How Does Asbestos Cause Pleural Mesothelioma?

In cases of pleural mesothelioma, asbestos exposure occurs via inhalation of asbestos fibers. Once these fibers have entered the lungs, they work their way to the pleural membrane, and the body experiences great difficulty in expelling the fibers. Over a long period of time - typically two decades or more - asbestos fibers cause changes in these pleural cells, which may cause scarring of the lungs and, eventually, the formation of tumors.

When pleural cells become cancerous, they are no longer regulated by the mechanisms that control division of normal healthy cells. They begin to divide continuously, and this causes thickening of pleural membranes. As a result, lung capacity is reduced, and fluid begins to build up between pleural layers.

What is Pleural mesothelioma?

Pleural mesothelioma is the most common type of mesothelioma, a rare cancer that develops in the mesothelial cells that make up the mesothelium, a membrane that lines many of the body’s organs and cavities. In the case of pleural mesothelioma, the cancer develops in the lining of the lungs, called the pleura or pleural membrane.

he pleura is comprised of two layers which provide support and protection for the lungs and chest cavity. The outer layer, or the parietal layer, lines the entire chest cavity and the diaphragm. The inner layer, or visceral layer, covers the lungs. Pleural mesothelioma typically develops in one layer, but can metastasize, or spread, to the other layer.

Like all mesothelioma cancers, pleural mesothelioma is caused by asbestos exposure and develops when the toxic asbestos fibers become trapped in the spaces between the mesothelial cells.

Health Effects of Global Warming Hardest on Poor Nations

According to the scientists, who have mapped the growing health impacts of global warming, the data show that global warming affects different regions in very different ways. Global warming is particularly hard on people in poor countries, which is ironic, because the places that have contributed the least to global warming are most vulnerable to the death and disease higher temperatures can bring.

"Those least able to cope and least responsible for the greenhouse gases that cause global warming are most affected," said lead author Jonathan Patz, a professor at UW-Madison's Gaylord Nelson Institute for Environmental Studies. "Herein lies an enormous global ethical challenge."

How Does Global Warming Affect Our Health?

We know that global warming affects the weather and the earth's natural resources, but how does global warming affect the health of people and animals around the world?

Global Warming Leads to 150,000 Deaths Every Year

Global warming is not only a threat to our future health, it already contributes to more than 150,000 deaths and 5 million illnesses annually, according to a team of health and climate scientists at the World Health Organization and the University of Wisconsin at Madison—and those numbers could double by 2030.

Research data published in the journal Nature show that global warming may affect human health in a surprising number of ways: speeding the spread of infectious diseases such as malaria and dengue fever; creating conditions that lead to potentially fatal malnutrition and diarrhea; and increasing the likelihood of heat waves and floods.

What are Greenhouse Gases?

Many greenhouse gases occur naturally, such as water vapor, carbon dioxide, methane, nitrous oxide, and ozone. Others such as hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF6) result exclusively from human industrial processes.

disease by global warming

Malaria in temperate regions

Few people are aware that it is less than forty years since the final eradication of malaria in Europe and the United States. Indeed, the disease was common in the period from the 16th to 18th centuries that climatologists term the Little Ice Age [33], and data from burial records around the Thames estuary reveal that mortality in "marsh parishes" of England was comparable to that in areas of transmission in sub-Saharan Africa today [40,41].

Until the mid-19th century, the northern limit of transmission was roughly defined by the present 15°C July isotherm. Denmark and parts of Sweden suffered devastating epidemics until the 1860s. Incidence diminished thereafter and the disease had essentially disappeared around the turn of the 20th Century. The same was true in Finland, except for a brief recrudescence in 1941, during the Russo-Finnish war. Figure 1 shows the distribution of malaria cases in Norway between 1860 and 1920. In England, there was a gradual decrease in transmission until the 1880s, after which it dropped precipitously and became relatively rare, except in a short period following World War I. In Germany, transmission also diminished rapidly. After World War I it was mainly confined to a few marshy localities [36].

Fast Greenhouse Gas Analyzer (CH4, CO2, H2O)

The Fast Greenhouse Gas Analyzer (FGGA) is the only instrument capable of both high accuracy and fast measurements of methane, carbon dioxide and water vapor.

The FGGA is designed to work in ambient air and to deliver accurate measurements over a wide range of concentrations at rapid response rates (sufficient for eddy correlation flux applications). In particular, the FGGA reports methane, carbon dioxide and water vapor concentrations ranging from typical ambient levels to (over) ten times ambient levels with the high accuracy and reliability that you expect from LGR instruments. Also, the FGGA is not adversely affected by other atmospheric gases (no cross interferences) or changes in ambient atmospheric pressure (no pressure broadening effects). If desired, the Analyzer may be operated on DC battery power with an appropriate AC/DC inverter.

