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  • Greening Hydroelectric Power

    Although hydroelectric dams may have several environmental disadvantages, we cannot rule out the fact that these dams will continue to be significant sources of renewable energy for our planet. The best way forward – considering that dam removal is costly, and not always an option – is to propose methods for improvement. But how?

    Reassessing Dams

    One proposed solution by conservation groups, such as American Rivers, is that existing dams should be revisited in order to examine them to come up with possible ways to maximize their efficiency, while at the same time ensuring responsible operation, and environmental friendly performance. They suggest that dams that were built some years ago should be re-examined to determine whether they are still efficient at generating power. Dams that are no longer serving their purpose should be removed rather than left to impair the environment. Alternatively, they should be upgraded with modern technology to improve their efficiency. Money should be channelled into making existing dams more efficient at providing power, rather than being spent on the construction of new dams.

    Dam Removal

    Environmental Engineering

    With proper planning, some of the negative environmental effects caused by hydroelectric plants can be mitigated. By designing and constructing the plant in such a way that water, and the nutrients that it carries, is allowed to continue its journey downstream – allowing fish and other aquatic organisms to move freely past the barrier created – would go a long way to retain the ecological functioning of the river system. Responsible dam management is also key. By mimicking natural patterns of the river in terms of seasonal flow rates, dam managers can effectively retain an ecologically sound ecosystem. If water does not need to be retained in reservoirs for drinking purposes, this can be achieved by constructing diversion hydroelectric plants, rather than reservoirs. A diversion hydroelectric plant obtains water from the river via a channel, to generate power without restricting the downstream flow of water.

    Dam Busters

    To date over 1000 dams have been removed across the United States due to sediment build-up, safety and/or environmental concerns, or due to them being inefficient or having outlived their usefulness to society. A paper that was recently published in Science shows that river systems are resilient and once a dam is removed, they recover relatively quickly.

    "The apparent success of dam removal as a means of river restoration is reflected in the increasing number of dams coming down, more than 1,000 in the last 40 years," said Jim O'Connor, a geologist with the U.S. Geological Survey, and lead author of the paper. "Rivers quickly erode sediment accumulated in former reservoirs and redistribute it downstream, commonly returning the river to conditions similar to those prior to impoundment."

    Studies have shown that river channels typically stabilize within a few months or years rather than decades, especially if dam removal occurs quickly.

    "In many cases, fish and other biological aspects of river ecosystems also respond quickly to dam removal," said co-author of the study Jeff Duda, an ecologist with USGS. "When given the chance, salmon and other migratory fish will move upstream and utilize newly opened habitat."
    The rising number of national and international dam removals has spurred efforts to better understand the consequences in order to help guide future dam removals.

    "As existing dams age and outlive usefulness, dam removal is becoming more common, particularly where it can benefit riverine ecosystems," said Gordon Grant, Forest Service hydrologist. "But it can be a complicated decision with significant economic and ecologic consequences. Better understanding of outcomes enables better decisions about which dams might be good candidates for removal and what the river might look like as a result."

    Considering that hydroelectric dams provide a greener alternative to meeting our planet’s energy requirements, upholding environmental safeguards should not be overlooked. In order to provide a truly green alternative energy resource, hydroelectric plants should not sacrifice the integrity of the environment while doing so. To achieve this, proper planning, careful attention to design, and responsible dam management, is crucial. Greening green power will benefit our earth without harming it at the same time.

    Journal Reference:

    J. E. O'Connor, J. J. Duda, and G. E. Grant. 1000 dams down and counting. Science, April 2015 DOI: 10.1126/science.aaa9204

  • How Green is Hydroelectric Power?

    Dams are man-made structures built across rivers usually to control the flow, regulate flooding and improve navigation. But due to the effects of climate change, dams are now being built at a greater pace to produce hydroelectric power – toted as an affordable, and greener natural source of renewable energy that produces minimal emissions of greenhouse gases. Researchers have been searching for environmentally friendly alternative sources of energy to meet the world’s growing energy demands, and hydroelectric dams seem to be a viable option. Let’s take a look at how environmentally friendly these dams really are.

