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Mobiles ‘May Cause Brain Cancer’, WHO


The World Health Organization’s cancer research agency says mobile phones are “possibly carcinogenic”.

mobile phones may cause cancer

A review of evidence suggests an increased risk of a malignant type of brain cancer cannot be ruled out.

However, any link is not certain – they concluded that it was “not clearly established that it does cause cancer in humans”.

A cancer charity said the evidence was too weak to draw strong conclusions from.

A group of 31 experts has been meeting in Lyon, France, to review human evidence coming from epidemiological studies.

They said they looked at all relevant human studies of people using mobile phones and exposure to electromagnetic fields in their workplace.

The WHO’s International Agency for Research on Cancer (IARC) can give mobile phones one of five scientific labels: carcinogenic, probably carcinogenic, possibly carcinogenic, not classifiable or not carcinogenic.

It concluded that mobiles should be rated as “possibly carcinogenic” because of a possible link with a type of brain cancer – glioma.

Ed Yong, head of health information at Cancer Research UK, said: “The WHO’s verdict means that there is some evidence linking mobile phones to cancer but it is too weak to draw strong conclusions from.

What else is labelled possibly carcinogenic?

  • Car exhausts
  • Lead
  • Coffee
  • Dry cleaning

“The vast majority of existing studies have not found a link between phones and cancer, and if such a link exists, it is unlikely to be a large one.

“The risk of brain cancer is similar in people who use mobile phones compared to those who don’t, and rates of this cancer have not gone up in recent years despite a dramatic rise in phone use during the 1980s.

“However, not enough is known to totally rule out a risk, and there has been very little research on the long-term effects of using phones.”

The WHO estimated that there are five billion mobile phone subscriptions globally.

Christopher Wild, director of the IARC, said: “Given the potential consequences for public health of this classification and findings it is important that additional research be conducted into the long term, heavy use of mobile phones.

“Pending the availability of such information, it is important to take pragmatic measures to reduce exposure such as hands free devices or texting.”

By James Gallagher Health reporter, BBC News
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UN Calls for Better Grain Storage to Reduce Africa’s Post-harvest Losses

31 May 2011 – Large amounts of food in sub-Saharan Africa goes to waste as a result of inappropriate storage, the United Nations Food and Agriculture Organization (FAO) said in a report unveiled today, which calls for investing in post-harvest technologies to reduce to the losses and boost the continent’s food security.

The joint FAO-World Bank report, entitled Missing Food: The Case of Postharvest Grain Losses in Sub-Saharan Africa, estimates the value of grain losses in sub-Saharan Africa at around $4 billion a year.

“This lost food could meet the minimum annual food requirements of at least 48 million people,” said Maria Helena Semedo, the FAO Assistant Director-General. “If we agree that sustainable agricultural systems need to be developed to feed 9 billion people by 2050, addressing waste across the entire food chain must be a critical pillar of future national food strategies,” she said.

According to estimates provided by the African Postharvest Losses Information System, physical grain losses prior to processing can range from 10 to 20 per cent of African annual production, which is worth $27 billion.

Losses occur when grain decays or is infested by pests, fungi or microbes, and physical losses, but the waste can also be economic, resulting from low prices and lack of access to markets for poor quality or contaminated grain.

According to the report, food losses contribute to high food prices by removing part of the food supply from the market. They also have a negative environmental impact as land, water and resources such as fertilizer and energy are used to produce, process, handle and transport food that no one consumes.

“Reducing food losses is increasingly recognized as part of an integrated approach to realizing agriculture’s full potential, along with making effective use of today’s crops, improving productivity on existing farmland, and sustainably bringing additional acreage into production,” said Jamal Saghir, the Director of the Sustainable Development Department of the World Bank’s Africa Region.

A variety of practices and technologies are available for reducing post-harvest losses, including crop “protectants” and storage containers such as hermetically sealed bags and metallic silos, the report notes.

Those technologies have proved successful in Asia, but more research is needed to identify methods adapted to local environments in Africa. To succeed, interventions must be sensitive to local conditions and practices.

The report recommends that governments create enabling conditions for farmers by reducing market transaction costs through investing in infrastructure such as roads, electricity and water, and strengthening agricultural research and extension services.