The FGGA suits many applications including eddy correlation flux measurements using established micrometeorological techniques, chamber flux measurements, landfill monitoring, and leak detection from natural gas pipelines.

As described in the Theory Section, the measurement strategy is based on high-resolution direct-absorption spectroscopy. The instrument includes an internal computer that can store data practically indefinitely on its internal hard drive (for applications requiring unattended long-term operation), and send real-time data to a data logger through its analog and digital (RS232) outputs. In addition, an Ethernet connection allows remote access to data files stored on the instrument’s hard drive.

Global warming causes by greenhouse effect

Greenhouse gases in the atmosphere (see above) act like a mirror and reflect back to the Earth a part of the heat radiation, which would otherwise be lost to space. The higher the concentration of green house gases like carbon dioxide in the atmosphere, the more heat energy is being reflected back to the Earth. The emission of carbon dioxide into the environment mainly from burning of fossil fuels (oil, gas, petrol, kerosene, etc.) has been increased dramatically over the past 50 years, see graph below.

Cause for global warming: Carbon dioxide emissions in million tons per year over the last 200 years.

Global warming disease warning

The World Health Organisation (WHO) says global warming could lead to a major increase in insect-borne diseases in Britain and Europe.

It has called for urgent government action to prepare for the spread of diseases like malaria and encephalitis.

The average temperature in Europe has increased by 0.8C during the past century and the average global temperature could rise by another 3.5C by the year 2100, as heat is trapped in the atmosphere by a build-up of gases such as carbon dioxide.

This would be accompanied by changes in rainfall patterns, greater precipitation and humidity in the atmosphere, and many new areas of floodwater.

This in turn could lead to an increase in disease-carrying pests such as ticks, mosquitoes and rats, which live in warmer climates and whose breeding-grounds are often in damp areas.

Three countries in the European region covered by the WHO - Azerbaijan, Tajikistan and Turkey - are already danger zones for mosquito-borne malaria.

The WHO says the disease is likely to spread to further areas within eastern Europe, and from there, possibly, to western areas.

If northern Europe becomes warmer, ticks - which carry encephalitis and lyme disease - and sandflies - which carry visceral leishmaniasis - are likely to move in.

Early Warning Signs of Global Warming: Spreading Disease

Climate change affects the occurrence and spread of disease by impacting the population size and range of hosts and pathogens, the length of the transmission season, and the timing and intensity of outbreaks (McMichael, 1996; McMichael et al., 1996; Epstein et al., 1998; Epstein, 1999). In general, warmer temperatures and greater moisture will favor extensions of the geographical range and season for vector organisms such as insects, rodents, and snails. This in turn leads to an expansion of the zone of potential transmission for many vector-borne diseases, among them malaria, dengue fever, yellow fever, and some forms of viral encephalitis. Extreme weather events such as heavy rainfall or droughts often trigger disease outbreaks, especially in poorer regions where treatment and prevention measures may be inadequate.

Mosquitoes in particular are highly sensitive to temperature. The mosquitoes that can carry malaria (Anopheline spp.) generally do not develop or breed below about 16° C, and the variety that transmits dengue fever (Aedes aegypti) is limited by winter temperatures below 10° C. Mosquito survival also drops at their upper temperature threshold, about 40° C. With sufficient moisture, warmer temperatures will generally cause an increase in mosquito abundance, biting rates, and activity level, and will accelerate the incubation of the parasites and viruses within them.

Warmer global temperatures will allow an expansion of the geographic range within which both the mosquito and parasite could survive with sufficient abundance for sustained transmission. Model predictions indicate that a 3° C global temperature rise by 2100 could increase the number of annual malaria cases by 50-80 million (not considering factors such as local control measures or health services) (Martens et al., 1995). The largest changes will occur in areas adjacent to current risk areas, at both higher altitudes and latitudes. In these regions, a temperature increase can convert areas that are malaria-free into areas that experience seasonal epidemics. In many cases, the affected populations will have little or no immunity, so that epidemics could be characterized by high levels of sickness and death.

