Shrimp’s Dirty Secrets: Why America’s Favorite Seafood Is a Health and Environmental Nightmare

by Jill Richardson

Water News in a Nutshell.

 

In a Nutshell: America’s favorite seafood is both farmed and harvested; neither way works very well for the environment. Exactly how to eat shrimp “ethically” is not clear.  Shrimp is, furthermore, not a health food, not to mention that it’s a pretty gross thing to be swallowing. 

Americans love their shrimp. It’s the most popular seafood in the country, but unfortunately much of the shrimp we eat are a cocktail of chemicals, harvested at the expense of one of the world’s productive ecosystems. Worse, guidelines for finding some kind of “sustainable shrimp” are so far nonexistent.

In his book, Bottomfeeder: How to Eat Ethically in a World of Vanishing Seafood, Taras Grescoe paints a repulsive picture of how shrimp are farmed in one region of India. The shrimp pond preparation begins with urea, superphosphate, and diesel, then progresses to the use of piscicides (fish-killing chemicals like chlorine and rotenone), pesticides and antibiotics (including some that are banned in the U.S.), and ends by treating the shrimp with sodium tripolyphosphate (a suspected neurotoxicant), Borax, and occasionally caustic soda.

Upon arrival in the U.S., few, if any, are inspected by the FDA, and when researchers have examined imported ready-to-eat shrimp, they found 162 separate species of bacteria with resistance to 10 different antibiotics. And yet, as of 2008, Americans are eating 4.1 pounds of shrimp apiece each year — significantly more than the 2.8 pounds per year we each ate of the second most popular seafood, canned tuna. But what are we actually eating without knowing it? And is it worth the price — both to our health and the environment?

Shrimp rank way ahead of second-place tuna as America’s seafood choice. You might prefer not to know where it comes from.

Understanding the shrimp that supplies our nation’s voracious appetite is quite complex. Overall, the shrimp industry represents a dismantling of the marine ecosystem, piece by piece. Farming methods range from those described above to some that are more benign. Problems with irresponsible methods of farming don’t end at the “yuck” factor as shrimp farming is credited with destroying 38 percent of the world’s mangroves, some of the most diverse and productive ecosystems on earth. Mangroves sequester vast amounts of carbon and serve as valuable buffers against hurricanes and tsunamis. Some compare shrimp farming methods that demolish mangroves to slash-and-burn agriculture. A shrimp farmer will clear a section of mangroves and close it off to ensure that the shrimp cannot escape. Then the farmer relies on the tides to refresh the water, carrying shrimp excrement and disease out to sea. In this scenario, the entire mangrove ecosystem is destroyed and turned into a small dead zone for short-term gain. Even after the shrimp farm leaves, the mangroves do not come back.

A more responsible farming system involves closed, inland ponds that use their wastewater for agricultural irrigation instead of allowing it to pollute oceans or other waterways. According to the Monterey Bay Aquarium’s Seafood Watch program, when a farm has good disease management protocols, it does not need to use so many antibiotics or other chemicals.

One more consideration, even in these cleaner systems, is the wild fish used to feed farmed shrimp. An estimated average of 1.4 pounds of wild fish are used to produce every pound of farmed shrimp. Sometimes the wild fish used is bycatch — fish that would be dumped into the ocean to rot if they weren’t fed to shrimp — but other times farmed shrimp dine on species like anchovies, herring, sardines and menhaden. These fish are important foods for seabirds, big commercial fish and whales, so removing them from the ecosystem to feed farmed shrimp is problematic.

Additionally, some shrimp are wild-caught, and while they aren’t raised in a chemical cocktail, the vast majority is caught using trawling, a highly destructive fishing method. Football field-sized nets are dragged along the ocean floor, scooping up and killing several pounds of marine life for every pound of shrimp they catch and demolishing the ocean floor ecosystem as they go. Where they don’t clear-cut coral reefs or other rich ocean floor habitats, they drag their nets through the mud, leaving plumes of sediment so large they are visible from outer space.

