Tuesday, 23 September 2014

Hidden Hunger in Malawi...by Edward Joy

Edward in his panama hat out in Malawi
A few months back we shared a great post about the award winning PhD student (working at BGS and University of Nottingham) Edward Joy, whose project tackles the important issue of hidden hunger in Malawi. Now Edward tells us in his own words about his research and years of research in the field...

The last couple of years have been a steep learning curve for me: a faulty radiator can write off your engine; laptop battery life is everything; and you may need to hire guards to keep monkeys off your maize trials! These have been valuable lessons as I plan to continue similar research in Ethiopia starting in December. Overall, it has been a pleasure living in Malawi, a country endowed with some very beautiful landscapes and incredibly friendly folk – it’s not uncommon on sampling trips to be invited into farmers’ houses for roast pumpkin and peanuts.

My project aim, using cross disciplinary science, is to improve the accuracy and spatial resolution of dietary mineral supply estimates in Malawi and to investigate the potential of agricultural solutions to mitigate dietary mineral deficiencies.  The Malawi Ministries of Agriculture and Health have been very supportive and hopefully the outputs will be useful to them, for example in developing fertiliser policies and targeting nutrition strategies.

So here's a look in more detail at the work I've been doing out in Malawi...

Hidden hunger

Humans require 22 mineral elements for their wellbeing including calcium (Ca), iron (Fe), magnesium (Mg), selenium (Se) and zinc (Zn). The biological functions of elements include bone structure (Ca and Mg) and, as constituents of proteins, immune response (Se and Zn) and oxygen transport (Fe and Zn). Adequate quantities of these elements in diets is thus necessary for food security; inadequate intakes, or poor absorption in the gut due to e.g. diarrhoea, can lead to ‘hidden hunger’. It’s termed ‘hidden’ because the physical effects are not obvious, unlike the symptoms of protein or energy undernourishment, and because it is often hard to quantify the prevalence of such malnourishment in populations.

Dried fish at a market in the capital city, Lilongwe
Malawi hasn’t witnessed widespread famine since 2005, although certain regions are prone to food shortages due to both drought and flooding. But it may be that hidden hunger is widespread and that deficiencies of certain minerals and vitamins are a major health burden. There is evidence to suggest this is the case, for example with Se deficiency (Gibson 2011; Eick 2009; Hurst 2013) and Zn deficiency (Gibson1998; Siyame 2013); but there is no data at the national level.

Element concentrations

Malawi is predominantly a subsistence economy in which households grow their own food. The dietary supply of elements is thus dependent on which crops households choose to grow and what those crops contain. Element concentrations in crops depend on the availability of elements in the soil: for example, in low-pH soils Se is predominantly found in forms unavailable for plant uptake, whereas in soils with pH >6.5 Se is generally soluble, mobile and readily available for plant uptake.  There are limited data on crop composition in Malawi so we worked to fill this gap, collecting over 600 crop samples representing 97 food items for multi-element analysis by ICP-MS (Joy et al. 2014). We found that soil type affects crop composition, with maize and leafy vegetables from calcareous soils having greater Ca, Cu, Fe, Mg and Se concentrations than those grown on non-calcareous soils. Maize also had greater Zn in samples from calcareous soils, whereas leafy vegetables had greater Zn from non-calcareous soils.

The household survey

Edward presenting the team’s work at Mzuzu University
in northern Malawi
To find out what crops households are growing and what foods they are eating, the Malawi Household Survey (World Bank and Malawi Government) has proved a valuable resource. In this survey, >12,500 households were asked what foods they consumed over the last seven days. We are working to match this data to our composition data to generate dietary mineral supply estimates by region and soil type. One of our early findings is the critical importance of small fish in meeting Ca, Se and Zn requirements. Most fish production is from Lake Malawi, a Rift Valley lake that runs much of the length of the country. It’s sometimes known as the Calendar Lake as it’s roughly 365 mile long and 52 miles wide. Fish are sundried before traders take them inland. Although fish is a vital source of minerals in the diet, households require some cash to purchase them. It will be very interesting to see the relationship between household income and consumption of fish.
 The FAO and World Bank have just published a book called ‘Analyzing Food Security Using Household Survey Data and at the recent Micronutrient Forum held in Addis Ababa, Ethiopia, I found that other research groups including IFPRI are doing similar work to us. It’s great to see the hard work now contributing to scientific knowledge as we write up, publish and present our findings.