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Higher Density Means World Forests Are Capturing More Carbon, News Release

University of Helsinki, Finland and Rockefeller University, USA

Study challenges carbon storage measurements based on forest area;

Several national increases of density and / or area signal “The Great Reversal”

is underway in forests globally after centuries of loss and decline

Forests in many regions are becoming larger carbon sinks thanks to higher density, US and European researchers say in a new report.

In Europe and North America, increased density significantly raised carbon storage despite little or no expansion of forest area, according to the study, led by Aapo Rautiainen of the University of Helsinki, Finland, and published by the online, open-access journal PLoS One.

Even in the South American nations studied, more density helped maintain regional carbon levels in the face of deforestation.

The researchers analyzed information from 68 nations, which together account for 72% of the world’s forested land and 68% of reported carbon mass.  They conclude that managing forests for timber growth and density offers a way to increase stored carbon, even with little or no expansion of forest area.

“In 2004 emissions and removals of carbon dioxide from land use, land-use change and forestry comprised about one fifth of total emissions. Tempering the fifth by slowing or reversing the loss of carbon in forests would be a worthwhile mitigation.

The great role of density means that not only conservation of forest area but also managing denser, healthier forests can mitigate  carbon emission,” says Mr. Rautiainen.

Co-author Paul E. Waggoner, a forestry expert with Connecticut’s Agricultural Experiment Station, says remote sensing by satellites of the world’s forest area brings access to remote places and a uniform method. “However, to speak of carbon, we must look beyond measurements of area and apply forestry methods traditionally used to measure timber volumes.”

Says co-author Iddo Wernick of The Rockefeller University’s Program for the Human Environment: “Forests are like cities – they can grow both by spreading and by becoming denser.”

The authors say most regions and almost all temperate nations have stopped losing forest and the study’s findings constitute a new signal of what co-author Jesse Ausubel of Rockefeller calls “The Great Reversal” underway in global forests after centuries of loss and decline.  “Opportunities to absorb carbon and restore the world’s forests can come through increasing density or area or both.”

To examine how changing forest area and density affect timber volume and carbon, the study team first focused on the United States, where the US Forest Service has conducted a continuing inventory of forest area, timberland area, and growing stock since 1953.

They found that while US timberland area grew only 1% between 1953 and 2007, the combined national volume of growing stock increased by an impressive 51%.  National forest density increased substantially.

For an international perspective, the research team examined the 2010 Global Forest Resources Assessment compiled by the UN Food and Agriculture Organization (FAO), which provides consistent figures for the years 1990-2010.

The data reveal uncorrelated changes of forest area and density. Countries in Africa and South America, which lost about 10% of their forest area over the two decades, lost somewhat less carbon, indicating a small rise in forest density.

In Asia during the second decade of the study period, density rose in 10 of the region’s 21 countries.  Indonesia’s major loss of density and sequestered carbon, however, offset any gain in carbon storage in other Asian nations.

Europe, like the US, demonstrated substantial density gains, adding carbon well in excess of the estimated carbon absorbed by the larger forested area.

Says study co-author Pekka Kauppi, of the University of Helsinki, Finland: “With so much bad news available on World Environment Day, we are pleased to report that, of 68 nations studied, forest area is expanding in 45 and density is also increasing in 45.  Changing area and density combined had a positive impact on the carbon stock in 51 countries.”

Finnish forest - then and now (Photo credit : I.K. Inha & K.A. Ennola
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Study Shows ARVs Can Protect the Uninfected Against HIV

Khopotso Bodibe
AllAfrica

A multi-national study shows that if an HIV-positive person starts taking antiretroviral therapy early on, that is, when their CD 4 count is still high, their chances of infecting their HIV-negative partner can decrease by as much as 96%.

The results of the study are viewed as confirmation of untested wisdom among clinicians who have for a number of years thought that people on combination antiretroviral therapy have a lower chance of transmitting HIV to their uninfected partners. This was presumed on the basis that ARVs fight off HIV infection, which results in the reduction of the viral load in one’s system. The study involved almost 1 800 people in sero-discordant relationships, where one partner has HIV and the other doesn’t. They were from Africa, Asia and the Americas. In South Africa, the study was conducted at two sites in Johannesburg – Helen Joseph and Chris Hani Baragwanath Academic hospitals, and involved almost 100 participants. A key requirement was that they needed to have a considerably higher CD 4 count of 350 – 550.