After trawling destroys an ocean floor, the ecosystem often cannot recover for decades, if not centuries or millennia. This is particularly significant because 98 percent of ocean life lives on or around the seabed. Depending on the fishery, the amount of bycatch (the term used for unwanted species scooped up and killed by trawlers) ranges from five to 20 pounds per pound of shrimp. These include sharks, rays, starfish, juvenile red snapper, sea turtles and more. While shrimp trawl fisheries only represent 2 percent of the global fish catch, they are responsible for over one-third of the world’s bycatch. Trawling is comparable to bulldozing an entire section of rainforest in order to catch one species of bird.

Given this disturbing picture, how can an American know how to find responsibly farmed or fished shrimp? Currently, it’s near impossible. Only 15 percent of our total shrimp consumption comes from the U.S. (both farmed and wild sources). The U.S. has good regulations on shrimp farming, so purchasing shrimp farmed in the U.S. is not a bad way to go. Wild shrimp, with a few exceptions, is typically obtained via trawling and should be avoided. The notable exceptions are spot prawns from British Columbia, caught in traps similar to those used for catching lobster, and the small salad shrimp like the Northern shrimp from the East Coast or pink shrimp from Oregon, both of which are certified as sustainable by the Marine Stewardship Council. However, neither are true substitutes for the large white and tiger shrimp American consumers are used to.

The remaining 85 percent came from other countries and about two-thirds of our imports are farmed with the balance caught in the wild, mostly via trawling. China is the world’s top shrimp producer — both farmed and wild — but only 2 percent of China’s shrimp are imported to the U.S. The world’s number two producer, Thailand, is our top foreign source of shrimp. Fully one third of the shrimp the U.S. imports comes from Thailand, and over 80 percent of those shrimp are farmed.

The next biggest sources of U.S. shrimp are Ecuador, Indonesia, China, Mexico, Vietnam, Malaysia and India. Together, those countries provide nearly 90 percent of America’s imported shrimp. Interestingly, Ecuador’s shrimp industry exists almost entirely to supply U.S. demand, with over 93 percent of its shrimp coming up north to the U.S. The vast majority of those shrimp (almost 90 percent) are farmed. Sadly, shrimp production is responsible for the destruction of 70 percent of Ecuador’s mangroves. Farming practices in other countries range from decent to awful, but there’s currently no real way for a consumer to tell whether shrimp from any particular country was farmed sustainably or not.

Geoff Shester, senior science manager of Monterey Bay’s Seafood Watch, says that ethical shrimp consumption is a chicken and egg problem. On one hand, the solution is for consumers to show demand for responsibly farmed and wild shrimp by eating it but on the other hand, ethical shrimp choices are not yet widely available. Seafood Watch is working with some of the largest seafood buyers in the U.S. to help them buy better shrimp, but it’s currently a major challenge.

The first challenge is that labeling and certification programs do not yet exist to identify which farmed shrimp meet sustainable production standards. The second challenge is that even when such programs are in place, the U.S. demand will likely greatly exceed their supply.

Shester’s advice to consumers right now is “only buy shrimp that you know comes from a sustainable source. If you can’t tell for sure, try something else from the Seafood Watch yellow or green lists.” Knowing that many will be unwilling to give up America’s favorite seafood, he advocates simply eating less of it and keeping an eye on future updates to the Seafood Watch guide to eating sustainable seafood.

Jill Richardson is the founder of the blog La Vida Locavore and a member of the Organic Consumers Association policy advisory board. She is the author of Recipe for America: Why Our Food System Is Broken and What We Can Do to Fix It..

Source:  Alternet.

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Neeri scientist treats contaminated water using plant waste

By Snehlata Shrivastav

Water News in a Nutshell.

 

In a Nutshell: Researchers in India have developed a highly effective way of removing heavy metals from water using plant waste materials like orange peel and rice husks. 

