On a BBC radio 5 program in the first week of July, controversy arose over a recommendation to drink lots of fluids and to avoid tea… because it dehydrates. Many listeners called in to refute this, and the programme heard from a UK expert whose work had refuted this fallacy completely ¹. Yes, the caffeine in the tea will dehydrate you, but there is not enough caffeine in your average cup of tea to outweigh all that fluid you drink along with it. You also have the added bonus of flavanoids, which have protective effects for some heart disease and cancers, fluoride for teeth and components with antiviral activity.

So I have searched the Global Health database to pull out some useful information for you on the protective effects of tea flavanoids ^2-5 and tea antiviral activity ^6-7.

References

1. Black tea – helpful or harmful? A review of the evidence. Gardner, E. J. et al. Eur.J. Clinical Nutrition (2007) 61, 3–18.
2. Construction of a flavonoid database for assessing intake in a population-based sample of women on Long Island, New York. Fink, B. N. et al Nutrition and Cancer (2006) 56 1 57-66
3. Chemoprevention of human prostate cancer by oral administration of green tea catechins: a translational research story. Bettuzzi, S & Rizzi, F. Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Agriculture (2008) 65, 1, p.29. FULLTEXT available to Global Health subscribers   
    
4. Protective effect of green tea against prostate cancer: a case-control study in Southeast China.
   Jian Le et al. International Journal of Cancer (2004) 108, 1, 130-135
   
5. Possible protective effect of green tea intake on risk of adult leukaemia. Zhang, M. et al. British Journal of Cancer (2008) 98, 168–170. (Full abstract available to Global Health subscribers)
6. Antibacterial and antiviral effects of tea - from influenza to SARS. Book chapter. Jain, N. K et al in Protective effects of tea on human health, 2006. Editor: Leung PingChung
7. Gargling with tea catechin extracts for the prevention of influenza infection in elderly nursing home residents: a prospective clinical study.Yamada, H. et al. J. Alternative and Complementary Medicine (2006)12, 7, 669-672.

.

The Argentine Post points out that Argentina is now entering its winter, and that the “number of cases stand at 1587 and deaths at 26 (June 26)”. For June 29, the WHO states that laboratory confirmed cumulative cases and deaths are 1488 and 23, so I think the writer of the Post piece added cumulative numbers to the newly reported ones for June 26.

Be that as it may, the WHO figures put Argentina 7th in global rank of number of cases (USA and Mexico are 1 and 2) and 3rd in number of deaths (Colombia and Mexico are 1 and 2). Experts tell us that influenza is a virus that prefers the winter season in temperate regions… though it must be a considerably warmer winter in Argentina compared to the UK.

There are other figures in the Argentine Post piece - death rates calculated for Argentina, Chile and Mexico but they forgot to convert their figures correctly to get %. By my calculations, the true figure for death rate in Argentina is 1.6% (not 0.016%!), which means it is experiencing a similar death rate from this strain of flu to that of Mexico (1.4%). Only Colombia (2.7%) outdoes these two countries for death rate from this flu strain, though it has less than a hundred confirmed cases.

No wonder a health minister in Argentina, faced with figures like this and the general belief that the case numbers were actually far worse, resigned…

Why are Argentina, Chile & Colombia so hard hit? Its worth considering how they fare with seasonal influenza. According to PAHO, in 1999, the death rate for children under 5 years from pneumonia and influenza was 3.6% (Argentina), 1.3% (Chile) and 10.8% (Colombia). This compares to 1.4% for the USA in 1999. All three countries run vaccination campaigns for infants and the elderly, but Colombia only introduced theirs in 2005.  You can see from these figures that Colombians are in general more susceptible to influenza…whether this is due to lack of access to healthcare or genetics (viral or human), I cannot say.

AS of July 2 2009, the Argentine government is in full disease prevention mode. All pregnant women are being given 2 weeks leave from work immediately, free treatment is offered for those with symptoms whatever their insurance status, TV programs are educating the public in how to hand-wash correctly, make face masks, and how to greet people without hugs and handshakes...use a formal Japanese style bow!

