Original URL: http://www.theregister.co.uk/2008/06/11/anton_wylie_phages/

Dissolving the plastic bag problem

The Phage Factor

By Anton Wylie

Posted in Science, 11th June 2008 12:02 GMT

Anton By rights the world and its dog should now know the name Daniel Burd. For Daniel Burd has an eco-friendly solution for disposing of the plastic bag menace. About half a trillion plastic bags are produced globally each year, but they take up to 1000 years to decompose. In the meantime they can migrate to the oceans and be ingested by wildlife, with fatal results.

Burd's discovery is bacteria which he reckons in combination can eliminate poly(ethyl)ene bags in about three months. The judges of the 2008 Canada-Wide Science Fair in Ottawa agreed, and awarded Burd top prize. You can read the report he presented ("Plastic not fanastic") here (pdf)].

Burd started with the idea that if plastic bags are being degraded by microorganisms in nature, it should be possible to isolate them. He collected soil samples from a local landfill site, and spent three months culturing them up on a diet exclusively of ground-up polythene bag. At this stage, he reasoned, if there were bacteria of interest, there should be enough of them to make a measurable difference. And so his experiments began.

The cultured broth was introduced to weighed amounts of polythene film strips, and the two were allowed to commerce for six weeks. Measure against a control sample of boiled broth which showed no change, the active samples showed a promising 17 per cent weight loss.

Burd then grew the broth on agar and found it contained four different types of bacteria. These he worked to separate, and tested them individually and in pairs for their polythene appetites. While one type of microbe showed a marked predilection for plastic bag, he also observed that a combination was even better at eliminating polythene. An identification kit enabled him to identify these as Sphingomonas and Pseudomonas types. Pseudomonas has been cited in previous research, but his discovery of the much more ravenous Sphingomonas, and the rest of his experiment, is new.

Further research by Burd on his microbe consortium, as his paper terms it, showed that their rate of digesting polythene was affected by temperature, population density, and by the level of concentration of added sodium acetate. He eventually achieved a stonking 42 per cent elimination of polythene in six weeks. On this basis, Burd projects that a complete dispersal of polythene is possible in under three months.

DIY decomposition

You can do this at home, folks, and you don't need lab equipment, or even to chop up the plastic bags. Burd is reported as having tried five or six whole bags in a bucket of his special goo, and the process worked just as well.

"All you need is a fermenter . . . your growth medium, your microbes and your plastic bags." said Burd. He points out that little energy is required as an input, as the microbes produce heat as they work, and they generate a meagre 0.01 per cent of their body mass as waste CO2. So we are unlikely to change the climate by helping nature's little helpers dispose of plastic bags the Burd way.

An impressive array of awards garnered by this nice piece of science at the Canada-Wide Science Fair is listed here, where it may be noted that among his many talents young Daniel can also write a mean CV.

Turning a new phage

There are resonances in this story of an earlier Canadian. Felix d'Herelle was a self-taught microbiologist, later nominated for a Nobel prize for his work on phages.

In 1919 d'Herelle isolated "phages", agents which were fatal to bacteria, and used them successfully to treat typhus in chickens, and dysentry in people. In 1939 electron microscopy confirmed them to be viruses.

Phage therapies began to be developed, but fell from favour in the West after the commercialization of antibiotics in the 1940s. But they are still used extensively in the countries of the former USSR and in eastern Europe.

d'Herelle had been invited in 1936 to co-found the Tbilisi Institute, Georgia (now the Georg Eliava Institute), and though he was associated with it only briefly it subsequently became the main world research and development centre for phage therapies. These have been applied to treating a large number of -itises (inflamations) and skin conditions, including chronic ones, and in post-operative care.

Phages have their attractions compared to antibiotics. The success rates are claimed to be comparable. As anti-microbial weapons, they are precision bombers, in comparison to antibiotics which tend to nuke everything. They have few if any side effects, and need only small doses to work. R&D is crucially not capital or IT intensive - the Tbilisi Institute would send for samples of river water to be hauled up in jars. With increasing antibiotic resistance stemming from their widespread use now beginning to cause problems, phage therapy is seen by proponents as an option.

Yet here, in drawing a parallel with Daniel Burd's ambition to see his discovery in large-scale use, the story of phage therapy gives pause for thought. Despite access now to decades of research, in the West funding for phage research continues to be scant. Potential investors have to square up to the gorilla that is intellectual and property rights in the legal/patents ring.

In addition regulators such as the FDA maintain that each and every phage of a therapeutic combination must separately pass scrutiny. But they clearly recognize that prescribing physicans have resorted to combination antibiotics at their discretion, and that administering a herbal remedy, regardless of efficacy, necessarily entails taking a cocktail of pharmacologically active ingredients. (Not to mention GM foods).

We note Daniel is an accomplished pianist with an interest in jazz improvisation, and hope that the comparison with Felix d'Herelle does not dissuade him from pursuing a scientific career. But if science's loss were to become music's gain then in 10 years time it may become clear that a different analogy should have been drawn here, one perhaps with Keith Jarrett.

So why haven't we heard of Daniel Burd?

Science and the consensus

The breakthrough first aired in the May 22, 2008 edition of the Ontario Record (audited circulation 6 months to March 31, 2006 of 73,852). It never made the BBC, which instead on June 1 chose to lead with the ban on thin plastic bags in China, a story it had covered in early January, when the People's Republic announced its intentions. A search of the online presence of the UK's national dailies for Daniel Burd also draws blanks.

Perhaps it is because Burd is not a tenured professor, and is not supported by a long list of citations and a vociferous "consensus". Indeed, he does not even have a graduate degree. He is only 16. On the other hand he has the imprimatur of science. One suspects the BBC of 2008 of being unable to pass up opportunity to broadcast to its home audience the message that it is too dilatory over saving the planet. ®