Indian boffins come up with ‘green’ way of decomposing BPA-containing plastic

May 13, 2010 By Leave a Comment

Washington, May 13 (ANI): Fungi may provide an eco-friendly way of decomposing polycarbonate plastic waste containing bisphenol A ((BPA), two Indian scientists have suggested.

Mukesh Doble and Trishul Artham say manufacturers produce about 2.7 million tons of plastic containing BPA each year.

Polycarbonate is an extremely recalcitrant plastic, used in everything from screwdriver handles to eyeglass lenses, DVDs, and CDs.

Some studies have suggested that the BPA may have a range of adverse health effects, sparking the search for an environmentally safe way of disposing of waste plastic to avoid release of BPA.

The scientists pretreated polycarbonate with ultraviolet light and heat and exposed it to three kinds of fungi — including the fabled white-rot fungus, used commercially for environmental remediation of the toughest pollutants.

They found that fungi grew better on pretreated plastic, using its BPA and other ingredients as a source of energy and breaking down the plastic.

After 12 months, there was almost no decomposition of the untreated plastic, compared to substantial decomposition of the pretreated plastic, with no release of BPA.

The study has appeared in ACS” Biomacromolecules, a monthly journal. (ANI)

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Plant roots ‘can purify dirty water’

May 6, 2010 By Leave a Comment

Washington, May 6 (ANI): A group of horticulturists claim to have discovered that plant roots can, to a limited degree, purify dirty washing machine water.

According to the Penn State horticulturists, plant roots enmeshed in layers of discarded materials inside upright pipes can purify dirty water from a washing machine, making it fit for growing vegetables and flushing toilets.

“Our global fresh water supplies are fast depleting,” said Robert D. Cameron, doctoral student in horticulture. “So it is critical that we begin to look at alternatives on how we can take wastewater and turn it into a resource.”

Cameron and Robert D. Berghage, associate professor of horticulture, use discarded materials and a combination of plant and bacterial communities to treat water from a washing machine and other wastewater.

According to Cameron, this design is superior to previous living treatment systems in that it requires much less space and is much more efficient at removing contaminants.

“We have shown that with this system we can take wastewater from a washing machine and remove more than 90 percent of the pollutants within three days,” said Cameron. “The treated water had very low levels of suspended solids and no detectable levels of e.coli.”

Cameron presented the work at a meeting on organic and sustainable agriculture in Havana. (ANI)

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Chemical exposure before mid-30s ‘ups breast cancer risk’

April 1, 2010 By Leave a Comment

Washington, April 1 (ANI): Women exposed to chemicals and pollutants in the workplace before they reach mid-30s may have a higher risk of developing breast cancer later in life, says a new research.

The study revealed that women exposed to synthetic fibres and petroleum products during the course of their work are most at risk.

The findings are based on more than 1100 women, 556 of whom were diagnosed with breast cancer in 1996/7 in Montreal, Canada, when aged between 50 and 75 and who had gone through the menopause.

The other 613 women, who were matched for age and date of diagnosis, had a range of other cancers, and were intended to act as a comparison group.

An expert team of chemists and industrial hygienists then set about investigating the women”s levels of exposure to around 300 different substances throughout the course of their employment history.

After taking account of the usual factors associated with an increased risk of breast cancer, the analysis indicated a link between occupational exposure to several of these substances.

Compared with the comparison group, this risk peaked for exposures before the age of 36, and was magnified with each additional decade of exposure before this age.

This resulted in women occupationally exposed to acrylic fibres running a seven-fold risk of breast cancer, while those exposed to nylon fibres almost doubled their risk.

The study has been published in Occupational and Environmental Medicine. (ANI)

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Ban of e-waste export likely to worsen global environmental problem

March 22, 2010 By Leave a Comment

Washington, March 22 (ANI): In a new study, researchers have determined that a proposal under debate in the US Congress to ban the export of electronics waste would likely make a growing global environmental problem even worse.

