Interviewer: Lucy Vernall (Project Director, Ideas Lab)
Guest:  Dr Joanna Renshaw
Recorded: 25/05/2011
Broadcast: 30/05/2011

Intro VO: Welcome to the Ideas Lab Predictor Podcast from the University of Birmingham. In each edition we hear from an expert in a different field, who gives us insider information on key trends, upcoming events, and what they think the near future holds.

Lucy: Today we’re joined by Dr Jo Renshaw who is Lecturer in Biogeochemistry at the University of Birmingham.   Welcome Jo.

Jo: Thank you.

Lucy: Tell us about biogeochemistry and what it is that you do.

Jo:  Well I work here at Birmingham in the Water Sciences group and one of the areas we’re interested in is the spread of contaminants in the environment and the restoration or remediation of those environments.  But what I’m particularly interested in is microbial transformations and interactions with environmental contaminants, especially radioactive contaminants but also metals and organics and new contaminants such as nanoparticles.

Lucy: So we’re talking about how things like bacteria and fungi can alter the contamination in things like our water.

Jo: Yes, exactly. Microbes such as bacteria and fungi can affect the environmental behaviour and chemistry of contaminants and we’re interested in this for several reasons.  One is if we want to understand and predict the spread of contamination and assess the risks from the contamination and develop remediation strategies, we need to understand how all the components of that environment are going to affect the contaminant.  So how the rocks, the minerals present will affect the contaminant and how the geochemistry of the ground water will affect it and how the microbes present and the reactions that they can cause will affect the contaminants.   And we’re also interested in how we can possibly exploit the reactions that these microbes perform to develop new remediation methods to treat contaminated lands or waters for example or to treat waste waters from industrial processes to prevent contamination.  So looking at perhaps more efficient or less energy intensive clean-up methods.

Lucy: So microbes can actually clean up even radioactivity?

Jo: Well, if you take the example of chromium. Chromium’s a metal contaminant and it’s an interesting example of how microbes can affect the behaviour of the contaminant in the environment.

Lucy: So chromium’s the thing that was made famous by the Erin Brokovich case.

Jo: Yes. As chromium 6 in the environment that’s carcinogenic, it’s very soluble and so it’s very mobile in the environment and very bioavailable. It’s relatively easily taken up into the food chain.  Now, microbes can change chromium 6 to chromium 3 and chromium 3 is not carcinogenic, it tends to be insoluble and so will not spread as far as a hexavalant chromium and so it’s far less problematic.   So we’re interested in other ways you can kind of encourage naturally occurring microbes to, say, perform that reaction to limit chromium migration.  

Lucy: So presumably microbes could be of great use when we’re looking at sites like, for example, our nuclear sites that we’re having to clear up.

Jo: Oh yes, yes.

Lucy: At the moment before we build some new ones.  

Jo: The nuclear side of things is one of the most important challenges that we’ve got facing us in this country. We’ve had sixty years of nuclear energy programmes, nuclear weapons programmes and a sixty year history legacy of waste and contamination and it’s recognised really that we have to deal with that legacy, particularly if we embark on a new nuclear build programme.

Lucy: Yep.

Jo:  So we have to have ways of dealing with the old waste that we’ve got before we start creating new. And the nuclear clean-up of our sites from the most important and demanding environmental and technical challenges that we’re facing in the UK over the next century.  Now we’re currently working on a project with collaborators at the Sellafield site which is the most complex nuclear site in Europe.  Decommissioning and clean-up costs are estimated at around £32 billion by the NDA [Nuclear Decommissioning Authority] at this site and what we’re interested in with our collaborators at the Sellafield site is: we have a source of contaminants, understanding what are the ecosystems or receptors vulnerable to these contaminants and how the contamination is going to spread in that Sellafield site.  So fully understanding the pathway from your source to your receptor.   

Lucy: Because there have been leaks from Sellafield and those leaks have reached beaches and water elsewhere.

Jo:  Yes, yes.  I mean the Sellafield site is on a coast, there’s a river running through the site, there’s a river at the edge of the site near the coast and there’s springs coming up on the beach and they’ve detected low levels but radioactive material at the beaches and the springs.  What we’re interested in is fully understanding what’s happening beneath the Sellafield site and so a radioactive element called Technetium which behaves in a very similar way to the example I gave with chromium, in all chemical forms it’s radioactive but in one particular chemical form it tends to be more bioavailable and more mobile in the environment but again, microbes can transform it to a form which is less mobile and less bioavailable.  So again, that’s looking at is that a reaction that we can encourage in the environment that will help to limit technetium spreading?

