drug.

UCL chemistry professor Andrea Sella told the Huffington Post UK that polymer banknotes would "almost certainly" be "much less sticky for substances like cocaine".

Plastic banknotes are also harder to fold than paper banknotes and are specifically designed to resist such attempts as folding polymer banknotes would leave a permanent crease in the bill.

Polymer banknotes are already being used in countries like Australia, Zambia and Canada. The Bank of Zambia says the banknotes "tend to be harder to fold, and once folded they tend to be harder to flatten out again".

The Bank of Canada, which Mark Carney headed before taking over as Bank of England governor, advises keeping the banknotes flat and "not folded" in order to keep them in better condition.

Speaking to the Huffington Post UK, chemical experts have suggested that the new plastic banknotes be coated in a polymer fabric that would make them less likely to retain substances like cocaine.

Dr Paul Scott, of the Cambridge Design Partnership, told the HuffPostUK: "Polymer banknotes are likely to retain substantially smaller amounts of small solid particles, such as powdered cocaine, compared to the current material from which the Bank of England banknotes are made. It’s all due to scale and surface roughness.

Dr Scott said the Bank's intended material for banknote production, a polymer called polypropylene, would be more "impermeable" than paper. "It would be much harder for solid particles to become lodged in its super-smooth surface," he added.

The Bank of England launched its consultation on replacing cotton paper banknotes with polymer editions earlier in September, arguing that the notes would be cleaner and could be wiped clean if they became wet.

A Bank of England spokeswoman said: "We have not tested polymer banknotes with cocaine."

The tests Bank officials have done have focused on more mundane things like "testing them in a washing machine", the spokewoman added.