    Environmental Effects of Dams

    Dams disrupt the natural ecology of rivers. Plants and animal communities that inhabit the river adapt to the river’s patterns of flood and drought, and once that pattern is disturbed, it interrupts the natural cycles of aquatic species. As dams restrict the flow of water downstream, aquatic animals that coordinate their reproduction with the annual flood seasons may be largely affected. Furthermore, a dry river bed can be turned into a raging torrent in a matter of seconds; this not only causes erosion of the riverbank, but rapid fluctuations in temperature and water levels can kill fish, and other aquatic organisms, and even animals and birds that nest in the riparian zone.


    Downstream river inhabitants depend on the river feeding a constant supply of debris, including leaves, branches, twigs and the organic remains of dead animals. Not only is this organic debris an important source of food and nutrients to downstream plant and animal communities, it also provides microhabitats for a range of species – offering shelter and refuge from predators, and providing a substrate for microorganisms and algae to grow. Dams hold back debris, and consequently reduce the flow of both nutrients and habitat for downstream organisms.

    Dams also prevent fish migration. Salmon, for example, require a specific habitat to breed, and migrate upstream to reproduce. The barrier imposed by the dam prevents them from being able to do so, causing these populations to decline. While fish ladders may assist fish to move upstream, not many make their way back downstream through the hydroelectric turbines alive. This may negatively affect the food supply of local residents – both human and animals – that depend on these fish for their survival. It can also affect the livelihood of local people and businesses due to the loss of income opportunities from farming, fishing, tourism, and recreation.

    A Solution to Climate Change – or NOT?

    Researchers have concluded that large dams actually contribute a substantial amount of carbon dioxide and methane – gases responsible for climate change – to the atmosphere. As more dams and reservoirs are constructed, trees that are actually available to absorb carbon dioxide are swamped by water, where they eventually rot at the bottom of the dam. Furthermore, organic debris that is carried downstream accumulates behind the dam wall, and eventually sinks to the floor where it decomposes. This results in Methane gas (also known as swamp gas) that is formed when organic matter decomposes in the absence of oxygen.  The deep, dark, muddy sediments at the bottom of a dam provide an anaerobic environment that is conducive to the production of methane, which is released through the air/water surface interface, and when water flows over dam walls, or gushes through turbines. Methane gas is 25 times more potent than carbon dioxide in terms of its greenhouse effect. Methane emitted from dams accounts for 23% of total anthropogenic methane gas emissions – rather a substantial contribution.

    So, while dams provide healthy alternative to burning fossil fuels, there are some substantial environmental impacts to consider, most importantly the impact to the natural aquatic life and surrounding life that relies on these rivers.

  • Uncovering Chemicals in Fracking Fluids Allows Testing for Water Contamination

    Two new scientific studies have uncovered the organic chemicals found in fracking fluids. These will serve as a basis for testing water across the country for signs of contamination in aquifers, wells, lakes, rivers, and streams. It will also be a starting point for establishing future regulation of the industry if these direct impacts are now shown. The findings, which were published recently in the scientific journals Trends in Environmental Analytical Chemistry and Science of the Total Environment, reveal that fracking fluids contain organic compounds such as biocides, which can be potentially dangerous should they leach into groundwater.

    Drinking Fracking Fluid

    While public awareness about the hazards of water contamination from fracking fluids has grown, the science supporting regulation has been lacking. According to the researchers, it is now time for science to catch up. By focusing research on water contamination from fracking fluids, it is likely that more attention will be cast on this in future, and as a result, improved regulatory measures will follow.

    Fracking is the process used to extract natural gas and oil from shale deposits buried deep underground. Fracking fluid consisting of huge volumes of water laced with added chemicals is injected into wells under high pressure to forces fissures in rocks apart. Once the pressure is released, natural gas is recovered from the well.

    The fracking fluids return to the soil surface as wastewater, which can contaminate both surface water and groundwater resources if not disposed of appropriately. Oil and gas operators add chemical compounds, such as pesticides that prevent bacterial or algal growth, but are very secretive about the ingredients added to these fluids. Consequently, until now, the organic content of fracking fluids remained unknown. The new research studies shed light on the organic components of fracking fluids and provide a method of detecting evidence of water contamination, together with suggested safe water recycling methods to prevent water contamination.