The researchers call into question conventional thinking that trade bans can prevent “backyard recycling” of electronics waste – primarily old and obsolete computers – in developing countries.

Primitive recycling processes used in these countries are dispersing materials and pollutants that are contaminating air, water and soil.

“Trade bans will become increasingly irrelevant in solving the problem,” said Eric Williams.

Electronics waste is often exported from the United States and other developed nations to regions in China, India, Thailand and less developed countries where recycling is done in a crude fashion.

To recover copper from e-waste, for instance, wires are pulled out, piled up and burned to remove insulation covering the copper.

This emits dioxins and other pollutants.

Toxic cyanide and acids used to remove gold from circuit boards of junked computers also are released into the environment.

According to the researchers, with the number of junked computers expected to triple in the next 15 years, the problem will grow much worse if an effective remedy is not put in place in the near future.

The main approach to solving the backyard recycling problem has been to ban trade in e-waste.

Some countries have officially banned e-waste imports, but in some cases, as in China, such legislation has pushed the trade to the black market.

Congress is debating House Resolution 2595, which would ban the export of e-waste from the United States.

“The underlying assumption of this bill and other trade bans is that most e-waste comes from outside developing nations, and that stopping trade with developed countries would cut off the supply of e-waste and stop backyard recycling,” Williams said.

But, authors of the Environmental Science and Technology article forecast that the developing world will generate more waste computers than the developed countries as soon as 2017, and that by 2025, the developing world will generate twice the amount of waste computers as what will come from developed nations.

“Rapid economic and population growth in developing countries is driving an increase in computer use in these parts of the world that is outpacing the implementation of modern and environment-friendly recycling systems,” Williams said.

“So without action, backyard recycling is certain to increase,” he added. (ANI)

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Environmental stresses could be shrinking polar bears

August 26, 2009 By Leave a Comment

London, August 26 (ANI): A new research has indicated that environmental stresses could be causing physical changes in the bears, making them shrink over the last century.

According to a report by BBC News, the conclusion was arrived at by scientists after comparing bear skulls from the early 20th Century with those from the latter half of the century.

Their study describes changes in size and shape that could be linked an increase in pollution and the reduction in sea ice.

Physical “stress” caused by pollutants in the bears’ bodies, and the increased effort needed to find food, could limit the animals’ growth, according to the team.

The researchers used the skulls as indicators of body size. The skulls from the later period were between two and 9 percent smaller.

“Because the ice is melting, the bears have to use much more energy to hunt their prey,” explained Cino Pertoldi, professor of biology from Aarhus University and the Polish Academy of Science, and lead scientist in this study.

“Imagine you have two twins – one is well fed during its growth and one is starving. (The starving) one will be much smaller, because it will not have enough energy to allocate to growth,” he said.

The team, which included colleagues from Aarhus University’s Department of Arctic Environment, also found shape differences between the skulls from the different periods.

“This development was slightly more mysterious,” said Dr Pertoldi.

He explained that it was not possible to determine the cause, but that the changes could be linked to the environment – more specifically to pollutants that have built up in the Arctic, and in the polar bears’ bodies.

The aim of the study was to compare two groups of animals that lived during periods when sea ice extent and pollution levels were very different.

The pollutants that the scientists focused on were compounds containing carbon and halogens – fluorine, chlorine, bromine or iodine.

Some of these compounds have already been phased out, but many still have important uses in industry. These include solvents, pesticides, refrigerants, adhesives and coatings.

The changes, according to the team, could also be related to a reduction in the genetic diversity of the species.

Hunting over the last century, could have depleted the gene pool, leaving polar bears to suffer the effects of inbreeding, according to Dr Pertoldi

“We also know from previous studies that some chlorinated chemical pollutants have affected the fertility of the females,” he said. (ANI)

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Homes contribute to 50 percent more water pollution than previously believed

August 20, 2009 By Leave a Comment

Washington, August 20 (ANI): A new study has determined that homes are an alarming and probably underestimated source of water pollution, and can contribute to 50 percent more water pollution than previously believed.