NAGPUR: Most people in rural India still do not have access to potable drinking water.Treatment of water to remove pollutants like heavy metals and disease causing microorganisms using low cost technologies and making it available to masses still remains a big challenge for the government. However, scientists across the country have been working to devise cheap and effective technologies for water purification.As a part of this effort, scientists at the water technology management division (WTMD) of National Environmental Engineering Research Institute (Neeri) has developed a technology to convert contaminated water into potable by removing heavy metals in it even at extremely low concentrations. The technology, which uses locally available plant waste material like orange peel, rice husk and wild nuts, is extremely low cost, effective and viable.Neeri director Satish Wate, who has been instrumental in convincing his scientists to take up projects based on societal problems, sees water as a priority area for the institute. “We do work on high end technologies and projects for the corporate sector but solving common man’s problems is our first goal,” he said.Head of WTMD division Pawan Labshetwar, who has been supervising the project, says removal of both inorganic and organic contaminants from water has been an integral part of Neeri research.
This particular process has been developed by a young fellow scientist Manish V Rahate who basically got the idea of utilizing local plant waste from his guide Shyam Shukla at Lamar University in USA while pursuing his Master’s degree. Rahate also received support from VA Mahisalkar from Visvesvaraya National Institute of Technology (VNIT). He says though his process has given excellent results at laboratory level, it needs to be scaled up for community use.

“We have tried it for a minimum of 1000 litres of water and the plant waste material can be reused. The three-step process costs just Rs5-6 per 1000 litres. In the first step, the heavy metals present in the lowest possible concentration are adsorbed using plant waste. Second step uses sand and coal powder to filter other contaminants and makes water more palatable. Last step uses a specially developed metal oxide which acts as an oxidant and disinfects water from organic pollutants-micro-organisms like bacteria,” Rahate said.

Since plant materials are rich in substances called as pectin and lignin which are good adsorbents of heavy metals, the researchers have chosen them for removal of arsenic and iron. The process uses 12 different plant materials like rice husk powder, dried and powdered wild nuts, mango leaves, banana and orange peels. These powders form the first layer of the filter. Rahate has labelled his process as L3 (low cost, low technology and locally available) and KISS (Keep it simple and sweet). He would be presenting his work at the international workshop for young environmental scientists titled ‘Urban water resources and risks’ to be held in June first week in Paris.

Rahate has already received the ‘Young water professional’ award for this process at an international conference held in January in Malaysia. “There is still a long way to go to make this process commercially available. But I am confident of making this happen very soon,” he said.

Source Reference: Times of India.

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New Requirements for Ballast Water Dumped by Ships

 

Editor’s Note:  The following is excerpted from Boston.com.  Go here for the full article.

 

TRAVERSE CITY, Mich. (AP) — The Environmental Protection Agency has issued new requirements for cleansing ballast water dumped from ships, which scientists believe has provided a pathway to U.S. waters for invasive species that damage ecosystems and cost the economy billions of dollars.

Commercial vessels are equipped with tanks that can hold millions of gallons of water to provide stability in rough seas. But live creatures often lurk in the soupy brews of water, seaweed and sediment. If they survive transoceanic journeys and are released into U.S. waters, they can multiply rapidly, crowding out native species and spreading diseases.

Ships are currently required to dump ballast water 200 miles from a U.S. shoreline. But under the new general permit released Thursday by the EPA, vessels longer than 79 feet — which includes an estimated 60,000 vessels — must also treat ballast water with technology such as ultraviolet light or chemicals to kill at least some of the organisms.

The new guidelines don’t apply to vessels staying within the Great Lakes, a decision that environmentalists criticized as leaving the door open for ships to ferry invasive species around the lakes.

The permit imposes international cleanliness standards that the Coast Guard also adopted in regulations it issued last year. The EPA said studies by its science advisory board and the National Research Council endorsed the standards, which limit the number of living organisms in particular volumes of water.

Environmental groups contend the limits should be 100 or even 1,000 times tougher, but industry groups say no existing technology can go that far.