    "A few years ago we started thinking that this could be a significant environmental water problem," explained lead author, Dr. Imma Ferrer, from the University of Colorado, Boulder, USA. "In some cases, the fluid has leaked from pipes and into groundwater. Before we can assess the environmental impact of the fluid, we have to know what to look for. If we find out what's in it, we can check if the groundwater is contaminated."

    Past studies have assessed the inorganic content, such as naturally occurring radioactive elements and salts stemming from rocks and soils. These new studies focus on the organic compounds that operators add to fracking fluid.

    Using a combination of mass spectrometry and liquid chromatography to identify organic compounds in the fluids, the scientists found about a quarter of the organic compounds they believe are present in fracking fluids, including biocides that are potentially hazardous compounds used to kill bacteria that may be present in the fracking fluid and/or well casing. Although they haven't found all the organic compounds they were looking for, the researchers feel that they have found the most important ones necessary to be able to test drinking water and groundwater resources for signs of contamination.

    "It's really exciting because I realized there had been a lot of research done on inorganic compounds, but the organic ones had been left a little bit aside," said Ferrer. "We now have sophisticated analytical techniques we can use to investigate this relatively new area, and this is really our chance to use these tools to identify as many compounds as we can."

    Hopefully this research will help prevent contamination of our water resources and help introduce new regulations to help protect our precious water resources from contamination in future.

    Journal Reference

    "Chemical constituents and analytical approaches for hydraulic fracturing waters" by Imma Ferrer and E. Michael Thurman (doi: 10.1016/j.teac.2015.01.003). The article appears in Trends in Environmental Analytical Chemistry, Volume 5 (February 2015), published by Elsevier.

    "Characterization of hydraulic fracturing flowback water in Colorado: Implications for water treatment" by Yaal Lester, Imma Ferrer, E. Michael Thurman, Kurban A. Sitterley, Julie A. Korak, George Aiken and Karl G. Linden (doi: 10.1016/j.scitotenv.2015.01.043). The article appears in Science of the Total Environment, Volumes 512-513 (15 April 2015), published by Elsevier.

  • You Are What You Eat: Keep Your Drinking Water and Food Contaminant-free

    Public water systems undertake various measures in order to deliver safe and potable drinking water to households. These include chemical treatment and filtering processes to eradicate a variety of water contaminants. However, not only do some pollutants survive the treatment process, but during the water cleansing operation, chemical additives may add other contaminants to the water, which can be harmful to our health. If your household water supply originates from a well, borehole, or natural spring, there is a good chance that it may be contaminated with environmental pollutants that can enter the water source by leaching or with water runoff. Many private water sources do not undertake regular testing of the water quality, and therefore filtration with a high quality water filter is recommended to be sure that your water is safe to drink. Your water will not only be healthier, it will be clearer, fresher, tastier, and generally far more appetizing to drink.


    Choosing a Water Filter

    There are several types of water filters available on the market, which can be confusing. We recommend a good quality home water filter that is able to remove a wide range of potential toxins (chlorine, chloramines, bacteria, pharmaceuticals, etc) in a variety of situations (for example for daily use at home, on holiday, and in emergencies), and which has an adequate capacity to supply the daily needs of your family.

    Effects of Water Contaminants to Children’s Health

    Children have weaker immune systems compared to adults, as they are still developing. This makes them more vulnerable to common pollutants in water, such as chlorine, heavy metals and other chemicals that can pose health risks, which can include increased risk of cancer, learning difficulties, and gastrointestinal upsets. Drinking water with high levels of lead is known to negatively effect brain development in children, while nitrates present in unfiltered water can pose a severe health risk to your children by limiting oxygen absorption that can cause blue baby syndrome. Keep your children safe from these toxins by removing water contaminants through proper filtration of all water that is used for cooking, drinking, food preparation, or for mixing baby formula.

    Using Filtered Water for Preparing and Cooking Meals

    Since water is also used when preparing food, it is important to use clean, uncontaminated water when cooking or washing fruits and vegetables. Some foods, such as dried beans and lentils, also need to be soaked in water during their preparation before they are used in dishes like pasta and casseroles. Since they are rich in protein, legumes are widely used as a healthy substitute for meat by many vegetarians. Without a clean and safe supply of water to prepare our food, there is a good chance that good healthy foods may become contaminated while preparing meals.

