Posted on 20 July 2011.
Posted in What Is/Are...?Comments Off
Posted on 14 July 2011.
DDT, the abbreviation for dichlorodiphenyltrichloroethane, is a well-known chemical pesticide with a controversial history.
DDT does not naturally occur. Instead, it must be chemically synthesized. Because DDT has caused so much controversy, it has been marketed under several trade names, like Anofex, Chlorophenothane, Dicophane, and Neocidol. When ingested by insects, DDT causes spasms and eventually death. However, some mutated insects have developed a gene that has made them resistant to insecticides like DDT. When ingested by humans, DDT can disrupt our endocrine systems.
The chemist Othmar Zeidler first synthesized DDT in 1874. However, he was not aware that the chemical could work as an insecticide. Later, in 1939, the Swiss scientist Paul Hermann Muller discovered DDT’s insecticidal properties. He was awarded a Nobel Prize in 1948 for his discovery. DDT was first used as a pesticide during WWII, where it worked so well as an insect killer that some soldiers labeled it the “atomic bomb” of pesticides. After WWII, DDT was made available to farms, where it could be used on crops. It soon became the most popular insecticide.
In 1962, biologist Rachel Carson published a book called Silent Spring, a book that many credit with beginning the environmental movement. In Silent Spring, Carson questioned whether indiscriminately spraying DDT onto crops was harming the environment. She was the first scientist to truly critique the safety of releasing chemicals into the environment without knowing how they would impact us or our world. Carson worried that pesticides like DDT were harming the environment and causing cancer in humans. Largely because of Silent Spring’s popularity, the United States banned DDT’s agricultural usage in 1972.
After being banned, DDT is much less common today. Between 1950 and 1980, worldwide agriculture used over 40,000 tons of DDT each year. In 2009, however, only 3313 tons of DDT were produced, and they were produced mainly for the treatment of malaria, not for agricultural use. Environmentalists believe that the DDT ban has helped endangered species make comebacks, most notably the bald eagle.
Posted in The Global Water CrisisComments Off
Posted on 09 July 2011.
We usually think of water as being tasteless, odorless, and colorless. However, this is a misconception. In fact, we like our water to have a taste—in blind taste tests, we prefer tap water to distilled water. Most taste testers agree that water should have a taste, but that it shouldn’t stand out.
Several factors influence the taste of water. Tap water taste changes depending on where you live and the water treatment process in your area. We commonly associate municipal water with the slightly acidic taste of chlorine. Carbonation levels affect carbonated water’s taste. Greater amounts of carbon dioxide make the water taste more acidic—drinkers call this acidity “spritzy” or “sharp,” and may enjoy or dislike this taste based on their own personal preferences. Bottled water brands mislead consumers into thinking that bottled water tastes better than tap water: blind taste tests show that most consumers prefer tap water. When water is used as an ingredient, the water’s taste in turn affect affects the foods and drinks that it helps make.
We think of water as being tasteless, but subconsciously we are always judging its flavor. We consider water’s saltiness, its softness, its earthiness. When most people talk about tap water’s “taste,” they are really referring to its flavor. While taste is merely what one perceives with the tongue, flavor takes into account smell and touch, or mouthfeel, in addition to taste. Our 100,000 taste buds are assess the four basic stimuli of sweetness, sourness, bitterness and saltiness of all of the water that we drink. Most taste testers agree that water should have flavor, but shouldn’t stand out. Most taste testers also agree that water’s flavor is enhanced when we filter out chemicals like sulfur and chlorine.
All water molecules are made up of two hydrogen atoms combined with one oxygen atom. However, water’s taste nevertheless varies. The taste of water varies because water is a universal solvent. That is, water dissolves a little bit of everything it touches. As water travels, it picks up dissolved mineral traces from everything it touches, traces that affect the way the water tastes. This is why the taste of water varies depending on where it comes from.
Posted in TasteComments Off
Posted on 08 July 2011.
What is an isolation tank? You may have heard people talking about isolation tanks recently, but you may not know what they are yourself. An isolation tank is a lightless, soundproof tank in which a person floats in skin temperature salt water. Isolation tanks employ sensory deprivation as a tool for meditation and relaxation. Some consider isolation tanks a form of alternative medicine. Isolation tanks go by many names, such as float tanks, sensory deprivation tanks, and floatation baths.