“We were looking to confirm or to evaluate whether combination antiretroviral treatment can interrupt HIV transmission between HIV-discordant partners”, says Dr Guy de Bruyn, the principal investigator who conducted the clinical study at Chris Hani Bara.

The result showed a significant potential.

“We’ve shown that there’s a 96% reduction in transmission of HIV from the positive partner to the negative partner”, says Dr Sharlaal Badal-Faesen, the principal investigator at the Helen Joseph Hospital site.

This was a randomised study where participants were divided into two groups. Those on the intervention arm were given different ARV combinations and those on the control arm started receiving ARVs only when they reached a stage where, according to national AIDS treatment guidelines, they would qualify for treatment at a CD 4 count of 200 or when they started getting ill with AIDS defining symptoms.

“On the one arm, 50% of these patients received ARVs immediately. On the second arm, those patients did not receive ARVs when they started on the trial. They were monitored until their CD 4 counts reached 250 or below, and then initiated on ARVs. So, in that way we could compare subjects that got ARVs to subjects that do not get ARVs”, explains Dr Badal-Faesen.

Dr de Bruyn adds that “there had been 28 infections that were linked in other words, that were demonstrated by molecular methods to have come from the HIV-infected partner and passed to the initially uninfected partner. Of those 28, 27 were in the group that received treatment according to guidelines and only one was in the group that received immediate antiretroviral therapy. So, that is where we arrived at the 96% difference comparing those two rates”.

He says throughout the study, participants were advised to follow safe sexual practices, which some might have followed adequately and others not. That, then, would explain the differences in levels of infection in both study groups.

“What we are reporting is the actual number of infections that occurred. Essentially, we’re showing that the immediate treatment arm was protected at a far higher rate than people that were in the arm that was treated per guidelines. We assume that the behaviours, on average, would have been similar across both groups. That’s something that’s inherent in a randomised trial. For example, potentially by the act of randomization, the propensity to use condoms when advised to do so should be equally distributed between the two groups”, Dr de Bruyn says.

The second element of the study was to investigate whether early anti-retroviral therapy can protect HIV-positive people from HIV-associated illnesses, as “starting patients earlier on ARVs obviously improves their immunity. So, in so doing they have the added advantage of protection from opportunistic infection”, adds Dr Badal-Faesen.

“In this particular study we’ve shown that there was a 40% reduction in morbidity”, she says.

The recommendations arising out of the findings suggest that early intervention with ARVs could reduce morbidity in HIV-infected people as well as add to HIV prevention methods that exist.

“The implication is that we need to be providing treatment earlier than we do currently. The benefit to the individual receiving treatment is present whether you start late, when it’s life saving, or earlier, in which case you reduce clinical events as we saw in this study. Not only is it beneficial to the individual, but it’s also highly effective in reducing transmission to their partners. And that, hopefully, could be an important tool in reducing the epidemic”, concludes Dr de Bruyn.

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Climate Change and its Implications for Africa

The gradual and deliberate change of the climate occasioned by humans’ quest for a more pleasurable and modern way of life devoid of the sedentary and drudgery that characterized the type of life their ancestors lived has begun to take its toll on all corners of the globe.

Climate change is actually a change in the general atmospheric and weather conditions of a place that may bring about a deleterious effect on the environment. Over the years, particularly beginning from the 19th century , humans’ activities in the environment have been having  a negative  consequence on the climate and environment, such that experts have argued that there is in fact a positive correlation between harmful environmental practices and climate change. Human’s quest for the good life has led to massive deforestation, dredging and silting up of rivers, emission of industrial effluents which cause air pollution, mass manufacture of automobiles with internal combustion engines which emits harmful carbon monoxide amongst several other practices have grossly distorted the natural cycle, such that in many parts of the globe several natural hazards have become a regular occurrence.

In Africa, for instance one imminent threat is the geographical advancement of the Sahara desert leading to desertification in most parts of sub Saharan Africa. The irregularity of the rains in most parts of sub Saharan Africa is also a looming threat which has been linked to climate change. For instance in Northern Nigeria, the possibility that this year is going to be one of drought looks certain as the rains have refused to start  as at march when  it is due, forcing farmers to delay their planting season which will inadvertently affect harvests. This is also likely to be the situation in most parts of Africa, as agriculture is still “rain fed” in most parts of the continent. The intense heating and high rate of evaporation in most parts of the continent also calls for concern as it has resulted in the shrinking some say disappearance of the Lake Chad, a major inland drainage basin with serious consequence for the water cycle.