    Boiling water kills most bacteria, but not all. Some bacteria present in water can withstand extreme temperatures and may survive to contaminate food boiled in the water, especially when not boiled for very long. Other water contaminants, such as heavy metals, industrial chemicals, and other toxic chemicals, cannot be removed by boiling. This must be taken into consideration especially for meals that are made up largely of water, for example soup. Some dishes absorb water while they cook, for example pasta and rice, and will absorb any pollutants present in the water as well.

    As we all want our food to taste as natural and wholesome as possible rather than of chlorine or other chemicals.  Using a water filter in the kitchen will ensure that you are providing your family with only the healthiest, great tasting cuisine. Always bear in mind that you are what you eat (and drink).

  • Don't Just Go Green, Go Blue Too!

    Everybody that cares for the environment is trying to go green these days. We keep tabs of our carbon footprint, recycle our waste, and try and be as energy-efficient as we can. We do this to minimize our impact on the environment, in the hope that we can collectively make a difference over time.

    There is a lot of focus on carbon emissions at the moment, and the impact of these emissions on global warming and climate change. We are encouraged to do our bit to help reduce these emissions – and many people do. We can measure our carbon footprint with online carbon footprint calculators. Corporate organizations can even purchase carbon credits – these funds are used to plant trees or fund green energy projects to offset the carbon footprint of these companies. But very little emphasis is placed on conserving water – a vital component of all living organisms on earth.


    Water is our most precious commodity – every plant and animal living on the planet requires water for its survival – humans are no exception. It is also a commodity that is used in every product that we eat or drink. Every steak, egg or plate of chips that we consume, took quantities of water to cultivate. The same goes for drinks, whether it is freshly squeezed orange juice, a can of soda, or a glass of chardonnay. Yet, it is a commodity that is very often taken for granted.

    We flush toxic waste into our rivers; allow our groundwater to become contaminated with countless contaminants including phosphates and nitrates from fertilizers, animal wastes and sewage; pesticides from runoff and arial drift; and many other contaminants, such as pharmaceuticals, plastics, and chemicals, enter water courses to contaminate our precious water reserves. The pollutants flow to the sea, where they cause further environmental damage. While many people are aware of the common forms of water pollution, a less known fact is that we pollute our water during seemingly harmless recreation activities – boating, fishing, and even swimming and surfing. Besides the obvious pollutants that enter water during these activities, toxins from sunscreens are another source of pollutants that enter water while we have fun in the sun. Sunscreens have been implicated as a primary cause of coral bleaching, which is destroying coral reefs in oceans around the world.

    However, with the help of some handy online tools, we can now calculate our water footprint, and can even purchase credits to offset this footprint, in much the same manner as we can calculate our carbon footprint using a carbon footprint calculator, and purchase carbon credits to offset our carbon footprint.

    Aquatrail Calculator

    The Acquatrail calculator, developed by Marine Positive, determines our aquatic footprint by measuring an array of different pollutants, including liquids, solids and gases that enter the aquatic environment through our aquatic activities. It then converts this to a monetary figure that we can pay to offset this footprint. It has two calculators, one for corporations, and one for individuals. The funds generated are used to support aquatic restoration projects around the world through the Going Blue Foundation, who strives to improve the quality of both freshwater and marine ecosystems through a range of rehabilitation projects.

    While this provides a mechanism to offset our bad deeds, it would be far better for the environment if we took the time to consider the consequences of our actions, and take preventative measures to reduce our environmental impact, rather than trying to offset it by funding restoration projects.

    What you can do:

    * Use natural soaps and detergents
    * Use a scientifically proven eco-friendly sunscreen
    * Don't flush pharmaceuticals, hormone/birth control pills, or other over the counter drugs
    * Try to reduce the amount of shampoo and conditioner you use when you wash your hair
    * Try to wash your car less often, and use less detergent when you wash it

    If everyone does their bit to reduce their aquatic footprint or 'acquatrail', we will be able to gradually reduce our environmental impact on our rivers, lakes and oceans. So, if you have already made the effort to go green, it's now time to go blue too.