The Three Basic Coal-Based Filter Carbons and Their Special Properties

The heart of most water filtration systems is filter carbon, usually called “granular activated carbon,” or GAC.   Activated carbon is the preferred treatment for a large percentage of  contaminants on the EPA’s list of monitored water issues.  Carbon is an effective treatment for a large percentage of chemical contaminants, including disinfectants like chlorine and chloramine, plus it is very effective at improving the aesthetic qualities of water like taste, odor and color.

Filter carbon is a manufactured product, but it starts from a natural source.  It can be made from any carbonaceous raw material.  Coconut shells are a common raw material used in carbon making, but by far the most common source material is coal.

Carbons made from lignite tend to have a large pore diameter. The pore diameter is measured by a property know to manufacturers as the “molasses number.”  The higher the molasses number the more suited the carbon is to remove colors from liquids.

Bituminous coal activated carbons have a broad range of pore diameters. Since these carbons have both a fine and wide pore diameter, they are well suited for general de-chlorination and the removal of a wider variety of organic chemical contaminants from water, including colors.

Because of its versatility, bituminous carbon is the most commonly used carbon for general water treatment.

In addition to the “molasses number,” qualities that are used to grade filter carbons are the so-called iodine number, the ash content, the abrasion number, the bulk density, the peroxide number, and the phosphorous content.  

Reference.

 

 

EPA’s Comprehensive Survey Finds Little Positive About the Condition of America’s Rivers and Streams

The Environmental Protection Agency (EPA) released the results of the first comprehensive survey looking at the health of thousands of stream and river miles across the country, finding that over half — 55 percent — are in poor condition for aquatic life.

“The health of our Nation’s rivers, lakes, bays and coastal waters depends on the vast network of streams where they begin, and this new science shows that America’s streams and rivers are under significant pressure,” said Office of Water Acting Assistant Administrator Nancy Stoner. “We must continue to invest in protecting and restoring our nation’s streams and rivers as they are vital sources of our drinking water, provide many recreational opportunities and play a critical role in the economy.”

The 2008-2009 National Rivers and Stream Assessment reflects the most recent data available, and is part of EPA’s expanded effort to monitor waterways in the U.S. and gather scientific data on the condition of the Nation’s water resources, stated the release.

Findings of the assessment include:

– Nitrogen and phosphorus are at excessive levels. Twenty-seven percent of the nation’s rivers and streams have excessive levels of nitrogen, and 40 percent have high levels of phosphorus. Too much nitrogen and phosphorus in the water—known as nutrient pollution—causes significant increases in algae, which harms water quality, food resources and habitats, and decreases the oxygen that fish and other aquatic life need to survive. Nutrient pollution has impacted many streams, rivers, lakes, bays and coastal waters for the past several decades, resulting in serious environmental and human health issues, and impacting the economy.

– Streams and rivers are at an increased risk due to decreased vegetation cover and increased human disturbance. These conditions can cause streams and rivers to be more vulnerable to flooding, erosion, and pollution. Vegetation along rivers and streams slows the flow of rainwater so it does not erode stream banks, removes pollutants carried by rainwater and helps maintain water temperatures that support healthy streams for aquatic life. Approximately 24 percent of the rivers and streams monitored were rated poor due to the loss of healthy vegetative cover.

– Increased bacteria levels. High bacteria levels were found in nine percent of stream and river miles making those waters potentially unsafe for swimming and other recreation. 

– Increased mercury levels. More than 13,000 miles of rivers have fish with mercury levels that may be unsafe for human consumption. For most people, the health risk from mercury by eating fish and shellfish is not a health concern, but some fish and shellfish contain higher levels of mercury that may harm an unborn baby or young child’s developing nervous system.

EPA plans to use this new data to inform decision making about addressing critical needs around the country for rivers, streams, and other waterbodies. This comprehensive survey will also help develop improvements to monitoring these rivers and streams across jurisdictional boundaries and enhance the ability of states and tribes to assess and manage water quality to help protect our water, aquatic life, and human health. Results are available for a dozen geographic and ecological regions of the country.