Scientists Lorence Oki, Darren Haver and colleagues carried out the study.

In the study, the research team explains that runoff results from rainfall and watering of lawns and gardens, which winds up in municipal storm drains.

The runoff washes fertilizers, pesticides and other contaminants into storm drains, and they eventually appear in rivers, lakes and other bodies of water.

“Results from our sampling and monitoring study revealed high detection frequencies of pollutants such as pesticides and pathogen indicators at all sites,” Oki said of their study of eight residential areas in Sacramento and Orange Counties in California.

Preliminary results of the study suggest that current models may underestimate the amount of pollution contributed by homes by up to 50 percent.

That’s because past estimates focused on rain-based runoff during the wet season.

“Use of pesticides, however, increases noticeably during the dry season due to gardening, and our data contains greater resolution than previous studies,” Oki said.

Pollutants detected in outdoor runoff included ant-control pesticide products.

Previous surveys have shown that the majority of pesticides purchased by homeowners are used to control ants.

To encourage pollutant reduction, the researchers initiated community outreach programs centered on improving both irrigation control and pest management. (ANI)

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Spring agricultural fires can accelerate Arctic melting

May 27, 2009 By Leave a Comment

Washington, May 27 (ANI): A research has found that agricultural fires during spring have an adverse impact on the melting Arctic, because the black carbon or soot produced by the fires can lead to accelerated melting of snow and ice.

The two-year international field campaign known as POLARCAT was conducted most intensively during two three-week periods last spring and summer and focused on the transport of pollutants into the Arctic from lower latitudes.

One surprise discovery was that large-scale agricultural burning in Russia, Kazakhstan, China, the US, Canada, and the Ukraine is having a much greater impact than previously thought.

A particular threat is posed by springtime burning – to remove crop residues for new planting or clear brush for grazing – because the black carbon or soot produced by the fires can lead to an increased melting of snow and ice.

Soot, which is produced through incomplete combustion of biomass and fossil fuels, may account for as much as 30 percent of Arctic warming to date, according to recent estimates.

Soot can warm the surrounding air and, when deposited on ice and snow, absorb solar energy and add to the melting process.

In addition to soot, other short-lived pollutants include ozone and methane.

Although global warming is largely the result of excess accumulation of carbon dioxide (CO2), the Arctic is highly sensitive to short-lived pollutants.

During the UNH workshop, a report by the Clean Air Task Force detailing some of the campaign’s findings on agricultural burning and transport to the Arctic will be officially released.

“Targeting these emissions offers a supplemental and parallel strategy to carbon dioxide reductions, with the advantage of a much faster temperature response, and the benefit of health risk reductions,” said Ellen Baum, senior scientist of the Clean Air Task Force.

“In addition, we have the know-how to control these pollutants today,” she added.

The report notes that during April, at the beginning portion of the field campaign in Northern Alaska, aircraft-based researchers were surprised to find 50 smoke plumes originating from fires in Eurasia more than 3,000 miles away.

Analysis of the plumes, combined with satellite images, revealed the smoke came from agricultural fires in Northern Kazakhstan-Southern Russia and from forest fires in Southern Siberia.

The emissions from fires far outweighed those from fossil fuels, the report states.

“These fires weren’t part of our standard predictions, they weren’t in our models,” said Daniel Jacob, a professor of atmospheric chemistry and environmental engineering at Harvard University. (ANI)

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Yamuna Satyagraha activists protest against metro rail expansion in Delhi

May 11, 2009 By Leave a Comment

New Delhi, May 11 (ANI): The activists of Yamuna Satyagraha here on Sunday protested against the expansion of the Delhi metro rail line touching the banks of river.

The activists observed the opening day of the Yamuna Bank station as “Black Day” in protest against “DMRC’s continues encroachment on the Yamuna’s floodplain in the form of the Yamuna metro complex”.

“We are protested against the encroachment of Yamuna’s floodplains by the Delhi Metro Rail,” said Manoj Mishra, activist, ‘Yamuna Satyagraha’.