  • High Levels of Methane Recorded in Pennsylvanian Stream

    Using a newly developed stream-based environmental monitoring system, researchers from the US Geological Survey (USGS) and Penn State University found methane at high levels along a stretch of a Pennsylvanian stream situated in close proximity to the site of a recently reported shale gas leak. This environmental monitoring system could potentially be of great value as a screening tool for conducting environmental assessments of the impacts associated with extracting shale gas by hydraulic fracking.


    After analyzing several water samples collected from Sugar Run, a stream flowing through Lycoming County, the scientists found evidence of methane in groundwater inflows similar to that found in natural gas. The findings were recently published in Environmental Science and Technology.

    Susan Brantley, a professor of geosciences at Penn State and co-author of the paper, finds it startling that after monitoring 15 streams, one instance of shale gas degassing has already been observed that could legitimately be explained by a known gas well leak sited nearby.

    After finding high concentrations of methane in Sugar Run, the researchers were also informed that several surrounding domestic water wells had reportedly been contaminated due to a defective cement casing of a nearby shale gas well.

    Upon conducting further analyses on the methane in the stream, the authors found characteristics that were common to that of leaking shale gas well. Unfortunately, as the researchers do not have access to baseline water samples from Sugar Run, they are unable to prove that the methane in the stream originates from the leaking gas well. However, the findings show how stream monitoring can be used as an efficient and effective method of monitoring the environmental impacts of fracking.

    "We hope this new technique developed by the USGS can now be used as a way of monitoring stray gas not only when it gets into drinking water, but when it gets into streams, which are much easier to access than homeowner wells," said Brantley. "In addition, streams collect water from nearby areas and may be very cost effective waters to target for monitoring because they integrate over larger land areas."

    Monitoring has up until now been largely restricted to water wells that supply domestic drinking water. But according to the researchers, because water wells can be spread out, particularly in rural settings, this limits the effectiveness of assessing the real impact of gas drilling operations. Water (and the chemicals in them) flows into streams from watersheds; thus sampling the streams enables us to detect leaks that would otherwise be impossible to trace.

    Journal Reference:

    Victor M. Heilweil, Paul L. Grieve, Scott A. Hynek, Susan L. Brantley, D. Kip Solomon, Dennis W. Risser. Stream Measurements Locate Thermogenic Methane Fluxes in Groundwater Discharge in an Area of Shale-Gas Development. Environmental Science & Technology, 2015; 150330072215005 DOI: 10.1021/es503882b

  • New Research Shows BPA can Negatively Affect Reproduction In Fish for Three Generations

    ** Bisphenol A, commonly known as BPA, is a chemical compound that is widely used in many everyday consumer products

    ** Researchers have found that when fish are exposed to endocrine-disrupting chemicals such as BPA, the adverse impacts remain in effect for up to 3 generations

    ** Findings showed a 30% decrease in the fertilization rate of fish two generations after exposure and a 20% reduction after three generations

    Bisphenol A, commonly known as BPA, is a chemical compound that is widely used in many everyday consumer products, including water and soft drink bottles, linings of metal food and beverage cans, as well as dental composites. Unfortunately, these and other contaminants typically end up in our freshwater systems where they can have profound ecological effects.

    Now, researchers from the University of Missouri-Columbia and the U.S. Geological Survey (USGS) have found that when fish are exposed to endocrine-disrupting chemicals such as BPA, the adverse affects of these contaminants are not only passed on to their offspring, but also onto their offspring's offspring, and their offspring too. Consequently the adverse impacts of BPA remains in effect for up to three generations.


    BPA is a known hormone disruptor that mimics the functions of natural hormones in both humans and animals. Fish and other aquatic species are typically exposed to these chemical contaminants during critical stages of their development, and in some cases may be exposed throughout their entire life cycle.

    According to lead author, Ramji Bhandari, an Assistant Professor of Biological Science at the University of Missouri who is a visiting scientist at the USGS, "this study shows that even though endocrine disruptors may not affect the life of the exposed fish, it may negatively affect future generations."