Unless a concerted effort is made by all stakeholders, on this topical issue of climate change especially in Africa, it is feared that in the not too distant future, the continent may face serious environmental challenges as a result of climate change.

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Why You Should Plan to Deliver in the Fall

Babies born in spring are slightly more likely to develop anorexia nervosa (an eating disorder characterized by extremely low body weight, distorted body image and an obsessive fear of gaining weight), while those born in the fall have a lower risk, say researchers.

A report published in the British Journal of Psychiatry suggests temperature, sunlight, infection or the mother’s diet could be responsible.

Other academics said the effect was small and the disorder had many causes.

The researchers analysed data from four previous studies including 1,293 people with anorexia.

The researchers found an “excess of anorexia nervosa births” between March and June – for every seven anorexia cases expected, there were in fact eight.

There were also fewer than expected cases in September and October.

Dr Lahiru Handunnetthi, one of the report’s authors, at the Wellcome Trust Centre for Human Genetics, said: “A number of previous studies have found that mental illnesses such as schizophrenia, bipolar disorder and major depression are more common among those born in the spring – so this finding in anorexia is perhaps not surprising.

Screening methods

“However, our study only provides evidence of an association. Now we need more research to identify which factors are putting people at particular risk.”

The report suggests seasonal changes in temperature, sunlight exposure and vitamin D levels, maternal nutrition and infections as “strong candidate factors”.

Dr Terence Dovey, from the Centre for Research into Eating Disorders, at Loughborough University, said: “Anorexia is a very complex multifaceted disorder,” adding that the study looked at just one aspect.

“Should we concentrate screening methods to those born in the winter months? No, we should not. It leaves too much error of margin and the potential significant difference is only small.”

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Using Mosquitoes To ‘Vaccinate’ Against Malaria

Joanne Silberner,NPR

The parasite responsible for the intense fevers, chills, and headaches of malaria is very skilled at hiding in the in the body. That means vaccines don’t work all that well to prevent the disease.

So Dutch researchers are trying a new approach — “vaccinating” people by having them get bitten by mosquitoes carrying the malaria parasite, which is similar to how people get infected in the real world. And it seems that this technique may keep people safe from the disease more than two years later.

The Dutch way is different than the conventional vaccine approach of injecting people with bits and pieces of the malaria parasite, or a parasite that’s been weakened in the lab.

Those traditional approaches haven’t been working all that well in clinical trials. The Plasmodium parasite is notoriously tough to manipulate because it spends most of its time hiding inside red blood cells and liver cells, out of sight of the immune system. That’s one reason why it was able to kill 781,000 people in 2009. Most of those were children in developing countries.

In the Dutch experiment, 10 volunteers were bitten multiple times by malarious mosquitoes. The researchers then gave the volunteers an anti-malaria drug, chloroquine. (And yes, the researchers were very careful to pick a malaria type that can be vanquished by chloroquine, not a variety resistant to the drug.)

A couple of years ago, the researchers reported that this process works in the short run to protect against malaria. But that’s not such a big deal. People naturally infected by malaria build up an immunity that holds for several months.

What’s new is that the researchers went back to six of the volunteers 28 months later. Once again the volunteers allowed themselves to be bitten by malarious mosquitoes. Four of the six did not get infected. And the immune systems of the remaining two put up a fight – their infections were delayed (and quickly treated). The results were published online in The Lancet.

Wondering who would volunteer to be bitten by a malarious mosquito? Study author Robert Sauerwein of Radboud University in the Netherlands says most were university students. And the trial was designed pretty carefully.

A lot more work needs to be done to test this approach. This study was very small – only six people. And the researchers note that they may have stacked the deck a little – they used the exact same strain of malaria to infect, and to re-infect. And they worked with adults with mature immune systems, rather than children.

It’s not clear yet why the experimental vaccination protected longer than infection by mosquito in the field. The anti-malarial drug could have helped. Or maybe it was the intense exposure to multiple bites at the same time. Whatever the reason, they say, it’s worth investigating given how well the malaria parasite has been at outsmarting attempts to get rid of it.

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