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Floods and coastal erosion may expose contents of UK landfills, study finds

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The contents of historic coastal landfill sites could pose a significant environmental threat if they erode, according to a new study from Queen Mary University of London (QMUL).

There are 1264 historic coastal landfill sites in England and Wales, all of which are sealed and no longer receive waste, but fall wholly or partially within the Environment Agency’s Tidal Flood Zone 3.

In the first academic study of its kind, researchers from QMUL investigated the contents of two sites in Essex: Leigh Marshes Landfill, used from 1955 to 1967; and Hadleigh Marsh Landfill, used from 1980 to 1987, to determine the potential consequences should the sites be tidally flooded or erode.

The analysis found that 100 per cent of the Leigh Marsh waste samples and 63 per cent of the Hadleigh Marsh samples contained contaminants at concentrations that exceed marine sediment quality guidelines ‘probable effects levels’, indicating that adverse effects to flora and fauna could be expected if the waste was to erode into surrounding coastal wetlands.

The findings are from a forthcoming report for the Environment Agency, authored by Dr Kate Spencer, Reader in Environmental Geochemistry at QMUL, and James Brand, PhD student at QMUL’s School of Geography.

“It’s important to state clearly that we’re not saying these sites are currently eroding. What our findings show is that in the event of erosion, there would be serious environmental consequences due to the level of contaminants that would pollute the surrounding protected ecological sites.”

The main risks to these landfills come from the effects of climate change, including erosion and flooding with salt water from storm surges and higher water levels.

According to Dr Spencer, many of these sites may be vulnerable to erosion and coastal flooding in the future.

“If you take a look inside these sites, they reflect consumption and waste patterns of the time. So one historic landfill site might contain a huge amount of plastics, and another might be full of coal ash. Many of them were in use when there were no rules about what went in. This is important because it means that we can’t draw national conclusions from individual sites — every landfill is essentially unique and some will prove more risky than others.”

Mr Brand said that it was “important to understand the sheer scale of some of these sites”. The Hadleigh Marsh site contains 500,000m3 of waste — if this waste were to erode and be released to the adjacent marsh, there is sufficient material to cover 138 Wembley size football pitches to a depth of half a metre.

The study says that while a policy of relocating the waste away from vulnerable sites would be preferable, it is likely that the waste will continue to be protected in situ due to the enormous costs and risks associated with relocating the waste.

The next stage of the research will create a vulnerability index for historic coastal landfill sites, to determine where resources and attention might best be focused.

source: Queen Mary University of London

Source: Floods and coastal erosion may expose contents of UK landfills, study finds | Science Codex

One in six children hospitalized for lung inflammation positive for marijuana exposure 

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BALTIMORE, MD – A new study to be presented at the Pediatric Academic Societies 2016 Meeting found that one in six infants and toddlers admitted to a Colorado hospital with coughing, wheezing and other symptoms of bronchiolitis tested positive for marijuana exposure.

The study, “Marijuana Exposure in Children Hospitalized for Bronchiolitis,” recruited parents of previously healthy children between one month of age and two years old who were admitted to Children’s Hospital Colorado (CHC) between January 2013 and April 2014 with bronchiolitis, an inflammation of the smallest air passages in the lung. The parents completed a questionnaire about their child’s health, demographics, exposure to tobacco smoke, and as of October 2014, whether anyone in the home used marijuana. Marijuana became legal in Colorado on January 1, 2014.

Of the children who were identified as having been exposed to marijuana smokers, urine samples showed traces of a metabolite of tetrahydrocannabinol (THC), the psychoactive component of marijuana, in 16 percent of them. The results also showed that more of the children were THC positive after legalization (21 percent, compared with 10 percent before), and non-white children were more likely to be exposed than white children.

The findings suggest that secondhand marijuana smoke, which contains carcinogenic and psychoactive chemicals, may be a rising child health concern as marijuana increasingly becomes legal for medical and recreational use in the United States, said lead researcher Karen M. Wilson, MD, MPH, FAAP, an associate professor of pediatrics at the University of Colorado School of Medicine and section head at CHC. Most states with legal marijuana do not restrict its combustion around children, she said.

“Our study demonstrates that, as with secondhand tobacco smoke, children can be exposed to the chemicals in marijuana when it is smoked by someone nearby,” Dr. Wilson said. “Especially as marijuana becomes more available and acceptable, we need to learn more about how this may affect children’s health and development.” In the meantime, she said, “marijuana should never be smoked in the presence of children.”

Source: American Academy of Pediatrics

Source: One in six children hospitalized for lung inflammation positive for marijuana exposure | Science Codex

Scientists uncover history of ancient viruses as far back as 30 million years ago

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Researchers from Boston College, US, have revealed the global spread of an ancient group of retroviruses that affected about 28 of 50 modern mammals’ ancestors some 15 to 30 million years ago.

Retroviruses are abundant in nature and include human immunodeficiency viruses (HIV-1 and -2) and human T-cell leukemia viruses. The scientists’ findings on a specific group of these viruses called ERV-Fc, to be published in the journal eLife, show that they affected a wide range of hosts, including species as diverse as carnivores, rodents, and primates.

The distribution of ERV-Fc among these ancient mammals suggests the viruses spread to every continent except Antarctica and Australia, and that they jumped from one species to another more than 20 times.

The study also places the origins of ERV-Fc at least as far back as the beginning of the Oligocene epoch, a period of dramatic global change marked partly by climatic cooling that led to the Ice Ages. Vast expanses of grasslands emerged around this time, along with large mammals as the world’s predominate fauna.

“Viruses have been with us for billions of years, and exist everywhere that life is found. They therefore have a significant impact on the ecology and evolution of all organisms, from bacteria to humans,” says co-author Welkin Johnson, Professor of Biology at Boston College where his team carried out the research.