Here in the UK, its serious enough to issue advice to schools to pass onto parents but there is no panic.

The advice includes to sneeze into paper tissues, discard immediately, then wash your hands ...BUT meanwhile all these possibly infected tissues will be sitting in the communal bins in offices, on the street or festering away in the fortnightly recyclable waste bin...or should used tissues not be recycled?  How long does this type of envelope virus remain viable? I have an answer..it depends on absolute humidity and on the presence of nasal mucus. Influenza viruses, in the presence of nasal mucus, can survive for up to 48 hours on banknotes (!)(1): other studies suggest only 6-8 hours on metal surfaces and just 15 minutes on a tissue but I believe these tested pure viral cultures. Having the mucus there prolonged survival in a third of samples to 48 hours. Low absolute humidity favours both survival and transmission(2)...which is why flu outbreaks occur in winter.

Will dustmen start wearing facemasks? What about all those trees fated to end up as paper tissues? Is there a bin which comes with disinfectant spray which treats the tissues on a regular basis? Those of us who have worked in laboratories, remember the bins of diluted bleach or disinfectant on hand to disinfect used pipettes, but health & safety out in the normal world dictates it will have to be more sophisticated than that.

Lets enter the world of Global Health and see what we can find out about influenza outbreaks in Latin America and some answers to how the individual can reduce transmission (apart from staying at home).

References

1. Survival of influenza virus on banknotes.  Thomas Y. et al. Applied and Environmental Microbiology (2008), 74, 10, 3002-3007
2. Absolute humidity modulates influenza survival, transmission, and seasonality. Shamani J. & Kohnb, M. PNAS (2009)early edition DOI: 10.1073/pnas.0806852106
3. Epidemiological study of influenza virus infections in young adult outpatients from Buenos Aires, Argentina  Santamaría, C. et al. J. Influenza and other Respiratory Viruses 2008 Vol. 2 No. 4 pp. 131-134
4. School closure to reduce influenza transmission. Koonin, L.. M. & Cetron, M. S. ,Emerging Infectious Diseases (2009), 15, 1, 137-138, correspondence (links to Global Health, subscribers only)

An extract from the public presentation, by Prof. J.E.N. Veron, with an introduction by Sir David Attenborough, which took place Monday afternoon at the Royal Society, London. I attended the presentation, which was followed by a summary of a statement produced by the technical expert workshop held in the morning. Above is a photo I took during the event questions session, showing Sir David Attenborough on the left and Prof. Veron on the right.

In his introduction to the presentation Sir David Attenborough started by saying ‘we all think we know coral reefs, we have seen it on the telly.’ He introduced Prof. Veron, who he said has the best job in the world - swimming and studying the most beautiful reefs in the world and pointed out he produced the definitive catalogue of reefs in the world. During his research life he discovered that coral reefs are dying and that things will get worse as CO₂ emissions increase. Sir David ended his introduction by saying we hear a lot about the impact of global warming on the environment second hand in the media, but today we are privileged to hear about coral reefs first hand from the world’s authority on coral reefs.

Prof Veron started the presentation entitled ‘Is the Great Barrier Reef on Death Row’ with a background on corals. Coral reefs are unique. They exist at an interface of the atmosphere and the ocean. They are geological structures very closely attuned to their environment and they are very particular about light, temperature and carbonate chemistry of the ocean. Reefs are nature’s historians; they are made of limestone and so are preserved in fossils; every fossil is a book of the environment that existed.

He also discussed the history of coral reefs mass extinction from the Ordovian, millions of years ago, to today, showing that extinction happened in each era and the reefs managed to reform themselves. Carbon dioxide concentrations in the atmosphere went up and down over each era, but only now it has been linked to coral reefs mass extinction, which coincided with periods of high CO₂ in the atmosphere. However, corals are very good at recovering from mass bleaching in a matter of a few months (from rubble to reef), but only if the water quality in their environment is good.