Isolation tanks are designed to cut off all stimuli. The water in isolation tanks is filled with Epsom salt, which increases the water’s salinity and density, allowing users to float more easily with their faces above the water. Because the users’ ears float below the water, hearing is reduced. Other users use ear-plugs to further cut off sound. Users float with their arms by their sides, reducing skin sensation. To reduce smell, the water is treated as little as possible. The water temperature is carefully matched with the air temperature, cutting down one’s feeling of having a body boundary. In short, the isolation tank is designed to eliminate as many stimuli as possible.
People usually use the isolation tank while naked. While users can technically wear swimsuits, this is discouraged because the elastic on swimsuits can uncomfortably compress skin, producing extraneous negative stimuli. Because the water should be altered by external forces as little as possible, users must bathe before entering the tank. After their isolation tank session, users must bathe again to cleanse their skin of the Epsom salt. For this reason, a shower is usually installed in the same room as the tank. This allows the user can switch directly from the shower to the tank and the tank to the shower.
The isolation tank was created in 1954 by medical practitioner John C. Lilly. John C. Lilly, a trained psychoanalyst, wanted to experiment with sensory deprivation. Several theories about sensory deprivation were circulating in Lilly’s. These theories held that the brain could go to sleep if all stimuli were cut off to it. Lilly decided to test these theories with the isolation tank, an experimental environment that would isolate the individual from external stimulations. He used this experimental environment to study awareness and consciousness. Experimenters at other universities continue his studies today. What is an isolation tank? A relaxation technique whose benefits are still being researched today.
Posted in What Is/Are...?Comments Off
Posted on 02 July 2011.
Nowadays, after the growth of industries, clean drinking water doesn’t naturally occur. Scientists continually discover contaminants in fresh water sources and correlates between drinking contaminated water and health problems. Because we need water but it is impure, we have learned to treat water. However, the history of water filtration is not a recent one; water filtration began over 4000 years ago.
Some milestones in the history of water include the invention of the microscope, the advent of municipal water treatment, the use of chlorine to purify water, and the Clean Water Act of 1972.
The earliest recorded attempts to filter water date back to 2000 BC, to early Sanskrit writings of water purification methods. These methods include boiling water and filtering water through sand or charcoal filters. The Sanskrits’ biggest motive was to make water taste better, because they assumed that good-tasting water would also be clean. People didn’t yet realize that contaminated water caused disease, and they certainly couldn’t test for diseases in water.
In 1590, the Dutch glasses-makers Zaccharias and Hans Janssen invented the forerunner to modern-day microscopes. A century later, Anton van Leeuwenhoek, “the father of microscopy,” advanced the Janssens’ invention to the extent that scientists could now view tiny living particles in water that had previously been thought clean. In nineteenth-century London, city officials first linked cholera to bad water quality. John Snow, a British scientist, confirmed cholera bacteria in the Broad Street Pump’s water, proving that taste and visual clarity doesn’t prove water’s pureness. After this event, the British government insisted upon filtering city water, a precedent for municipal water systems. The British municipal water system cleaned water partly by treating it with chlorine.
In the 20th century, people increasingly agreed that every person has the right to clean water. The Clean Water Act (CWA) of 1972 made it a law that every city in the United States must have a water treatment plant. The CWA forced industrial plants to become environmentally friendly and renewed interest in water filtration, making clean water a national goal. Today the history of water continues as we strive to bring clean water to places that still need it.
Posted in Water UseComments Off
Posted on 01 July 2011.
The history of water treatment has been marked by slow, gradual discoveries that coincided with human development. While water filtration technology only became successful and widely used in the 20th century, the history of water treatment can be traced back to thousands of years ago.
Man has sought pure, clean water for as long as he has been on Earth. The earliest recorded mention of water filtration and purification can be found in Sanskrit writings from about 2000 B.C.E. These writings state that “impure water should be purified by being boiled over a fire…or it may be purified by filtration through sand and coarse gravel and then allowed to cool.” This demonstrates that even in some of the earliest civilizations the basics of water purification were known. There is also some evidence that the ancient Egyptians used wick siphons for water clarification. Later, following the tutelage of Hippocrates, the Greek and Roman empires used cloth bags and additives such as pounded barley to filter out bad tastes in water.
