Environtmental and Global Health

How much Arctic warming affect the vegetation?

mzPOTTER — Mon, 30 Apr 2012 00:00:59 +0000

It is likely to produce changes in vegetation cover in the Arctic, which would have far-reaching implications.

1. The Arctic has three main vegetation types: polar deserts in the north, the boreal forests in the south and tundra in the middle. Is expected to increase in temperature favors the northward expansion of boreal forests, which travel to the Arctic tundra, and a preview of the tundra into the polar deserts.

2. The planned expansion of the forest will intensify global warming, as new woodlands will be darker and absorb more solar energy than the existing tundra. However, this effect could be partially offset by increased absorption of carbon from the atmosphere of the forest.

3. The warming will affect insect pests increasingly large areas of forest. Most scenarios project an increase in forest fires in all ecosystems.

4. It is expected that climate change do to thrive in the Arctic a greater variety of crops and the growing season will be longer. However, it is likely to increase the problems caused by insects, crop diseases and the spread of weeds.

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How will Arctic warming the rest of the planet?

mzPOTTER — Sat, 28 Apr 2012 00:00:47 +0000

Arctic warming and its consequences have worldwide impact.

1. The amount of solar energy reflected back to space decreases with the thaw, which accentuates the warming of the surface.

2. The Arctic melt and increased rainfall in the region could provide fresh water to the oceans. This could affect ocean currents in the North Atlantic.

3. As warming progresses, the thawing of permafrost could release into the atmosphere as much greenhouse gases. Furthermore, the heating can stimulate biological growth, and therefore the absorption of CO2. The melting of glaciers can contribute to an increase in sea level.

4. From 2100, the glaciers will cause alone an increase in sea level of about 5 cm (total is expected to increase between 10 and 90 cm this century).

5. It is likely that access to resources held by the Arctic be altered by climate change. These resources are part of wildlife, including whales, seals, birds and fish that are sold worldwide, and oil reserves, natural gas and minerals.

Changes in Arctic ecosystems affect everyone. Migratory species will be particularly concerned to see altered their breeding grounds and food sources.

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Global Warming and The Arctic Region

mzPOTTER — Tue, 24 Apr 2012 00:00:03 +0000

The Earth’s climate is changing. During the last two centuries, the Earth’s surface temperature has increased an average of 0.6 °C. The observed warming over the last 50 years is attributed largely to human activity and, in particular the burning of fossil fuels.

Information on past climate conditions, obtained from ice cores and other methods indicate that the current increase in temperature around the world due to natural climate variability. The rise in temperature in the Arctic has occurred at a rate twice that of the rest of the world, and climate change is felt with particular intensity. Changes in arctic climate will also affect the rest of the world by causing an increase in global warming and sea level.

The Arctic region is the area surrounding the North Pole. It is, roughly, an ocean surrounded by land. The northern end is mostly covered with snow and ice, while the boreal forest covers the southernmost part of the Arctic. Between these extremes are vast expanses of tundra. The Arctic has a set of plants, animals and people who survive in conditions that are among the most extreme of the planet and have remarkably adapted to these conditions. Climate change, pollution and increased exploitation of resources contribute to increasing pressure on populations and ecosystems in the Arctic.

The Arctic is home to a population of about four million people, which includes an increasingly large majority of non-indigenous settlers. The Arctic region includes Greenland, Iceland and the northern parts of Norway, Sweden, Finland, Canada, Russia and the U.S. From the economic point of view, the region depends heavily on natural resources, ranging from oil fields, natural gas and metals to fish, reindeer and birds. In recent times has also developed the tourism sector in many parts of the Arctic.

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WHO and IARC Recommendations about Arsenic

mzPOTTER — Sat, 21 Apr 2012 00:00:55 +0000

What happened in areas where drinking water is heavily polluted?

Drinking water from contaminated sources normally contains only small amounts of arsenic. Drinking water from underground wells may be heavily contaminated in some areas where the groundwater is in contact with the arsenic occurs naturally in minerals. This can become a serious problem in countries like Bangladesh, West Bengal in India and Taiwan. In Bangladesh, many people regularly drink whose drinking water arsenic concentrations are 5 to 100 times higher than normal. People living in these regions have suffered adverse health effects, some examples are skin cancer and skin changes.