Bleaching started happening recently in the early 1980s and the effects increase with increased CO₂ concentration in the atmosphere, since the oceans absorb 1/3 of the CO₂ we produce. The effects of increasing CO₂ concentration on coral reefs were shown and are as follow:

• 320 ppm  - not much effect
• 350 ppm - periodic bleaching
• 387 ppm (current level) - compound long-term degradation
• 400 ppm (target for year 2015) - will cause severe bleaching
• 450 ppm - severe bleaching most years
• 500 ppm - will cause bleaching every year, if there are any coral reefs left.
  

The morning technical workshop meeting group, which included marine scientists and climate change experts produced a statement, which concluded that at today’s CO₂ levels of 387 ppm reefs are seriously declining. Proposals to limit CO₂ levels to 450 ppm will not prevent catastrophic loss of corals, and other human impacts will prevent coral reefs from recovering. This is just a brief summary of the statement, which contains many more recommendations in more detail.

This link to the statement was just emailed to me by Prof. Veron, as I was writing this blog.

All the participants of the workshop and the presentation audience signed the statement, which is going to be sent to Copenhagen before the December meeting of the UNFCCC and Kyoto protocol parties.

Many other ocean life forms are affected by mass bleaching, but it’s only the coral habitat that is lost. Coral reefs loss will also result in large economic losses from tourism and, more importantly, a loss to a large section of the population mainly in developing countries, who depended on coral reefs for food and their livelihoods. 

Link to Prof. Veron’s research site: Coral Reefs and Climate Change

A public presentation at the Royal Society, with introduction by Sir David Attenborough. Read on to find out the details.

Coral Reefs are said to be the "Rainforests" of the ocean. Reefs are ecologically important ecosystems and have a high biodiversity that serves as a storage bank of rich genetic resources. They are a source of food and medicine, and they protect the coast from wave erosion. 

Coral reefs are directly impacted by the synergistic effects of global warming and ocean acidification and are likely to be placed into a situation of irreversible decline if immediate steps are not taken to reduce CO2 emissions. In December 2009, parties of the United Nations Framework Convention on Climate Change (UNFCCC) will be meeting in Copenhagen, Denmark, to discuss and hopefully agree to greenhouse gases emission reduction targets. The scientific community has a critical role to play in informing the decision makers involved in the UNFCCC talks about the level of greenhouse gas emissions cuts required to avoid the most severe impacts of climate change and ocean acidification. To highlight the danger of a major collapse of this ecosystem and the action which needs to be taken in Copenhagen, an event was organised by the International Programme on the State of the Ocean, the Royal Society, and the Zoological Society of London. 

The presentation is taking place today (Monday 6th July 2009) from 3.30 to 5 pm and will be delivered by Professor J.E.N. Veron, a former scientist from the Australian Institute of Marine Science and widely regarded as the world’s leading authority on coral reef ecosystems. He has extensively researched the highly synergistic threats posed to coral reef ecosystems by global warming and ocean acidification. Professor Veron will summarise these threats and the action he believes is essential at Copenhagen this December.

The introduction to the presentation will be given by Sir David Attenborough, and therefore should be well attended. I will be attending the presentation, in my capacity as co-editor of Cabi’s Environmental Impact database.

Venue: The Royal Society, 6-9 Carlton House Terrace, London, SW1. (link to map)

Seats can be reserved by contacting aylin.mcnamara@zsl.org. Doors open 20 minutes before the presentation starts.

Photo credit: Wikipedia

A new study on greenhouse gas emissions associated with a nation’s consumption shows that high wealth seems to always result in high emission of carbon dioxide (CO₂) and other greenhouse gases. In a paper entitled ‘Carbon footprint of nations: a global trade-linked analysis’, Edgar Hertwich and Glen Peters investigated the carbon footprint for food, shelter, clothing, construction, mobility, the consumption of manufactured goods, services, and trade for 73 nations and 14 aggregate regions. The paper was published online in June 2009 in Environmental Science & Technology, the environmental science journal published by the American Chemical Society. Read on to find out how large economies, such as the USA, Japan, the UK and the poorest African nations perform.