Complaining that the new Yamuna Bank depot is located within 300 metres of the river in violation of Delhi High Court orders, the Yamuna activists have written a letter to the to Managing Director of Delhi Metro Rail Construction, E. Sreedharan that while on the one hand all slum clusters were removed from the riverbed in keeping with this order, the DMRC now has been allowed to construct on the floodplains.

On the other hand after inaugurating the Yamuna Bank station, E. Shreedharan said there is no chance of degradation of the Yamuna floodplains because of this new metro rail line.

“We are not letting out any pollutant water or pollutants into the river from this side. But then just imagine what tremendous convenience it would be to the people because we have to definitely come over here to go to Noida and Vaishali areas. There is no other way. So we had to occupy this place but we have ensured that there is no degradation at all,” he added.

The opening of this new extension is likely to reduce the road traffic from the two main bridges namely Nizamuddin Bridge and ITO Bridge connecting East Delhi with the rest of the city as both the bridges are major bottleneck points in terms of traffic. (ANI)

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‘Artificial noses’ come closer to reality

April 24, 2009 By Leave a Comment

Washington, Apr 24 (ANI): By using nanotechnology- or more specifically “nano-electromechanical systems”, or NEMS-scientists have taken a major step towards creating ‘artificial noses’.

In a bid to track down single molecules, nano researchers have developed NEMS, which are actually minute strings that resonate in characteristic fashion.

If a molecule docks onto one of the strings, then it becomes heavier, and its oscillations become measurably slower. But until recently, such methods have not been utilised in many practical applications.

However, physicists at LMU Munich have now made a breakthrough in this field-they have constructed a system of nanostrings made of non-conducting material, where each string can be electrically excited separately.

In this way, thousands of these strings can be produced on a small chip.

“By measuring the period of oscillation, we could therefore detect chemical substances with molecular precision. Ideally, you would have several thousand strings sitting on a chip the size of a fingernail, each one for highly specifically recognizing a single molecule – so you could build an extremely sensitive ‘artificial nose’, for example,” explained Quirin Unterreithmeier, first author of the study.

And one of the devices that could be created with this system is a highly sensitive “artificial nose” that detects various molecules – pollutants for example – individually.

However, until recently, getting such systems to work has proven technically difficult-one problem being to produce and measure the oscillations.

While the nanostrings can be made to oscillate by magnetomechanical, piezoelectric or electrothermal excitement, this only works if the nanostrings are made of metal, or are at least metal-coated, which in turn greatly dampens the oscillations, preventing sensitive measurement.

Not only does it allow the detection of a single molecule, it also makes it harder to distinguish the different signals from differently oscillating strings.

The newly developed method now avoids these difficulties.

The researchers have constructed an NEMS in which the nanostrings are excited individually by dielectric interaction – the same phenomenon that makes hair stand on end in winter.

Using this physical principle, the nanostrings, which are made of electrically non-conducting silicon nitride, are excited to resonate when exposed to an oscillating inhomogeneous electric field, and their vibration then measured.

The alternating electric field required for this stimulation was produced between two gold electrodes right up close to the string and two other electrodes measured the oscillations.

“We created this setup using etching techniques. But this was easily done – even repeated ten thousand times on a chip. The only thing to do now is to make sure the strings can be individually addressed by a suitable circuit,” said a co-author of the study.

Overall, the methods could turn out to be a technically easy exercise – but one that will allow a breakthrough in chemical analysis. (ANI)

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Governments agree to restrict tourism to protect Antarctic

April 20, 2009 By Leave a Comment

Washington – World governments agreed Friday to limit tourism to the Antarctic in an effort to protect the region’s fragile ecosystem, which participants warned has been feeling the effects of climate change more than any other part of the globe.

The 28 members of the Antarctic Treaty Consultative Meeting unanimously agreed to restrict to 100 the number of tourists that could be on the Antarctic’s shores at any one time, as well as limiting cruise ships travelling to the region to 500 passengers each.