    Bhandari together with fellow research scientists Frederick vom Saal, a Professor at the University of Missouri, and USGS research toxicologist, Don Tillitt, exposed medaka fish to BPA and other chemicals for a week during the embryonic development stage. The scientists then monitored their offspring for four generations. None of the future generations were exposed to BPA or other chemicals. While there was no evidence of reproductive abnormalities in the first two generations of offspring, the scientists found the rate of fertilization to be lower, and embryo mortality higher, in future generations.

    Bhandari explains that the medaka fish was selected for this study due to their shorter generations, which made it the perfect candidate for the research study at hand. "Findings showed a 30% decrease in the fertilization rate of fish two generations after exposure and a 20% reduction after three generations. If those trends continued, the potential for declines in overall population numbers might be expected in generations far removed from the initial exposure."

    According to co-author,Don Tillet: "This study examined concentrations of BPA and other chemicals that are not expected to be found in most environmental situations. However, concern remains about the possibility of passing on adverse reproductive effects to future generations at lower levels."

    As BPA is known to have reproductive and other ill effects on humans, take precautions to protect yourself and the future generations of your family by ensuring the water you drink is free from BPA and other chemical contaminants. Berkey Water Filters are BPA free, and the Black Berkey filter elements that are fitted in the upper filter chamber have been proven to remove BPA from drinking water to >99.9%.

    Journal Reference

    Ramji K. Bhandari, Frederick S. vom Saal, Donald E. Tillitt. Transgenerational effects from early developmental exposures to bisphenol A or 17α-ethinylestradiol in medaka, Oryzias latipes. Scientific Reports, 2015; 5: 9303 DOI: 10.1038/srep09303

  • What Is Aluminum Oxide?

    Aluminum Oxide is media that is used in the Berkey PF line of filters that remove fluoride from the water. This article provides some additional information and insight into what exactly aluminum oxide (or alumina) actually is.

    Aluminum Oxide is an inert compound of aluminum and oxygen and has been utilized in removing fluoride from water since 1936. It is a naturally occurring, non-toxic, and also known as corundum. Rubies and Sapphires are an example of gem quality corundum. The research scientist Corrin (1963a; 1963b) noted that aluminum reacts with water but is not able to do so when coated with inert aluminum oxide. Aluminum oxide is no more toxic or water-soluble than are rubies and sapphires.

    The fact that alumina is a compound of aluminum and oxygen should not be cause for concern as the properties of the compound differ greatly from the plain components. For example, pure aluminum reacts so readily with water that, according to the laws of chemistry, the aluminum shell of an airplane should actually dissolve in the rain.  However, when aluminum is placed in the atmosphere, a thin layer or aluminum oxide forms on the metal surface and acts like a protective, rust-resistant shield.  Aluminum oxide is the most stable form of aluminum known and it is not soluble in water. An analogy would be table salt (NaCl), a compound of sodium and chlorine, each by themselves a harmful substance, but together is something the human body needs. Likewise, both oxygen and hydrogen are highly flammable, yet a compound of both creates water (H20) which is used to extinguish fire. As such, Aluminum oxide was taken off the United States Environmental Protection Agency's chemicals lists in 1988.

    When water molecules come in contact with aluminum oxide, the aluminum and oxygen atoms on the surface move apart -- in some cases separating by more than 50 percent compared to their normal molecular positions. As a result, when the outer layer of aluminum oxide gets hydrated or wet, its structure changes just enough to become chemically inert and thus unable to react rapidly with additional water molecules or atmospheric oxygen. This change in molecular structure is why aluminum oxide metal resists corrosion.


    There are no known bodily functions that react with aluminum oxide, hence it has excellent biocompatibility. Aluminum oxide is a well-proven, biocompatible ceramic that has been used as a dental porcelain pigment for some 60 years and as a ceramic restoration substructure for 25 years. It has a variety of orthopedic uses such as hip and knee joints where it has demonstrated excellent biocompatibility over the long term.

    Aluminum oxide is utilized in sunscreen and cosmetics such as blush, lipstick, nail polish, and many types of sandpaper. It is a major component of the cue tip "chalk" used in billiards and the powder is used in some CD/DVD polishing and scratch-repair kits. Its polishing qualities are also why it is used as a base in toothpaste. Some other applications include use as a dosimeter for radiation protection for its optically stimulated luminescence properties, in addition to insulation for high-temperature furnaces are often manufactured from aluminum oxide.