Read the entire press release here.

The EPA Must Protect Our Water From Coal Pollution

by Mary Anne Hitt

Water News in a Nutshell.

 

In a Nutshell: We think of coal-fired power plants as one of our worst air polluters.  They are, but what isn’t so widely known is that they are also one of our worst water polluters. They dump more toxins into US lakes and rivers than any other industry, and a 28% increase is expected over the next 15 years.

Here’s a pretty shocking fact: While many of us know that coal-fired power plants create significant air pollution, it turns out they’re one of our biggest water polluters, too. In fact, as we’ve developed technologies that take more toxins like mercury out of coal plant smokestacks, that pollution isn’t just disappearing. Much of it is ending up in the water, instead, and those pollution levels are on the rise. Fortunately, our Environmental Protection Agency can do something about it.

That’s right – the same power plants that are causing asthma and heart attacks with their soot and wrecking our climate with their carbon are also dumping tons of toxins into our waters. And without federal standards to safeguard our water, those plants will keep on sending toxic sludge into rivers and streams, where it threatens swimmers and boaters and anglers, poisons wildlife, wrecks ecosystems, and could even contaminate drinking water. The fouled waters pouring from coal plants are laced with arsenic, mercury, and selenium: toxins that build up in ecosystems and that are dangerous even in very small amounts.

If you’re a parent like me who loves to watch your child play in the local stream or lake, this information is infuriating and scary. The same goes if you’re a wildlife lover, or some who just enjoys the outdoors and believes our waterways should remain pristine.

Believe it or not, power plants dump more toxins into our rivers and streams than any other industry in the United States, including the chemical, plastic, and paint manufacturing industries. Your drinking water should be safe, because our cities and towns do a good job of filtering and cleaning it, but those in rural areas who rely on wells don’t have as much protection. Plus, our waterways, wildlife and ecosystems aren’t so lucky. Coal plants have caused nasty fish kills and their poison builds up in fishing lakes and reservoirs.

The problem’s only getting worse as coal plants get older. The Environmental Protection Agency (EPA) estimates that the amount of toxic wastewater from these plants is going to increase 28% over the next 15 years. That means more heavy metals and more toxic sludge in more streams and rivers. More contaminated rivers, more unhealthy streams, more poisoned wildlife.

Thankfully the EPA and President Obama can protect our waterways from this toxic wastewater. The rules governing coal plant water pollution – known as effluent limitation guidelines – are more than thirty years old, and just don’t deal with most of the toxins these plants dump into our water. The good news is that EPA is now on track to propose a vitally needed update to those standards. The new safeguards are due out in mid-April – but the coal industry is already trying to block them. We need to tell the EPA and President Obama right now – before it’s too late – to give us safeguards against toxic wastewater.

Clean water is too precious to wait another day.

Enough is enough. We need these safeguards, and we ultimately need to move beyond coal. Every step we take toward clean air and water helps keep our communities and our environment healthy.

It also takes us one step closer to powering the U.S. with clean energy, as our nation realizes that coal’s real cost — in climate destruction, toxic water, and unhealthy air — is simply too high.

Source: Huffington Post.

Gazette Fair Use Statement

Rainwater Falls from the Sky, But It Must Be Purified For Drinking

As water becomes scarce, rainwater collection systems are becoming increasingly popular.

After water is collected and stored for later use, water treatment is essential. This usually takes the form of filtering out large particles then treating for microbiological safety. If the water is contaminated with chemicals from its collection process (for example, roofing materials if the water is collected from a roof), then a good carbon filter should be added to the treatment.

Filtering for sediment can be either with cartridge filters or, if there is a lot to be filtered out, a backwashing filter that filters down to 10 microns or so.

After elementary filtration to remove particulate, it is critical that some form of disinfection be used. This can be:

Chlorination, the old standby, followed by carbon filtration to remove the chlorine.

Ultraviolet (UV), which is probably the most popular single rainwater treatment. The water must be very clean when it passes the UV lamp to assure complete disinfection. UV has the advantage of adding no chemicals to the water. It should be the last stage in the treatment process.