The paper presents the first carbon footprint analysis of the most important economies of the world, such as the USA, which produces a large amount of CO₂ (28.6 tonnes CO₂ equivalent per person) and also of small nations, such as Malawi, which produce very little CO₂ footprint (0.7 tonnes CO₂ equivalent per person), using 2001 as the base year. The figure for the UK is 15.4 tonnes CO₂ equivalent per person.

There is a strong dependence of CO₂ emissions on wealth. The CO₂ emissions from fossil fuel burning and industrial processes increase by 81% with a doubling of per-capita expenditure. The emissions of other greenhouse gases, primarily methane and nitrous oxides, increases less strongly with wealth, by only 32%, because they are mostly associated with food production.

The analysis shows that the highest carbon footprint occurs in rich countries in North America (the U.S.A and Canada), Europe (Switzerland, Finland, the Netherlands), and Asia-Pacific (Australia), whereas the lowest occurs in African countries.

Food production is the most important cause of greenhouse gas emissions in poor countries, followed by household energy use, which is mostly for food preparation, hot water and heating.

Only very few, poor countries such as Bangladesh, Malawi and Mozambique have carbon footprints near the 1 ton per person required for all nations by 2050 in order to limit global warming to 2 ^oC. For most countries, the carbon footprint of food alone is around 1 ton per capita. I think it’s clear we can only achieve the 1 ton per capita if we really go back to basics and start living like people in Bangladesh and Malawi do. What are the chances of that happening???

By following this link the carbon footprint calculation tool can be accessed and national-level results can be found, including the importance of consumption categories and the carbon footprints of imports and exports.

The abstract of the paper can be found at http://pubs.acs.org/doi/abs/10.1021/es803496a.

The Environment Impact subset of the CAB Abstracts database contains close to 200 other records on carbon footprint.

Reference
Hertwich EG, Peters GP (2009). Carbon footprint of nations: a global trade-linked analysis. Environmental Science & Technology

Global climate change might force millions of people (some studies predict hundreds of millions) mainly in Africa and Asia, to leave their places over this century and to become "climate refugees". Political responses to this emerging problem do not yet exist, and the academic discourse on the issue has barely started. Prof. Frank Biermann, Head of the Department of Environmental Policy Analysis, Institute for Environmental Studies (IVM) VU University, Amsterdam, The Netherlands, and Ingrid Boas discussed the issue in an article entitled ‘Protecting climate refugees: the case for a global protocol’, published in Environment.

The Global Governance Project - a joint programme of 12 leading European research institutions - has set up a new initiative, the Climate Refugee Policy Forum. This forum is designed as a web-based clearinghouse, open for everyone, for up-to-date information on climate refugees and climate-related migration, including academic studies, policy papers, conference announcements, and links to key organizations active in the field.

The web page of the Climate Refugee Policy Forum is http://www.glogov.org/?pageid=80, where a significant amount of information and a comprehensive bibliography is downloadable from this website.

They welcome additional papers, literature references, conference announcements or other interesting material on climate refugees; you just need to contact the coordinator of the Climate Refugee Programme, Ingrid Boas, at Ingrid.Boas@ivm.vu.nl.

Reference

Frank Biermann and Ingrid Boas (2009) Protecting climate refugees: the case for a global protocol. Environment 50 (6):8-16.

Letters in BMJ today provide some useful reminders about using drugs to bring down fever in flu. They  are about non steroidal antiinflammatory drugs - these drugs include include aspirin, ibuprofen, diclofenac and mefenamic acid and are often the over-the-counter choice to reduce fevers. Until I read this I thought one could use them on flu.  But no....

The first letter from Rokuro Hama of the Japanese Institute of Pharmacovigilance reminds us there is evidence that NSAIDS can aggravate severe cases of flu.  Its also well known that salicylates (active ingredient in aspirin) have been linked to Reye's syndrome in children with flu. Diclofenac and mefenamic acid are also linked to enceophalopathy in children with flu (see Miziguchi et al 2007). Hama says some case control studies of fever reducing drugs in flu are urgently needed. I can't help but agree!