    When laboratories test for metal contamination in water it is first necessary to break apart the oxidized metal ions from their oxygen component. Then an ion count is taken. This is the same for Aluminum oxide. The oxygen is separated from the pure aluminum molecules so that the aluminum ions can then be counted. It is for this reason that laboratory tests do not distinguish between aluminum oxide and pure aluminum in their test water. In other words, such tests generate a false positive by separating the aluminum from the oxygen and then reporting the amount of pure aluminum in the sample.

    However, as illustrated above, pure aluminum and aluminum oxide have vastly different characteristics. Pure aluminum is water-soluble, it is highly reactive and it is associated with negative health effects. By contrast aluminum oxide is not water-soluble, is inert, very stable, and not associated with any known negative health effects.

    Physical constants of inorganic compounds, in: David R. Lide (Ed.) CRC Handbook of Chemistry and Physics. Boca Raton: CRC Press, 1994.

  • Chlorine Treatment of Wastewater May Contribute to Antibiotic Resistance

    ** Chlorine is a chemical commonly used to disinfect wastewater at sewage treatment plants

    ** Preliminary studies show that chlorine treatment at sewage plants may promote the development of new strains of antibiotics

    ** Results showed that when doxycycline was exposed to chlorine in treated wastewater, the antibiotic properties of their wastewater samples increased

    ** Strong recommendation for better methods to remove pharmaceuticals at treatment plants required, in addition to education regarding alternate means of pharmaceutical disposal

    Chlorine, a chemical that is commonly used to disinfect wastewater at sewage treatment works, may fail to completely remove pharmaceuticals from wastewater that enters these plants. Consequently, trace levels of pharmaceuticals, including drugs, are continually discharged into our waterways from wastewater treatment plants. Now, scientists report that preliminary studies show that chlorine treatment at sewage plants may promote the development of new strains of antibiotics, that could then also be released into the environment where they can in turn potentially promote antibiotic resistance.

    Graduate student Nicole Kennedy measures the antibiotic activity of various samples in the lab. Graduate student Nicole Kennedy measures the antibiotic activity of various samples in the lab.

    The findings, which were presented at an American Chemical Society (ACS) Chemistry of Natural Resources exhibition being held over the course of this week, suggest that wastewater treatment facilities need to re-evaluate the methods they use to treat and disinfect wastewater prior to discharge.

    "Pharmaceuticals that get out into the environment can harm aquatic life, making them react slowly in the wild and disrupting their hormone systems," explains Olya Keen; adding that when organisms are exposed to more antibiotics -- even when levels are low -- antibiotic resistant microbes can develop, which can ultimately result in antibiotics being less effective at fighting human bacterial infections.

    "Treated wastewater is one of the major sources of pharmaceuticals and antibiotics in the environment," says Keen. "Wastewater treatment facilities were not designed to remove these drugs. The molecules are typically very stable and do not easily get biodegraded. Instead, most just pass through the treatment facility and into the aquatic environment."

    But apart from their inability to remove all pharmaceuticals from sewage, wastewater treatment plants that use chlorine during the disinfection process may actually further promote the formation of new strains of antibiotics in the water that is discharged. Keen, together with her research team from the University of North Carolina at Charlotte, conducted a series of laboratory experiments to test this theory. The results showed that when doxycycline -- an antibiotic that is widely used across America -- is exposed to chlorine in treated wastewater, the antibiotic properties of their wastewater samples increased.

    "Surprisingly, we found that the products formed in the lab sample were even stronger antibiotics than doxycycline, the parent and starting compound," Keen explains. The researchers are in the process of identifying the properties of these "transformation products", and are particularly interested in determining if these compounds are new, as yet unidentified antibiotics.

    Keen suggests that for now, reducing the amount of pharmaceuticals that enter a wastewater treatment facility may be the best, if not only, solution to this problem. However, because disposal of pharmaceutical products is currently unregulated, she proposes that people should be encouraged to collect and incinerate unused drugs and other pharmaceutical products rather than simply flushing them down toilet or throwing them out with the garbage, as both these scenarios can result in increased environmental exposure, ultimately contributing to antibiotic resistance.