What are recommendations WHO and IARC about arsenic?

Other international bodies have previously evaluated arsenic. Thus, the World Health Organization (WHO) established a guideline value of 10 mg/liter for arsenic in drinking water. According to the International Agency for Research on Cancer (IARC), there is sufficient evidence to conclude that “arsenic and arsenic compounds” cause cancer in humans.

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What are the effects of arsenic on human health?

mzPOTTER — Tue, 17 Apr 2012 00:00:22 +0000

If a human being ingested a large amount of arsenic, in a form easily absorbed, may cause a rapid poisoning and death. The intestine, heart and nervous system are affected. Those who survive a severe poisoning may develop pigment spots on the skin and damage to red blood cells, bone marrow (where blood cells are produced), liver, nerves and brain.

A long-term exposure to high levels of arsenic in drinking water can cause a thickening of the skin or the appearance of dark spots on the skin and skin cancer, lung, bladder or kidney. Exposure in the workplace, particularly through inhalation of air can cause lung cancer. Smoking increases the risk of this cancer.

In Taiwan, the intake of long-term arsenic mainly through drinking water from contaminated wells, causes a disease called “black foot disease” (“Blackfoot disease” in English). The blood vessels of the leg and foot are damaged. This causes a cooling of the foot, a loss of feeling and eventually gangrene.

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Effects of Arsenic in The Environment

mzPOTTER — Sat, 14 Apr 2012 00:00:31 +0000

What are the effects of arsenic on laboratory animals?

Arsenic can have negative effects on laboratory animals but some forms of arsenic are more toxic than others. When exposure is high enough to cause poisoning or cancer, death may be one consequence. Many body parts may be damaged due to contact with arsenic: skin, intestines, lungs, heart, blood vessels, immune system, urinary system, reproductive organs and nervous system, among others. Arsenic can also damage the chromosomes, which contain genetic material within cells of the body.

What are the effects of arsenic in the environment?

Living organisms, both terrestrial and aquatic react differently to exposure to arsenic. The effects depend on the chemical form of arsenic, the type of surrounding environment and the biological sensitivity of each species. Individual organisms or whole populations may be affected. Among the negative effects are death, inhibition of growth and reproduction. When arsenic contaminated natural surroundings, the number of species found is reduced.

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What happens to arsenic in the body?

mzPOTTER — Tue, 10 Apr 2012 00:00:58 +0000

When inhaled because arsenic is present in air particles, the amount absorbed by the blood system depends on two factors: the solubility of the variant of arsenic and how small particles containing it. That said, most of the arsenic in the body comes from food. In the intestine, soluble arsenic compounds in foods are quickly absorbed into the bloodstream. Many arsenic compounds are rapidly transformed by the body and eliminated through the urine. However, the ability of people is different at the time of removing arsenic compounds.

The amount of arsenic in the body can be determined by taking blood samples, urine, hair, nails and measuring the level of arsenic or arsenic containing substances. This is rapidly cleared from the blood, so blood levels only indicate recent high exposures, such as poisoning or long-term exposures if they are repeatedly and are of great intensity. Urine levels are best determined by a recent exposure, while levels in hair and nails may indicate past exposure.

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Arsenic in Environment | Level of Exposure

mzPOTTER — Sat, 07 Apr 2012 00:00:42 +0000

What are the levels of arsenic exposure?

The levels of arsenic in the environment are variables. In air, levels are lowest in remote or rural areas, higher in urban areas and higher in areas close to industrial sources. In water, arsenic levels are lower in seawater, higher in the rivers and lakes and the highest groundwater in areas with volcanic rock deposits of minerals rich in arsenic. Background levels of arsenic in soil and sediment increase when there are sources of pollution, whether they are natural.

The amounts of arsenic in live animals, plants and microbes vary. The amounts depend on the level of local pollution and the type of organism as some tend to accumulate arsenic in their bodies. Arsenic is generally present in animals living in the sea where they live in freshwater or in plants and other terrestrial animals. Terrestrial plants may accumulate arsenic compounds absorbing soil or if the air deposited on the leaves.