After Sir Francis Bacon renewed interest in filtration in 1627, a number of important scientific discoveries deeply affected the history of water treatment. Around 1690, Anton van Leeuwenhoek invented an early version of the modern microscope, which allowed scientists to more effectively study particles in water. Meanwhile, in Italy, Lucas Antonius Portius invented the first effective sand filtration system using multiple perforated compartments and large grains of sand. These two inventions allowed people in 19th century Britain to examine disease-causing bacteria in water and create one of the world’s first municipal water treatment systems.
In the early 1900s, English physicians discovered that chlorine was very effective in eliminating disease from water, and chlorination of public water systems began. The United States and other countries soon followed suit, and in 1972, the Environmental Protection Agency passed the Clean Water Act, requiring cities to filter public water. Today, amid growing concerns about the safety of water fluoridation and chlorination, individual households have begun to install filtration devices to taps, showerheads, and entire plumbing systems.
The history of water filtration is still being written. While individuals in America and other countries continue to improve the quality of household water, many people in developing countries lack the ability to properly filter their water. The challenge moving forward will be in improving water filtration for all of humanity.
Posted in SanitationComments Off
Posted on 27 June 2011.
Many readers may be wondering, “What are phthalates?” Phthalates are a group of petroleum-based chemicals that were originally developed to make plastics more flexible. Nearly all people in industrialized and developing countries carry varying amounts of phthalate compounds in their bodies. However, phthalates have also been found to disrupt hormones in animals and humans. Because we use plastics in virtually every part of our lives, we may limit our exposure to phthalates, but never completely eliminate it.
Once we understand what are phthalates, we must understand what they’re used for. Phthalates are chemicals that can be found in anything plastic. Food packaging, nail polish, vinyl tiling, garden hoses, shampoos and insect repellent all contain phthalates. In fact, the coveted “new car smell” is actually the smell of phthalates vaporizing as plastic parts are exposed to heat. Given our constant exposure to phthalates, it is unsurprising that these chemicals affect human health.
What are phthalates? Dangerous. Phthalates are hormone disruptors. Phthalate exposure in the womb shortens gestation, lowers male children’s sperm count and in female children causes endocrine problems that lead to premature breast development. This is especially worrying because, according to a 2000 study by the U.S. Centers for Disease Control, women of child-bearing age receive twenty times more phthalate exposure than any other segment of the population. The U.S. Environmental Protection Agency has regulated phthalates as water and air pollutants since 2005. In lab animals, phthalate exposure again lowers sperm count and also causes birth defects and testicular atrophy.
Although research has proven phthalates’ devastating health consequences for animals, research has not yet proven phthalates’ health consequences for humans to an extent that would sufficiently justify banning phthalates’ usage. However, you can lessen your phthalate exposure in several ways. Avoid products with artificial fragrances, as these products likely contain phthalates. Shop for personal care items that are labeled “phthalate-free.” If a product’s label lists di-n-butyl phthalate (DBP) or diethyl phthalate (DEP) among its ingredients, put it back on the shelf.
The Environmental Working Group (EWG) has published a list of 210 common household items that contain phthalates. This list can be accessed at their website and used as a guide to the products you should watch out for. The EWG also publishes a parents’ guide to phthalate-free childcare products.
Posted in What Is/Are...?Comments Off
Posted on 27 June 2011.
Chlorine is commonly used to disinfect our water. However, chlorine in water can also harm us. Because of this, we need to learn how to remove the chlorine in water, or how to entirely replace chlorine usage in our water treatment.
Chlorine is well-known and widely used to disinfect our water. Chlorine in water deactivates various pathogenic microorganisms (like bacteria or viruses), which cause illness. Authorities chlorinate public water supplies in order to kill the hazardous bacteria present in our water or water pipes. In addition to disinfecting water, chlorine is also used to disinfect various home and hospital areas and to bleach fabrics. We have used chlorine in water as a disinfectant for over two hundred years.
Although chlorine can disinfect our water, it can also hurt us if ingested. Chlorine in water can form into toxins called trihalomethanes (THMs); THMs correlate with diseases like asthma, eczema, bladder cancer, and heart diseases. Studies have shown that drinking large amounts of chlorinated tap water dramatically increases pregnant women’s risk of miscarriages and birth defects.
Carbon filters remove chlorine, THMs, and other harmful contaminants from our water. Additionally, while they produce the same excellent water quality that electronic filters produce, carbon filters are much cheaper. You can also remove chlorine and other contaminants from water without a home filtration system by placing water in an uncovered container and leaving it inside your refrigerator for twenty-four hours.