The measures, which still have to be ratified by the members, had been pushed by the United States, which hosted the nearly-two week summit in Baltimore. Secretary of State Hillary Rodham Clinton, who opened the summit last week, had warned that protecting the region was crucial to stabilizing the global climate.

Gerald Leape of the Pew Environment Group, a US-based climate group, welcomed the new restrictions but said they did not go far enough to limit tourism. He pushed for an annual cap on the number of people that visit the poles, rather than just limits on ship passengers.

“Visiting Antarctica should be a privilege. It’s not a right,” Leape said in an interview.

The summit also agreed to new safety rules for ships travelling to the poles and reviewed the latest science on climate change’s impact. Two US studies released ahead of the conference suggested polar ice was melting faster than expected as global temperatures rise.

Tucker Scully, who chaired the conference, said monitoring the poles was providing an “understanding of the changes that are taking place in the global climate.”

The gathering marked the first US-hosted summit on the environment since President Barack Obama took office in January, and comes as world governments are hoping to reach a new deal by December to curb the pollutants that cause global warming. (dpa)

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Using cellulosic ethanol in vehicles may benefit human health and environment

February 3, 2009 By Leave a Comment

Washington, Feb 3 (ANI): A new research has determined that using cellulosic ethanol as the fuel that drives our vehicles, may be much better for human health and the environment than previously recognized.

The research, by scientists from the University of Minnesota, found that cellulosic ethanol has fewer negative effects on human health because it emits smaller amounts of fine particulate matter, an especially harmful component of air pollution.

Earlier work showed that cellulosic ethanol and other next-generation biofuels also emit lower levels of greenhouse gas emissions.

“Our work highlights the need to expand the biofuels debate beyond its current focus on climate change to include a wider range of effects such as their impacts on air quality,” said lead author Jason Hill, a resident fellow in the University of Minnesota’s Institute on the Environment.

The study is the first to estimate the economic costs to human health and well-being from gasoline, corn-based ethanol and cellulosic ethanol made from biomass.

The researchers found that depending on the materials and technology used in production, cellulosic ethanol’s environmental and health costs are less than half the costs of gasoline, while corn-based ethanol’s costs range from roughly equal to about double that of gasoline.

Total environmental and health costs of gasoline are about 71 cents per gallon, while an equivalent amount of corn-ethanol fuel costs from 72 cents to about 1.45 dollars, depending on the technology used to produce it.

An equivalent amount of cellulosic ethanol, however, costs from 19 cents to 32 cents, depending on the technology and type of cellulosic materials used.

The researchers looked at pollutants emitted at all stages of the life cycles of the three types of fuel, including when they are produced and used.

They considered three methods of producing corn-based ethanol and four methods of producing cellulosic ethanol.

“To understand the environmental and health consequences of biofuels, we must look well beyond the tailpipe to how and where biofuels are produced. Clearly, upstream emissions matter,” Hill said.

The research also points out that other potential advantages of cellulosic biofuels, such as reducing the amount of fertilizer and pesticide runoff into rivers and lakes, may also add to the economic benefit of transitioning to next-generation biofuels. (ANI)

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Using cellulosic ethanol in vehicles may benefit human health and environment

February 3, 2009 By Leave a Comment

Washington, Feb 3 (ANI): A new research has determined that using cellulosic ethanol as the fuel that drives our vehicles, may be much better for human health and the environment than previously recognized.

The research, by scientists from the University of Minnesota, found that cellulosic ethanol has fewer negative effects on human health because it emits smaller amounts of fine particulate matter, an especially harmful component of air pollution.

Earlier work showed that cellulosic ethanol and other next-generation biofuels also emit lower levels of greenhouse gas emissions.

“Our work highlights the need to expand the biofuels debate beyond its current focus on climate change to include a wider range of effects such as their impacts on air quality,” said lead author Jason Hill, a resident fellow in the University of Minnesota’s Institute on the Environment.

The study is the first to estimate the economic costs to human health and well-being from gasoline, corn-based ethanol and cellulosic ethanol made from biomass.