The second letter  from Tsunetoshi Shimazu of Shimazu Clinic in Kyoto, Japan notes that aspirin was used by patients in the 1918 flu epidemic to reduce fever. But, he says, a study in 1921 suggests mortality in those who used aspirin was 5-30% and in those who didn't it was 1%. Can we believe this - the author of that study was a homeopath- did he have an unbiased view? Then again what doses did people take? It is suggested that the dosing was higher than we would use today.

Looking at my flu remedy of choice it doesn't contain NSAIDs but paracetamol (acetaminophen). That cheers me but you have to watch your intake of paracetamol - its easy to overdose and get liver damage.

Information about treating mild flu:

WHO

CDC

I am here at the conference, sweltering in a very warm Sofia (temperatures reaching 40 degrees C), to present a paper on knowledge bases in climate change information. No-one can have failed to notice the huge explosion in papers published relating to climate change, from around a couple of hundred in the early 1990s to over 5000 currently (see graph which is based on publications listed in CAB Abstracts).

Keeping up to date with current developments in the face of such a deluge of information is presenting its own set of challenges to scientists working in the field and I was interested to hear how scientists were using a variety of methods to keep track of recently published work such as table of contents alerts from their favourite journals, searches of bibliographic databases and perusing Current Contents.

Not surprisingly, many of the papers being presented are on forest tree species with a particular emphasis on spread and ecological diversification following the last glaciation. Techniques used to assess genetic diversity include the use of molecular markers such as RFLPs, SNPs, microsatellites and AFLPs.  However, some of the work reported deals with other taxa such as beetles, brown bears and even humans (X chromosome diversity in Armenians).

The Balkan peninsula (the area bounded by the Black Sea, Adriatic and the Ionian Seas) has a high biodiversity, in particular genetic diversity. This is due to a number of reasons including a southern location combined with high mountains, the influence of rich biogeographic regions nearby, and also due to the fact that the Balkans were almost unaffected by the last glaciations, making it a site of several glacial refugia. Climate change projections for this region suggest more extremes of temperature and severe droughts in summer which will place pressure on the flora and fauna with increased incidence of forest fires and habitat fragmentation. Several studies presented at the conference examined the changes in biodiversity resulting from palaeoclimatic changes which may give an indication of how populations will fare in the future.

The conference and associated meetings at institutions nearby in Sofia and Plovdiv have been incredibly useful giving me the opportunity to obtain valuable feedback from researchers and librarians on CABI’s information resources such as CAB Abstracts and Environmental Impact. There was a great deal of interest in Environmental Impact with many researchers being impressed by the wide range of content such as the bibliographic database (1.1 million records), reviews, articles, E-books, etc. I have also been collecting a considerable amount of Bulgarian conference proceedings, journals and monographs for inclusion in the CABI Full Text repository. This repository allows us to link full text PDFs to the corresponding bibliographic records in our databases. Researchers have been eagerly contributing material for inclusion in the repository to reach a global audience for the work of Bulgarian scientists active in the fields of forestry and ecology.

For more information on the Full Text project please click the link: http://www.cabi.org/datapage.asp?iDocID=227

For more information on the Environmental Impact internet resource please click the link: http://www.cabi.org/datapage.asp?iDocID=231

As I screened a journal called Elements for the CAB Abstracts database the other day, I came across an interesting article entitled ‘Bentonite, bandaids and borborygmi’ (1), which is all about  the practice of eating clay for gastrointestinal ailments and applying clay topically as a dressing or bandaids for skin infections. Apparently it is a practice as old as mankind and has been observed in cultures worldwide (2). Could the vast surface area and chemical/physical properties of bentonites provide a natural pharmacy of antibacterial agents? Read on to find out!

The deliberate consumption of soil for medicinal or spiritual healing – Geophagy – is a practice that provides a direct connection between human health and Earth’s rocks and minerals. Intermediates in the food chain are eliminated, thus providing direct access to potentially beneficial or harmful elements and compounds associated with the ingested materials. The article by Williams et al. showed that the healing practices of ancient cultures, as well as of modern society, have depended on clay minerals to treat a variety of topical and internal ailments. High cation exchange capacity and extremely fine particle size explain why these minerals are used topically as bandaids to absorb secretions, toxins and contaminants.