Thanks for reading

Here are my references:

Eick F, Maleta K, Govasmark E, Duttaroy AK, Bjune AG (2009) Food intake of selenium and sulphur amino acids in tuberculosis patients and healthy adults in Malawi. Int J Tuberc Lung Dis 13: 1313–1315

Gibson RS, Bailey KB, Ampong Romano AB, Thomson CD (2011) Plasma selenium concentrations in pregnant women in two countries with contrasting soil selenium levels. J Trace Elem Med Bio 25:230–235

Gibson RS, Huddle JM (1998) Suboptimal zinc status in pregnant Malawian women: its association with low intakes of poorly available zinc, frequent reproductive cycling, and malaria. Am J Clin Nutr 67:702–709

Hurst R, Siyame EWP, Young SD, Chilimba ADC, Joy EJM, Black CR, Ander EL, Watts MJ, Chilima B, Gondwe J, Kang’ombe D, Stein AJ, Fairweather-Tait SJ, Gibson RS, Kalimbira AA, Broadley MR (2013) Soil-type influences human selenium status and underlies widespread selenium deficiency risks in Malawi. Sci Rep 3: 1425. DOI: 10.1038/srep01425
Joy, EJM, Broadley, MR, Young, SD, Black CR, Chilimba, ADC, Ander, EL, Barlow, TS and Watts, MJ*. (2014). A spatially refined food composition table for Malawi, Science Total Environment, (accepted Sept. 2014)

Siyame EWP, Hurst R, Wawer AA, Young SD, Broadley MR, Chilimba ADC, Ander EL, Watts MJ, Chilima B, Gondwe J, Kang'ombe D, Kalimbira A, Fairweather-Tait SJ, Bailey KB, Gibson RS (2013) A high prevalence of zinc- but not iron-deficiency among women in rural Malawi: a cross-sectional study. Int J Vitam Nutr Res 83: 176–187

Friday, 19 September 2014

One of our ecological footprints… By Sarah Bennett

Landfills provide a way of hiding away the rubbish we create – out of sight out of mind.  However, research now shows that chemicals leaching from these landfills are polluting our rivers.  The work led by BGS scientist, Daren Gooddy, found that approximately 27.5 tonnes of ammonium a year finds its way from unlined landfills on the outskirts of Oxford, through a flood plain and into the River Thames. Here Sarah Bennett, a Stable Isotope Research Geochemist at BGS and co-author of the research, explains more...
Once ammonium enters the rivers, it breaks down to nitrogen.  The extra nitrogen can trigger excessive plant growth and decay, damaging water quality and starving fish and other aquatic organisms of the oxygen they need to survive.  Scientists are most worried about so-called blue-green algal blooms, which can produce toxins capable of killing wild animals, livestock and domestic pets.  In people, they can cause skin rashes, nausea, stomach pains, headache and fever.
Sampling groundwater on a floodplain in the winter is not always
      straight forward and requires both innovation and improvisation    
The source of the ammonium was identified with isotopes, a chemical fingerprinting technique, and this enabled the team to attribute the ammonium to household waste.  This isn’t the first time isotopes have been used to identify human impacts on the planet.  Back in August, Jonathan Dean discussed how isotopes provide evidence of human activities 2000 years ago during mining and smelting and more recently during the industrial revolution.  His work suggests that we are in a new geological age, the Anthropocene: where humans impact and change the environment (read Jonathan's blog here).

Aerial view of Port Meadow, Oxford, during flooding
As a society we are concerned with our current and future activities on this planet, but we also need to deal with the ramifications of our past mistakes.  These landfills are one such example; we’ve learnt to line our landfills with thick clay to prevent chemical leaching, but we still need to deal with the unlined landfills that represent thousands of historic landfills across the UK.  We’ll be drawing up new management plans for floodplains on the margins of towns and cities as a result of this work. 

You can read more about this research in the journal Science of the Total Environment.