Although we need to disinfect our water, we don’t need to use chlorine to do so. Several Canadian and European cities are disinfecting their water using the ozone instead of chlorine. Some cities in the United States, like Las Vegas and Santa Clara, are also switching to this alternative. However, the easiest way to get rid of the chlorine in water is simply to filter it out.
Posted in The Global Water CrisisComments Off
Posted on 03 June 2011.
Your government knows that your water is contaminated, but may not be doing anything about it. The Environmental Protection Agency (EPA) created the Contaminant Candidate List (CCL) to monitor unregulated drinking water contaminants, like sodium. The contaminants on the CCL are chemicals that are known or expected to occur in public water systems. The EPA reviews the CCL to decide whether these unregulated chemicals should be regulated by the Safe Drinking Water Act. The EPA is currently reviewing the relationship between sodium and water.
Chemicals listed on the CCL are categorized into three groups, chemicals that should be researched, chemicals that require more data, and chemicals that should be considered in filtration legislation. Sodium, however, is difficult to categorize as a contaminant candidate. Sodium is potentially unhealthy: high sodium intake may cause hypertension. However, sodium levels in drinking water are typically low and unlikely to seriously harm one’s health. Sodium’s relative harmlessness makes it difficult to gauge how much sodium legislation should allow.
People are confused about how much sodium is healthy to drink. Researchers already know a lot about sodium, and compared to other contaminants, it’s not very dangerous. Because of this, the EPA wasn’t even sure whether they should list sodium on the CCL. However, they ultimately decided to include sodium, as they wanted to reexamine the current sodium levels in water that legislation allows. The EPA classified the relationship between water and sodium as a research priority; further research will help them clarify their stance on water and sodium. After sodium’s health effects have been sufficiently researched, the EPA will decide if sodium should stay on the CCL for other reasons.
You shouldn’t worry too much about the sodium in your drinking water. The sodium levels in drinking water are so low that they probably won’t seriously harm your health. The Food and Drug Administration’s sodium labeling system categorizes the sodium in an average glass of water as “very in low sodium.” And although sodium should not be consumed in excess, it is still an essential nutrient.
You don’t need to switch to bottled water to ensure a healthy, low-sodium diet. People consume far more sodium by eating than they do by drinking tap water. If you want to reduce your risk of sodium’s negative health effects, plan a healthy diet for yourself with a doctor or dietitian. To reduce sodium consumption, monitor your food, not your water.
Posted in HealthComments Off
Posted on 18 May 2011.
In July of 2010, the United Nations declared access to safe drinking water a human right. This resolution follows years of global campaigning to bring recognition to the problems of safe water and sanitation access. About 884 million people cannot access safe drinking water, and more than 2.6 billion people cannot access basic sanitation. More than two million people die annually due to a lack of clean drinking water and diseases caused by contaminated water. Diarrhea caused by drinking infected water is the second largest cause of the death of children under five years old.
Improvements in water and sanitation systems in developing areas of the world are directly linked to improvements in overall quality of life. Implementation of closed sanitary systems decreases child mortality by one-third. Access to clean water increases human productivity and overall health. Also, since access to water is often subject to discriminatory practices based on class, race, or gender, wider access to water can aid social equality in developing regions.
Both the World Health Organization (WHO) and the United Nations (UN) have begun programs to improve global access to drinking water and sanitation. The UN has declared the time period between 2005 and 2015 an International “Water For Life” Decade, during which massive educational and developmental programs have been implemented to increase the world’s access to water and sanitation. The WHO also has several programs in place that intervene in areas where water access is at risk; these programs educate people about water management and sanitation.
Education is vital to the drive for water and sanitation access. Undereducated populations need to understand the risks of using contaminated water. Local and governmental authorities need to learn the costs and advantages of developing new water distribution programs. People need to learn techniques for harvesting rainwater, creating wells, and treating, storing, and distributing water. Programs that help to build and install these systems are also very helpful.
The discrepancy between clean water access in the industrial world and in the developing world is alarming. Although this discrepancy has tapered in recent years, the problem of water access continues to plague much of the world’s population. People in privileged parts of the world continuously need to assist the less fortunate in their struggle for health and dignity. People who wish to help the UN and WHO to meet their goals can visit their websites for more information on how to donate time and money to their cause.
Posted in World ConservationComments Off