Ozonation is an excellent disinfectant, but is a bit more challenging for the homeowner from the technical viewpoint.

Ultrafiltration (UF) is gaining popularity in rainwater treatment. UF filters down to about 0.02 microns—enough to remove cysts, bacteria and viruses. Again, water must be pre-filtered before the UF membrane to protect it from premature clogging of the ultrafiltration equipment.

Rainwater, with only the minimal treatment described above, can provide extremely good water. Its mineral content (TDS: Total Dissolved Solids) is very similar to that of reverse osmosis water.

Reference Source:  The Pure Water Occasional.

The New Metal Gharat: A Simple Application of the Power of Water

A modern version of a traditional tool, the gharat, or small water-powered turbine, is part of an ecologically sustainable economic revolution that is taking place in some remote Indian villages in the Himalayas.

The traditional wooden water turbine, widely used at one time, has been on the decline because of its inefficiency and the cost of building and maintaining it.  Newer wheels, developed and popularized by a former botany professor named  Anil Joshi, have brought significant improvements to many remote areas of rural northern India.  Joshi launched a grass-roots movement to help Himalayan villagers stop using coal-intensive power and instead turn the region’s thousands of fast-flowing streams into personal mini hydro-electric power stations.

The new gharat, a water wheel with steel blades,  grinds grain, presses oil, and generates electricity for  remote villages where electricity is otherwise unavailable.  A single steel-bladed wheel can produce electricity at night for as many as 60 homes. Usually the small turbines are used to provide hydro power for small-scale industry by day and for generating electricity by night.

A Gharat in Action.


Water wheels are a centuries-old technology in the Himalayas, but one that was becoming obsolete until Joshi and an organization he founded three decades ago taught villagers to develop alternative livelihoods by modernizing the wheels and using them for traditional industry during the day and to provide electric power for village homes at night.

Improving the technology was key to Joshi’s strategy. The old water wheels were inefficient, taking a day to crush around 10 kilos (22 pounds) of wheat. Making a single wheel was a laborious process that required the wood from an entire pine or cedar tree. And environmental considerations had led to restrictions on tree-felling, which drove up the price of timber.

Joshi did much to improve the traditional gharats by fitting them with modern gears and ball bearings, but the main innovation was the introduction of steel for the turbine blades. Wooden wheels were liable to break when torrential monsoon rains washed rocks downstream, and repairing the blades was time-consuming and costly.

The most recent improvement has been the change to the horizontal turbine to replace the traditional vertical model.

Many of the hill streams which drive the small turbines come down with tremendous force and as much as 1/5 of the generative capability is lost by the crashing of the water into the turbine vertically. Much capacity is gained with the use of the horizontal turbine.

The redesigned gharat represents an exemplary use of simple resources to improve the world without destroying it. Using the free energy from the streams rather than diesel generators or nuclear power creates a clean, sustainable power source.

Reference: The Christian Science Monitor.

Environmental Superhero: Why Wastewater Treatment is Coming to Our Rescue

Water News in a Nutshell.

 By John Wycliffe

In a Nutshell: Wastewater treatment is a positive environmental force for it not only makes useless water useful but it takes waste, pollution, and toxins out of the environment. 

Where does the ‘sewage’ or wastewater go once you flush, wash off vegetables for cooking, and drain the bathtub?  What are the implications of efficient treatment in creating a better society and healthy environments for people in the United Kingdom?  The environment is looked after and treated by an unlikely superhero, wastewater treatment and management.

Without proper address, contamination occurs, instigated by metals, rain pollutants, oils, and urban-area runoff.  The health of people and the integrity of the environment demand efficient treatment methods.

What is Wastewater?

Sewage is a mixture of water stemming from kitchens, bathrooms, and toilets, combined with wastewater coming from industrial entities and road run-offs.  Treatment entails less filtering (less than 0.1 percent of wastewater is solid) but demands great attention and meticulous regard to an assortment of methods.