    Furthermore, this research also has implications for drinking water treatment facilities, many of which disinfect drinking water with chlorine during the treatment process. For chlorine to be effective at purifying drinking water, it needs to remain in the water distribution pipe network for hours. This prohibits the growth of microbes, but it also gives the chlorine plenty of time to interact with any pharmaceutical drugs that may be present in the water, and this interaction could encourage the formation of new antibiotic strains.

    Olya Keen, Ph.D.
    University of North Carolina at Charlotte
    9201 University City Blvd.
    Charlotte, NC 28223-0001
    Phone: 704-687-5048

  • Study Identifies First Human Population Adapted to Arsenic

    ** Argentina, scientists have identified the first known humans adapted to cope with high levels of arsenic

    ** Arsenic occurs naturally in rocks and soils and can leach into groundwater

    ** Scientists they did not know how populations could adapt to this toxin

    ** The adaptation is based on the rise in frequency of nucleotide variants helping metabolize arsenic faster

    ** Nucleotide variants observed in a sample of mummified women from approximately 7,000-10,000 years ago

    High up in the Andes mountain range of Argentina, scientists have identified the first known human population that is uniquely adapted to cope with the high levels of the toxic arsenic chemical found in their drinking water. Inhabitants of some areas of the mountainous Andes have been exposed to high concentrations of the naturally occurring arsenic for centuries.

    Arsenic occurs naturally in rocks and soils and can leach into groundwater that provides a source of drinking water to communities. Scientists know that arsenic occurs naturally, and that is poses a health risk to people exposed to it over long periods. However, until now, they did not know how populations such as this could adapt to this toxin to enable them to tolerate the potentially lethal killer chemical.

    Arsenic Poisoning Arsenic Poisoning Shown On The Skin

    In a study that was recently published online in Molecular Biology and Evolution, a team of Swedish researchers, led by Karin Broberg, a professor at the Karolinska Institutet, Uppsala University, conducted a genome wide survey of a sample group comprising 124 Andean women, looking at their ability to metabolize the chemical arsenic. After analyzing urine samples from the women, the researchers made a startling discovery. According to the research report: 'The study pinpointed a key set of nucleotide variants in a gene, AS3MT, which were at much lower frequencies in control populations from Columbia and Peru.'

    However, a mummified hominid that was recently excavated from the region was found to have high levels of arsenic in hair samples tested. Based on age analysis on the mummy, the scientists estimate the rise in frequency of these nucleotide variants observed in the women sampled in the study occurred relatively recently -- approximately 7,000-10,000 years ago.
    The results show how human populations are able to adapt to their environment of time to ensure their survival. This particular Andean population adapted to the environmental effects of arsenic by developing an increase in the frequencies of nucleotide variants that offer protection against this toxin.

    According to the researchers: "The set of AS3MT nucleotide variants, harbored on chromosome 10, were distributed worldwide, with the highest frequencies in Peruvians, Native Americans, Eastern Asia and Vietnam."

    They suggest that this localized adaptation may have developed as an evolutionary response to the severe adverse health effects suffered by the population due to arsenic exposure in their drinking water, and the need for the body to metabolize arsenic faster if they were to survive.

    This population is not the only one in the world that is exposed to toxic arsenic in their drinking water. A study conducted in 2007 found that more than 137 million people from over 70 countries worldwide, including some areas of the US, are likely affected by arsenic poisoning as a result of their drinking water being contaminated. The limit for arsenic in drinking water as recommended by the World Health Organization is 0.01 mg/L, or 10 parts per billion (ppb), however studies have shown that consuming drinking water with arsenic levels as low as 0.00017 mg/L (0.17 ppb) over a prolonged period can cause arsenicosis, or arsenic poisoning.

    Considering that this study suggests it takes thousands of years for local populations to adapt to arsenic by developing mechanisms to eliminate arsenic from the body, this is not going to help individuals cope in the short term. Thankfully we can take steps such as water filters to eliminate arsenic from our drinking water before it enters our bodies.

    Journal Reference

    C. M. Schlebusch, L. M. Gattepaille, K. Engstrom, M. Vahter, M. Jakobsson, K. Broberg. Human Adaptation to Arsenic-Rich Environments. Molecular Biology and Evolution, 2015; DOI: 10.1093/molbev/msv046

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