The researchers found that depending on the materials and technology used in production, cellulosic ethanol’s environmental and health costs are less than half the costs of gasoline, while corn-based ethanol’s costs range from roughly equal to about double that of gasoline.

Total environmental and health costs of gasoline are about 71 cents per gallon, while an equivalent amount of corn-ethanol fuel costs from 72 cents to about 1.45 dollars, depending on the technology used to produce it.

An equivalent amount of cellulosic ethanol, however, costs from 19 cents to 32 cents, depending on the technology and type of cellulosic materials used.

The researchers looked at pollutants emitted at all stages of the life cycles of the three types of fuel, including when they are produced and used.

They considered three methods of producing corn-based ethanol and four methods of producing cellulosic ethanol.

“To understand the environmental and health consequences of biofuels, we must look well beyond the tailpipe to how and where biofuels are produced. Clearly, upstream emissions matter,” Hill said.

The research also points out that other potential advantages of cellulosic biofuels, such as reducing the amount of fertilizer and pesticide runoff into rivers and lakes, may also add to the economic benefit of transitioning to next-generation biofuels. (ANI)

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Water pollution linked to male fertility problems

January 19, 2009 By Leave a Comment

Washington, January 19 (ANI): A collaborative study has lent more force to the suggestion that water pollution is triggering male fertility problems.

The study involving researchers from Brunel University, the Universities of Exeter and Reading and the Centre for Ecology and Hydrology has revealed that a group of testosterone-blocking chemicals is finding its way into UK rivers, affecting wildlife and potentially humans.

Supported by the Natural Environment Research Council, the study has led to the identification of a new group of chemicals that act as ‘anti-androgens’, which means that they inhibit the function of the male hormone, testosterone, reducing male fertility.

Some of them, according to a research article published in the journal Environmental Health Perspectives, are contained in medicines, including cancer treatments, pharmaceutical treatments, and pesticides used in agriculture.

The researchers think that when these chemicals get into the water system, they may play a pivotal role in causing feminising effects in male fish.

Previous studies conducted by Brunel University and the University of Exeter scientists have already confirmed that female sex hormones (estrogens), and chemicals that mimic estrogens, are leading to ‘feminisation’ of male fish.

These chemicals are found in some industrial chemicals and the contraceptive pill, and enter rivers via sewage treatment works.

The researchers say that this causes reproductive problems by reducing fish breeding capability, and, in some cases, can lead to male fish changing sex.

A link between this phenomenon and the increase in human male fertility problems caused by testicular dysgenesis syndrome has also been suggested by several other studies.

However, scientists could not fully believe in the existence of any such link because the list of suspects causing effects in fish was limited to estrogenic chemicals, whilst testicular dysgenesis is known to be caused by exposure to a range of anti-androgens.

Lead author on the research paper, Dr Susan Jobling at Brunel University’s Institute for the Environment, said: “We have been working intensively in this field for over ten years.

The new research findings illustrate the complexities in unravelling chemical causation of adverse health effects in wildlife populations and re-open the possibility of a human – wildlife connection in which effects seen in wild fish and in humans are caused by similar combinations of chemicals.

We have identified a new group of chemicals in our study on fish, but do not know where they are coming from. A principal aim of our work is now to identify the source of these pollutants and work with regulators and relevant industry to test the effects of a mixture of these chemicals and the already known environmental estrogens and help protect environmental health.”

Senior author Professor Charles Tyler of the University of Exeter said: “Our research shows that a much wider range of chemicals than we previously thought is leading to hormone disruption in fish. This means that the pollutants causing these problems are likely to be coming from a wide variety of sources.

Our findings also strengthen the argument for the cocktail of chemicals in our water leading to hormone disruption in fish, and contributing to the rise in male reproductive problems. There are likely to be many reasons behind the rise in male fertility problems in humans, but these findings could reveal one, previously unknown, factor.”

The researchers are currently focusing on identifying the source of anti-androgenic chemicals, as well as continuing to study their impact on reproductive health in wildlife and humans.(ANI)

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