The Need for Treatment

Untreated water causes great harm to the environment and its inhabitants.  Proper wastewater management:

  • Safeguards the ecosystem, ensuring water that finds nature’s plants and animals are not depleted of rich oxygen due to biodegradation
  • Protects the ecosystem from eutrophication, a negative result of an abundance of nutrients present in water
  • Addresses water-borne pathogens that pose risks to people using waters related to public activities, such as swimming and canoeing
  • Clears obstructions to sewage flow and litter that can impact the environment (riverbed debris pose a fire hazard)
  • Ensures hotels, resorts, and all public places are not influenced by poor smells and limited usage

Benefits of Wastewater Treatment

Types and direction of water treatment take various courses depending on specific environments and sought end outcomes that are sought.  Workers seek to rid sewage of solids, excessive nutrients, metals, and pathogens.  Without the aid of water treatment processes:

  • Toxic agents and chemicals would negatively affect the well-being of wildlife and humans
  • Waste would find way into river streams and larger bodies of water, harming animals, plants, and the ecosystem
  • Particular environments would not enjoy the replenishing arrangement of recycled waters, preserving the land and recreational activities sought
  • Sewer ‘sludge’ would accumulate, creating mass sickness, marring plants and animals.

    Wastewater Treatment Tanks

The Future of Water Waste Management

The United Kingdom’s future is aligned with proper, present choices.  Waste management officials call for the peoples’ help, an example being the ‘Love Your River’ campaign, directing attention to the link between river and surrounding habitat health, hoping people take better care of their local rivers and neighborhoods.

Additionally, the UK has enacted (FOG) fats, oils, and grease disposal processes, ensuring pubs and restaurants properly rid the environment of collections.  Otherwise, FOGs stick to pipes and tunnels, solidifying into entities that can potentially obstruct sewer passageways, creating social complications and costing governments and municipalities a lot of money to remedy.

The next time you take a shower, flush a toilet, or leave the sink faucet running, think about what it takes to ensure the water keeps flowing without affecting your health and that of others.  Moreover, cogitate on the commitment paid to ridding rivers and flowing water of sludge and sewage-related debris.  It’s easy to forget sewage and proper water management is a production of a structured society; a lot of energy and devotion is placed upon maintaining and improving that infrastructure.

Author John Wycliffe is a researcher with an extensive background in chemistry. Her articles mainly appear on environmental blogs where she enjoys sharing her findings. Visit the chlorine analyser link for more details.

Source: Green Building Elements.

Gazette Fair Use Statement

 How Alum Is Used in Drinking Water Treatment, and What Are Alum’s Health Effects?

One of the first of the several steps that municipal water suppliers use to prepare water for distribution is getting it as clear and as particulate-free as possible.  To accomplish this, the water is treated with aluminum sulfate, commonly called alum, which serves as a flocculant.   Raw water often holds tiny suspended particles that are very difficult for a filter to catch.  Alum causes them to clump together so that they can settle out of the water or be easily trapped by a filter.  

Usually  a mixture of water with 48 percent filter alum  is injected into the raw incoming water at a rate of 18 to 24 parts per million. The alum promotes coagulation of fine particles which helps resolve problems of color as well a turbidity. If the process is given enough time to work and is applied properly, it not only corrects problems in the water but actually results in removing most of the aluminum used in the process.  

Although concern over the safety of treating water with aluminum has often been voiced, there is no evidence that aluminum in water, whether it comes from the aluminum sulfate used in treatment or from other sources, is a health issue. Actually, most aluminum that we take in does come from other sources.  One study showed that only between 0.4% and 1.0% of our lifetime intake of aluminum comes from alum used to prepare municipal water. Most aluminum intake is from aluminum that occurs naturally in foods, aluminum used in food packaging, and from products like deodorants and vaccines.

Water treatment for aluminum is normally not needed, but aluminum is easy to remove with reverse osmosis or distillation.

See also “Simple Facts about Aluminum.”