The major sources of arsenic exposure in humans are food and water. Foods are generally the major source, except in the areas where the drinking water is contaminated with arsenic naturally. The amounts of arsenic inhaled by non smokers are very small, except in areas polluted by industries. Smokers inhale more arsenic because this is one of the hundreds of chemicals in the smoke of snuff. Exposure to arsenic in the workplace can be quite high, but in many countries the amounts present in the workplace air are controlled.

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Arsenic in Environment

mzPOTTER — Tue, 03 Apr 2012 00:00:25 +0000

The arsenic is a natural element that behaves like a metal. It is present in the environment naturally and as a result of certain human activities. It comes in different ways. There is both under inorganic and organic form. Generally considered that inorganic arsenic is more toxic.

The level of arsenic can be measured by different laboratory methods. Some may differentiate different types of arsenic and other possible to measure accurately very small amounts of arsenic.

Where does arsenic in the environment?

In the natural environment, arsenic is present in fairly abundant in the earth’s crust and in smaller amounts in rock, soil, water and air. It is present in many minerals. About a third of the arsenic in the atmosphere comes from natural sources, such as volcanoes, and the rest comes from human activities. When natural geological contamination, can be found high levels of arsenic in drinking water that comes from deep wells. This is the case of Bangladesh.

Some industrial processes such as mining, metal smelting or coal-fired power plants contribute to have arsenic in air, water and soil. The use of arsenic in some agricultural pesticides and certain chemicals used to preserve wood, also results in environmental pollution.

The arsenic comes in different forms and of the arsenic is transported from one medium to another in the environment, which can cause a change in form. Wind or water can move the arsenic in the rocks or eroded soils. Many organic compounds are fixed on the ground and only move a little when water seeps through the soil. When industrial processes or volcanic activities emit arsenic to the atmosphere, arsenic binds to the wind carries particles and fall back to the ground. Microbes in soils and sediments also emit substances into the atmosphere that contain arsenic. These are transformed later into other compounds of arsenic again fixed on the floor.

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What can be achieved with solar energy?

mzPOTTER — Sat, 31 Mar 2012 00:00:16 +0000

By collecting solar radiation properly, we could get heat and electricity.

The heat is achieved through the use of solar thermal collectors, and electricity through the photovoltaic modules. Both processes have nothing to do with each other, nor as to its technology or its implementation.

Let’s talk first heat utilization systems. The heat collected in the sensors can be used to meet many needs. For example, you can get hot water for domestic or industrial consumption, or for heat our homes, hotels, schools, factories, etc.. We can even allow pools and air condition the bathroom for most of the year.

Also, although it may seem strange, one of the most promising applications of solar heat is cooling during the warm season, precisely when there is sunlight. Indeed, for cold is necessary to have a “hot source”, which may well be caused by solar collectors installed on the roof or roof. In Arab countries are fully operational and many air conditioners that use solar energy effectively.

Agricultural applications are vast. Solar greenhouses are available with greater and earlier crops, agricultural dryers use less energy when combined with a solar system, and, to cite another example, can run desalination plants or water purification without consuming any fuel.

The “solar cells” photovoltaic solar panels arranged, and produced electricity in the first space satellites. Currently emerging as the ultimate solution to the problem of rural electrification, with a clear advantage over other alternatives, because, having no moving parts panels, totally impervious to the passage of time, do not pollute or produce no noise at all, do not consume fuel and maintenance free. In addition, even with less performance, also work on cloudy days, since that capture the light that filters through the clouds.

The electricity thus obtained can be used directly (for example to draw water from a well or water by an electric motor), or be stored in batteries for use in the night hours. Photovoltaic electricity generated can also be injected into the grid, getting a good value for money, as more and more countries prevail both small and large producers of photovoltaic electricity, given the benefits it brings to the environment.

If you get the price of solar modules fall further loss, potenciándose large-scale manufacture, it is likely that for the third decade of the century, much of the electricity consumed in sun-rich countries has its origin in the photovoltaic conversion.

Solar energy can be perfectly complemented with other conventional energy sources, to avoid the need for large and expensive storage systems. Thus, a well insulated building can have hot water and solar heating, with the support of a conventional gas or electric work only during periods without sun. The cost of conventional energy would be only a fraction of that achieved without the existence of the solar system.

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