Lucy: A lot of what you’re doing is looking ahead quite a long way.  I know one thing that’s on the horizon is the EU Water Framework Directive and implementing improvements in our water and that you’re feeding into that.

Jo:  Yes.   This is EU legislation that aims to protect and enhance the quality of surface waters, ground waters, estuaries and associated systems.  So basically trying to improve the quality of our water systems.  And in the UK it’s the Environment Agency that are responsible for implementing this Water Framework Directive and the stage we’re at now is that they’ve kind of assessed the water systems within the UK in terms of what are the risks associated with them from our legacy of contamination, what are the challenges there and they’re now at the stage of they’ve developed plans for the different water systems setting environmental objectives and standards that we need to try and meet for these systems and as we implement these plans there’s going to be challenges to meeting these objectives and standards.

Lucy: As well as looking at radioactive elements you’ve also been looking a little bit at viruses that might be in the water as well.

Jo: A lot of my interest has been in kind of how microbes affect other contaminants but we’ve also been looking at the microbes themselves as contaminants. In particular, looking at viruses and what factors can affect virus transport in the environment.

Lucy: These are viruses that are kind of leaching out of landfill for example or sewage?

Jo:  Yes.  With viruses, or bacteria for example as well, anything that’s a human pathogen, the important thing is not so much how far it migrates but whether it can still cause an infection when it gets there.  But studies undertaken at the University of Sheffield, we’ve been collaborating with them on this, have shown that you can get viable pathogens capable of causing disease spreading quite far away from landfill sites and so that’s a problem.  What we’ve been looking at here at the University of Birmingham is trying to understand how far viruses can spread and the processes controlling their spread and particularly controlling their viability when they get from A to B. Are they still viable when they get to the end and are still capable, if it’s a human pathogen, of causing disease? Now, clearly we’ve not been working in our experiments with human pathogens, we’ve been using viruses known as bacteria phages so we can grow up these viruses in a particular bacterium and we’ve been injecting them down bore holes on campus, so you inject them down one bore hole and see where they appear in another bore hole and one of the things that my colleagues have been investigating particularly is looking at the geology of those systems, so the particular pathways that your viruses can migrate from A to B.  So it can depend a lot on the geology. Have you got particular rocks that your viruses will stick to or particular sections of rock which are more permeable for example where you get more ground water flowing through because then you’d expect that to be more of a substantial pathway for the viruses to migrate through.

Lucy: On the slightly brighter side of future developments are the things that micro-organisms could do for us.

Jo: Yes.

Lucy: And you also look at those as well.

Jo: Yes.  Can you use these microbial reactions to turn, say, wastes into a resource? One of the projects I’m involved with with colleagues in Civil Engineering is looking at anaerobic digesters. These are a way of treating waste water sludges, whether it’s from industrial processes or domestic waste, and microbes will break down this material and in doing so the microbes can make biogas, can make methane, and this is a resource that can be used for energy production.  And one of the things we’re interested in looking at is how to optimise conditions within these anaerobic digesters to maximize biogas production. So as well as treating the waste you are producing something which can be used to generate energy. Looking to the future, one of the issues is going to be rare earth elements. The European Commission has identified these rare earth elements as potentially critical for the EU economy.

Lucy: So rare earth elements are basically?

Jo: Well, the names probably won’t mean much but things like neodynium, gadolinium but they are critical in electronics components and lots of kind of high tech industries.

Lucy: And we don’t have a lot of them in the UK?

Jo:  No, or the EU in general.  China is the predominant supplier now. They control 95% of production and also around 60% of consumption so as with a lot of other resources there are issues where diminishing resources are concentrated in the hands of particular countries so they have power of supply.

Lucy: Yeah, yeah.

Jo: And this has been recognised as a problem by the EU. The next stage will be to look at how can we ensure continuity of supply for these critical elements?  One way of looking at that is more recycling.  Can microbes help develop more efficient ways of extracting these metals from waste materials from all those electronic components which are going to landfill or for reuse.

Lucy: So hopefully in the future your research will mean we’ll have more biogas, cleaner water, cleaner nuclear sites.

Jo: Yes, hopefully!

Lucy: And more rare earth elements as well.

Jo: Yes.

Lucy: Jo Renshaw, thank you very much.

Jo:  Thank you.

Outro VO: This podcast and others in the series are available on the Ideas Lab website: On the website, you can find out how to e-mail us with comments, questions or suggestions for future topics for the podcast. There's also information on the free support Ideas Lab has to offer to TV and radio producers, new media producers and journalists. The interviewer for the Ideas Lab Predictor Podcast was Lucy Vernall, and the producer was Andy Tootell.