Clays are believed to cleanse and refresh the skin and aid in the healing of blemishes; hence, the natural clays with adsorptive and absorptive properties have been exploited in cosmetics and pharmaceuticals. This is based on a simple clay property, i.e. the attractive power of clay-particle surfaces; negatively charged surfaces attract positively charged substances and, like a sponge, clay minerals absorb substances between the layers of their crystal structure. Cation exchange can take up or release toxins or nutrients such as calcium and iron that may be used by bacteria and therefore starve them.

Haydel et al. (3) documented distinct antibacterial properties of iron-rich clays for healing severe skin infections. French green clays, sold as ‘healing clays’ were used to treat a necrotic mycobacterial skin infection called Buruli ulcer. This motivated testing of bentonites from around the world and resulted in the identification of several clays with bactericidal effects on a broad spectrum of human pathogens. The clay penetrates the bacterial cells and either tear them when the clay expands or poisons them. However, Williams et al. 2008 (4) pointed out that while a bactericide that works by physical processes is desirable for applications where contact between a cell and clay is possible, for example air filters, sewage systems, cell lysis (tear) resulting from physical contact with natural or modified clays makes its use on human tissue potentially harmful.

Although the use of clay on the skin as an antibacterial cleanser seems promising and is an acceptable practice, it’s ingestion is not recommended because the consequences for human health can be risky, with the most severe risk of eating clay being a total blockage of the lower intestine, which can only be remedied by surgery (5). Eating clay can also result in nutrient deficiencies. Other complications are detrimental effects on the teeth and gums and the digestive system, nutrient excesses, poisoning, and parasitic invasions. Reports on health effects of Geophagy are conflicting. For example, consumption of some clays causes high levels of potassium in the blood, while others promotes low potassium.

A search on Geophagy in the CAB Abstracts database resulted 97 other abstracts on the subject and not only on the practice by humans but also various animals. I also came across another recent article in Environmental Geochemistry and Health on Geophagy practice by Asian elephants, which found that elephants ate soils mainly not to supplement the mineral contents of their forage but to detoxify unpalatable compounds in their diet.

References

1-     Williams LB, Haydel SE, Ferrell Jr. RE (2009). Bentonite, bandaids, and borborygmi. Elements 5: 99-104.

2-     Ferrell RE, Vermeer DE, LeBlanc WS (1985) Chemical and mineralogical composition of geophagical materials. In: Trace substances in environmental health XIX.  University of Missouri, pp 47-55.

3-     Haydel SE, Remenith CM, Williams LB (2008). Broad-spectrum in vitro antibacterial activities of clay minerals against antibiotic-susceptible and antibiotic-resistant bacterial pathogens. Journal of Antimicrobial Chemotherapy 61: 353-361.

4-     Williams LB, Haydel SE, Glese RF Jr, Eberl DD (2008). Chemical and mineralogical characteristics of French green clays used for healing. Clays and Clay Minerals 56: 437-452.

5-     Padilla FV, de la Torre AM (2006). La pica: retrado de una entidad clinica poco conocida. Nutricion Hospitalaria 21: 557-566.

The meetings bring together over 4,000 participants from 182 countries, including government delegates, representatives from business and industry, environmental organizations and research institutions.

I have been following reports from the meetings and adding relevant extracts to the CABI Environmental Impact news section. 

During the Bonn Climate Change Talks, the IISD Reporting Services, in cooperation with the UNFCCC Secretariat, has been providing:

1)     Daily 3000-word Earth Negotiations Bulletin reports in English and Japanese each day;

2)     Digital photos in thumbnail and high-resolution;

3)     Coverage of selected side events in a separate publication, ENB on the Side

4)     Free email distribution of the Earth Negotiations Bulletin and ENB on the Side

5)     Twitter updates on developments in the negotiations and links to individual coverage of side events.

The main page for the meeting is: http://www.iisd.ca/climate/sb30/, including daily web coverage of negotiations and selected side events.

Follow them on Twitter during climate change meetings (Bonn, Bangkok, Barcelona, Copenhagen and beyond): http://twitter.com/enbclimate