“Unfortunately, viruses do not leave fossils behind, meaning we know very little about how they originate and evolve. Over the course of millions of years, however, viral genetic sequences accumulate in the DNA genomes of living organisms, including humans, and can serve as molecular ‘fossils’ for exploring the natural history of viruses and their hosts.”

Using such “fossil” remnants, the team sought to uncover the natural history of ERV-Fc. They were especially curious to know where and when these pathogens were found in the ancient world, which species they infected, and how they adapted to their mammalian hosts.

To do this, they first performed an exhaustive search of mammalian genome sequence databases for ERV-Fc loci and then compared the recovered sequences. For each genome with sufficient ERV-Fc sequence, they reconstructed the sequences of proteins representing the virus that colonized the ancestors of that particular species. These sequences were then used to infer the natural history and evolutionary relationships of ERV-Fc-related viruses.

The studies also allowed the team to pinpoint patterns of evolutionary change in the genes of these viruses, reflecting their adaptation to different kinds of mammalian hosts.

Perhaps most interestingly, the researchers found that these viruses often exchanged genes with each other and with other viruses, suggesting that genetic recombination played a significant role in their evolutionary success.

“Mammalian genomes contain hundreds of thousands of ancient viral fossils similar to ERV-Fc,” says lead author William E. Diehl from the University of Massachusetts, who conducted the study while a post-doctoral researcher at Boston College.

“The challenge will now be to use ancient viral sequences for looking back in time, which may prove insightful for predicting the long-term consequences of newly emerging viral infections. For example, we could potentially assess the impact of HIV on human health 30 million years from now. The method will allow us to better understand when and why new viruses emerge and how long-term contact with them impacts the evolution of host organisms.”

Source: eLife

Source: Scientists uncover history of ancient viruses as far back as 30 million years ago | Science Codex

Sea level rise threatens larger number of people than earlier estimated

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Rising sea level threatens larger number of people that earlier estimated. Shanghai with over 24 million inhabitants is one of the megacities that will suffer from the projected sea level rise and intensified storms. Credit: Olli Varis / Aalto University

More people live close to sea coast than earlier estimated, assess researchers in a new study. These people are the most vulnerable to the rise of the sea level as well as to the increased number of floods and intensified storms. By using recent increased resolution datasets, Aalto University researchers estimate that 1.9 billion inhabitants, or 28% of the world’s total population, live closer than 100 km from the coast in areas less than 100 meters above the present sea level.

By 2050 the amount of people in that zone is predicted to increase to 2.4 billion, while population living lower than 5 meters will reach 500 million people. Many of these people need to adapt their livelihoods to changing climate, say Assistant Professor Matti Kummu from Aalto University.

The study found that while population and wealth concentrate by the sea, food must be grown further and further away from where people live. Highlands and mountain areas are increasingly important from food production point of view, but also very vulnerable to changes in climate.

 

  • Over the past century there has been a clear tendency that cropland and pasture areas have grown most in areas outside the population hotspots, and decreased in coastal areas. This will most probably only continue in the future, summarises Professor Olli Varis from Aalto University.

 

Even though people and wealth continue to accumulate in coastal proximity, their growth is even faster in inland and mountainous areas, the study reveals. This contradicts the existing studies. In the future, the world will be less diverse in terms of urbanisation and economic output, when assessing it from geospatial point of view.

For the analysis, researchers used several global gridded datasets. They first created a geographic zoning in relation to the elevation and proximity to coast. This was then used to study the factors included in the study, which were grouped into five clusters: climate, population, agriculture, economy, and impact on environment. For the factors with temporal extent, the researchers also assessed their development over time period of 1900-2050.

source: Aalto University

Source: Sea level rise threatens larger number of people than earlier estimated | Science Codex

New discoveries on the connection between nicotine and type 2 diabetes

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Researchers at Lund University in Sweden have made two new discoveries with regard to the beta cells’ ability to release insulin. The findings can also provide a possible explanation as to why smokers have an increased risk of type 2 diabetes.

The study was conducted on mice and donated beta cells from humans, and is now published in the scientific journal Cell Reports.

The researchers have discovered that so-called nicotinic acetylcholine (nicotine-sensitive) receptors influence the normal release of insulin. They also show that a specific genetic alteration renders dysfunctional nicotine-receptors affecting the number of functional nicotine-sensitive receptors found in beta cells. A reduced number of functional receptors leads to a decrease in insulin secretion, thereby increasing the risk of developing type 2 diabetes.

“The receptors in the beta cells that stimulate the release of insulin are normally activated by the signal substance acetylcholine, but they can also be activated by nicotine. Never before has the importance of nicotine-sensitive receptors been shown in terms of the function of beta cells. Our research indicates that people who lack these receptors are at higher risk of developing type 2 diabetes”, says Isabella Artner, researcher at Lund University responsible for the study.

Isabella Artner and her colleagues have also discovered that the gene MafA (muscoloaponeurotic fibrosacoma oncogene family A) found in insulin-producing beta cells control the number of nicotine-sensitive receptors and thereby their ability to receive signals from the central nervous system.

“The effect that this single gene, MafA, alone has on insulin secretion was previously unknown, and nicotine receptors have never before been connected to type 2 diabetes”, says Isabella Artner, and continues:

“We know that smokers have an increased risk of developing type 2 diabetes, but the reason why has not been firmly established. Perhaps it has to do with the nicotine-sensitive receptors we describe. Our findings increase knowledge about the connection between smoking and type 2 diabetes.

Source: Lund University

Source: New discoveries on the connection between nicotine and type 2 diabetes | Science Codex