Fighting Fashion Fraud…. with DNA and Lasers

We’ve all seen them. Fake Rolex watches, Prada handbags and Ralph Lauren shirts, adorning market stalls the world over. But did you know that pirated and counterfeit goods are estimated to cost businesses more than £161 billion every year ?

fake-handbags

Counterfeiting designer goods might sound like a crime that DOES pay, but is one that many governments are publicly clamping down on. From burning a pile of counterfeit good in China, to an announcement from the UK’s Intellectual Property Office that if found guilty, offenders could spend up to 10 years in prison, its clear that counterfeiting continues to hit headlines.

Police destroy 200m Yuan worth of counterfeit goods, Guiyang, Guizhou Province, China - 14 May 2013

But even before counterfeit goods are manufactured, and the fake designer logos applied, a crime may have already been committed. As the demand for luxury fabrics like tweed and merino wool grows, especially in the Far East, textile counterfeiting is fast becoming the norm. In 2012, it was estimated that counterfeit wool had cost Australian wool growers a staggering £37.5 million. Chocolate Fish – a company who make outdoor clothing from New Zealand merino wool – say that counterfeit merino is everywhere – “…there aren’t enough merino sheep producing superfine fleece in Australia, New Zealand and China combined to supply all that’s coming out of China labelled (as) merino.”

This increase in demand has led to some good news stories – artisan craftsmen are starting to benefit from this fashion-industry-led heritage textile resurgence. Japan has become the biggest market for Harris Tweed, with the country snapping up ~40 % of the products exported from the Scottish group of islands. And in Donegal, Ireland, another famous bastion of tweed production, the story is very similar, with a growing interest from the Asian market.

tweed sleeves

So, this all got me thinking – how can you check that any tweed you buy is the real stuff? How can you differentiate between a fabric which is 100% wool, and one that is synthetic (or a synthetic blend)?

I’m sure that any textile expert could tell you by feel alone,  but I went on the hunt for some high-tech methods to identify counterfeit textiles

1. The burn test: This came up time and again – it involves taking a snippet of the fabric, setting it alight, and watching how it responds. If it is a wool, it will char and smell like burnt hair, but it won’t fully ignite. If any synthetic fibres are present, the fabric will burn quickly, and may melt or drip. So, it should be easy to distinguish between natural and synthetic fibres, but it seems a little basic, and is obviously destructive, which may not be an option for customs officers or concerned customers.

2. DNA marking: While googling, I found a company called  Applied DNA Sciences Inc – APDN. Their site says:

“SigNature® DNA and smartDNA, our principal anti-counterfeiting and product authentication solutions that essentially cannot be copied, provide a forensic chain of evidence and can be used to prosecute perpetrators.”

DNA-marking fabric is a fantastic idea. The chain of (plant) DNA cannot be copied, shows impressive stability even in harsh environments, and can be applied to the fabric at any stage of the manufacturing process. So you can see how this would be extremely useful in the most serious of fraud cases. But practically, this technique sounds pretty complex. The DNA marker can only be identified by the company that applied it. Now this certainly provides excellent traceability to the process. But it also probably means that a customs officer cann’t get an immediate result – it couldn’t be used to quickly determine if a roll of textile is genuine.

3. Terahertz laser spectroscopy: Now I must admit, I didn’t have to go very far to find out about this technique – this work is being led by a John Molloy, friend and ex-colleague of mine from NPL. The theory is quite straightforward – different types of fibres display different optical properties (in the terahertz range). By knowing the terahertz response of a range of textile types, it is possible to identify which fibres are present within a sample.

Terahertz (THz ) radiation is often called “sub-millimetre”, as it falls between microwaves and infra-red light. The NPL system involves placing a sample of the textile within the beam of a terahertz laser. The individual fibres that make up the textile produce different rates of scattering and absorption of the THz  beam. If you know this response for a range of natural and synthetic fibres,  it would be possible, from the measured transmission profile,  to determine whether or not the fabric is counterfeit.

This THz laser system doesn’t just apply to wool. John and his colleagues also examined linen, cotton and silk and fabrics containing mixed fibres, all of which demonstrated distinct terahertz transmission properties. Their system is so sensitive that it can even differentiate between ‘standard’ and merino wool, as well as between natural and synthetic silk. Tests can be carried out quickly and safely, and the textile doesn’t suffer any damage from being illuminated in the beam.

Now, you may say that I am biased, but I think this is a fantastic project. It shows how fundamental science can be applicable to the outside world. It shows that research can have a positive impact on people’s quality of life. And it shows that most scientists really don’t want their work to stay in the lab – they want it out there, making a difference.

The story also has a lovely footnote that really demonstrates the interconnectedness of science and culture. John Molloy, one of the authors of this study, actually comes from a long line of weavers – five generations long, in fact. His father and brother run Molloy & Sons , a highly-respected producer of Donegal Tweed, famous for the specks of colour hidden within the weave. John is a physicist, in the midst of his PhD research on the terahertz properties of single-crystal topological insulators. By choosing a physics career, it may have looked like John was moving as far away from weaving as it is possible to get. But with this research, he has managed to tie those ends together. Not only is he providing a new tool in the war against counterfeiting, he is also helping preserve the unique craftsmanship involved in wool-weaving

MolloyAndSons(Image courtesy of Molloy & Sons)