Recent disease outbreaks are consistent with model projections that warmer, wetter conditions will lead to greater transmission potential at higher altitudes and elevations. Mosquito-borne diseases are now reported at higher elevations than in the past at sites in Asia, Central Africa, and Latin America (Epstein et al., 1998). This is coincident with growing evidence for significant warming at high altitude sites in tropical latitudes, as indicated for example by retreating glaciers (e.g., Fitzharris, 1996) and a 150 meter upward shift in the elevation of the freezing level (0° C isotherm) (Diaz and Graham, 1996). In New York City, an encephalitis outbreak in summer 1999 claimed three lives and prompted widespread pesticide spraying. The Centers for Disease Control have identified the West Nile virus as being responsible for this outbreak, a virus transmitted by mosquitoes that feed on infected birds (CDC, 1999a). The disease, which had not been previously documented in the Western Hemisphere, occurs primarily in the late summer or early fall in temperate regions, but can occur year round in milder climates (CDC, 1999b).

Diseases carried by rodents and other mammals may also be impacted by climate change. A recent study found a 60% rise in human plague cases in New Mexico following wetter than average winter-spring time periods (October-May) (Parmenter et al., 1999). Plague has only been in New Mexico since the 1940s, but a large increase in per capita cases occurred in the 1970s and 1980s associated with the wetter than normal conditions. The increased precipitation apparently enhances food resources for small mammals that serve as hosts for the infected fleas. The moister climate may also promote flea survival and reproduction. The study notes that if future climate conditions become more favorable for reproduction and survival of either wild mammal populations or their flea populations, then the probability of human infection via animal-flea-human contacts will likely increase.

The origins of the global warming scare

The global warming issue is political. It induced the ‘Earth Summit’ that was attended by several Heads of State in Rio de Janeiro during June 1992 and is the reason for the Kyoto Summit in Japan in December 1997. Governments have a variety of motives for interest in global warming. Each government has its own special interests in global warming but, in all cases, the motives relate to economic policies. In general, the USA fears loss of economic power to other nations while this is desired by those other nations. Universal adoption of ‘carbon taxes’, or other universal proportionate reductions in industrial activity, would provide relative benefit to the other nations. Unfortunately, if a few nations adopted the changes they would increase their manufacturing, transportation and energy costs and thus lose economic competitiveness and industrial activity to all other nations. Developing nations cannot afford technological and economic advances that would benefit them and also reduce their increases to CO2 emissions as they develop, so they are seeking gifted technology transfers and economic aid from developed countries.

The press are interested in selling papers and the TV companies want to gain viewers. Threat of world-wide disaster makes a good story, and the statements and actions of politicians together with great increase in scientific publications gave global warming an apparent authority. The media began to proclaim the worst imagined horrors. For example, massive floods were predicted due to melting of polar ice. and one UK TV programme went so far as to assert that the polar bears would die out because their habitat would melt. The public rely on the media to provide them with their information, so they came to believe the global warming scare because they were only given one side of the story. Politicians respond to public concern, so the politicians actions began to gain popular support.

On face value global warming is an environmental issue. Many environmentalists joined the bandwagon. Governments were offering money and the public were concerned at global warming. Any environmental issue which could be linked to global warming was said to be involved in the matter. But the environmentalist interest was aroused by the impact of the issue. Contrary to common belief, environmentalists did not raise awareness of global warming, they responded to it. Simply, environmentalist organisations were part of the general public and decided to use the issue when it became useful to them.

History of the greenhouse effect and global warming

Svante Arrhenius (1859-1927) was a Swedish scientist that was the first to claim in 1896 that fossil fuel combustion may eventually result in enhanced global warming. He proposed a relation between atmospheric carbon dioxide concentrations and temperature. He found that the average surface temperature of the earth is about 15^oC because of the infrared absorption capacity of water vapor and carbon dioxide. This is called the natural greenhouse effect. Arrhenius suggested a doubling of the CO₂ concentration would lead to a 5^oC temperature rise. He and Thomas Chamberlin calculated that human activities could warm the earth by adding carbon dioxide to the atmosphere. This research was a by-product of research of whether carbon dioxide would explain the causes of the great Ice Ages. This was not actually verified until 1987.

After the discoveries of Arrhenius and Chamberlin the topic was forgotten for a very long time. At that time it was thought than human influences were insignificant compared to natural forces, such as solar activity and ocean circulation. It was also believed that the oceans were such great carbon sinks that they would automatically cancel out our pollution. Water vapor was seen as a much more influential greenhouse gas.

causes of global warming

The Most Significant Cause

The buildup of carbon dioxide in the atmosphere, mainly from your fossil fuel emissions, is the most significant human cause of global warming. Carbon dioxide is released every you burn something, be it a car, airplane or coal plant. This means you must burn less fossil fuel if you want the Earth's climate to remain stable! And unfortunately, we are currently destroying some of the best known mechanisms for storing that carbon-- plants.