Tuesday, 16 September 2014

Rob Ward - a Groundwater Guru... by Hazel Gibson

Hi, I’m Hazel Gibson, a PhD researcher from Plymouth University, who is interested in what people think about geology and how that affects how we as geoscientists communicate it. During July I was up at the British Geological Survey speaking to the scientists about their work, what makes them passionate about it and why they think it’s important to us. The following is a series of short 'people posts' about the real faces behind the BGS.

Dr Rob Ward with the amazing sand tank groundwater model.
Dr Rob Ward has one of the most challenging jobs in the BGS. As the Director of Groundwater Science, he oversees a huge research department examining all aspects of groundwater use in the UK and abroad and he also acts as a liaison between his research teams and a diverse range of other government bodies. He is, in many ways, the ‘face’ of groundwater research at the BGS and is very proud of the diverse team that he manages and the exciting work that they are doing. He started his career at the University of East Anglia in Norwich, studying Environmental Science and majoring in Aquatic and Atmospheric Science.

When he finished his degree, he decided to pursue a PhD and focused on the chalk aquifer,  one of the most important sources of drinking water in the UK and which maintains the flow in many of the rivers in southern England. He enjoyed his PhD so much that he wanted to stay working in the same field, so joined the BGS in, what was at the time called, the Fluid Processes Research Group.

He stayed at the BGS for 10 years, examining subjects as diverse as landfill gas migration and radioactive waste disposal, before being selected as the first of a new cohort of exchange workers, sent to the Environment Agency to improve communication and understanding between the different science organisations (a practice that continues today). Unfortunately for the BGS, he enjoyed the challenges of working for a new team, within a different organisation so much that he wanted to stay. “I enjoyed working there so much that I tried to make myself invaluable. If you do that then you’ll have a lot more options at the end of your secondment!” He was successful and ended up staying with the Environment Agency for 12 years commissioning or appointing research; translating its results into policy and operational guidance; and providing advice to government departments like DEFRA. He gradually started to move from research to policy, handling many of the new EU requirements for more robust planning and management of risks to groundwater. He also had the challenge of managing a large dispersed project team comprising people that he didn’t directly manage. The aim of this group was to develop and implement a new national monitoring strategy for UK groundwater.

Rob was faced with the question of 'how do you meet complex and difficult targets with people who don’t answer to you?' The answer he says is trust. “I had to build trust with the people who I needed to do this work whilst at the same time getting buy-in from their managers. It was great experience for me.”

About four years ago, Rob was given the opportunity to become the Head (now Director) of Groundwater Science, back in the BGS and he says he doesn’t think he could have got to this position  without broadening his experience outside the Survey. Now he is in charge of a department that is at the heart of many issues faced in the UK today, from natural groundwater chemistry to cutting edge 3Dgroundwater mapping, from resilience of our water supplies to climate change, to the legacy of our industrial past. These issues impact us all in many ways and our lack of awareness of this problem is part of a bigger issue that Rob and his whole department are trying to fix. “Here in the UK, we don’t recognise how important groundwater is – it’s hidden. Out of sight, out of mind.” In order to raise awareness of this precious resource, Rob is a strong advocate for public engagement and encourages his team to discuss their work with others. He even demonstrated a great new piece of kit that simulates groundwater flow in different environments – the Sand Tank Model. This model allows people to manipulate the groundwater movement through an aquifer and introduce coloured dyes to simulate groundwater contamination and flow through different types of ‘rock’ and at different depths to see how they interact. It’s a brilliant example of making the unseen, seen and understandable.

The Groundwater Science team also help produce the
Hydrological Outlook - this is for August 2014.
But for Rob, communicating his science doesn’t just mean sand tanks and school children. At the height of the Somerset floods (winter2013/14), Rob was called to Downing Street to represent the BGS, as a part of SAGE (the Scientific Advisory Group for Emergencies) to advise the Prime Minister and the government about the flooding crisis unfolding across the south of England. Rob’s position means that he has to be ready at any moment to speak with the national media, the government or a member of the public about the risks and opportunities provided by UK groundwater. It’s a difficult job, but with the support of his team, Dr Rob Ward is confident he can improve our understanding and awareness of groundwater in the UK, and I think so too.