Deforestation increases the severity of global warming as well. Carbon dioxide is released from the human conversion of forests and grasslands into farmland and cities. All living plants store carbon. When those plants die and decay, carbon dioxide is released back into the atmosphere. As forests and grasslands are cleared for your use, enormous amounts of stored carbon enter the atmosphere.

An unstoppable feedback loop may happen if you let this continue. If the activities mentioned above warm the Earth just enough, it could cause natural carbon sinks to fail. A "carbon sink" is a natural system that stores carbon over thousands of years. Such sinks include peat bogs and the arctic tundra. But if these sinks destabilize, that carbon will be released, possibly causing an unstoppable and catastrophic warming of the Earth.

The oceans are no longer able to store carbon as they have in the past. The ocean is a huge carbon sink, holding about 50 times as much carbon as the atmosphere.[1] But now scientists are realizing that the increased thermal stratification of the oceans has caused substantial reductions in levels of phytoplankton, which store CO2.[2] Increased atmospheric carbon is also causing an acidification of the ocean, since carbon dioxide forms carbonic acid when it reacts with water. The tiny plants of the ocean, the very bottom of that vast watery food chain, are suffering from the effects of global warming, which means they are becoming less able to store carbon, further contributing to climate change.[3] As carbon sinks fail, the amount of carbon in the atmosphere climbs![4]

Methane's Huge Impact

Per unit of volume, it is twenty times more potent than carbon dioxide when its impact is measured over the course of a century. When you consider its effects within a single decade, methane is 100 times as powerful as carbon dioxide as a greenhouse gas![5] Carbon levels in the atmosphere are about 385 parts per million (ppm) currently, whereas methane is only about 1.8 ppm. But because methane is so powerful, it has the potential to have significant impacts on the future of global warming.

Methane is created when bacteria break down organic matter under oxygen-starved conditions. This occurs when organic matter is trapped underwater, as in rice paddies. It also takes place in the intestines of herbivorous animals, such as cows, sheep, and goats. Because human agriculture has grown over time to engulf most of the arable land on the planet, it is now adding a lot of methane to the atmosphere. Landfills and leakage from natural gas fields (methane is a component of natural gas) are also significant sources of methane

Clathrates are a hidden source of Methane. Clathrates are frozen chunks of ice and methane that rest at the bottom of the world's oceans. As the water warms, the ice melts, and the methane is released. If the current global warming, which is caused by humans, were to cause changes in the Earth's ocean currents, then a rapid melting of clathrates would be possible. This too would create a positive feedback loop that would cause further global warming. It is believed that some of the warming cycles in the Earth's history have been caused by the sudden thawing of clathrates.[6]

A Growing Problem

The "green revolution" of the twentieth century has allowed the farmers of the world to use chemical fertilizers and machines to produce far more food than they ever did before. One of the primary components of the green revolution has been the development of nitrogen fertilizers that dramatically accelerate the growth and productivity of plants in the field. Plants "fix," or capture, nitrogen on their own as well, but green revolution technologies have become so popular that humans are now adding more nitrogen to the earth than all of the plants in the world combined![7

Nitrogen oxides have 300 times more heat-trapping capacity per unit of volume than does carbon dioxide, and we release them every time we apply fertilizer to soil. A recent United Nations Food and Agriculture Organization study found that modern farming is contributing more to global warming than all of the transportation sector combined![8] This is due partly to the fuel burned in modern farming, but more significantly, to the release of methane and nitrogen oxides.

What is - Global Warming?

Global Warming is defined as the increase of the average temperature on Earth. As the Earth is getting hotter, disasters like hurricanes, droughts and floods are getting more frequent.

Over the last 100 years, the average temperature of the air near the Earth´s surface has risen a little less than 1° Celsius (0.74 ± 0.18°C, or 1.3 ± 0.32° Fahrenheit). Does not seem all that much? It is responsible for the conspicuous increase in storms, floods and raging forest fires we have seen in the last ten years, though, say scientists.

Their data show that an increase of one degree Celsius makes the Earth warmer now than it has been for at least a thousand years. Out of the 20 warmest years on record, 19 have occurred since 1980. The three hottest years ever observed have all occurred in the last eight years, even.

Earth should be in cool-down-period

But it is not only about how much the Earth is warming, it is also about how fast it is warming. There have always been natural climate changes – Ice Ages and the warm intermediate times between them – but those evolved over periods of 50,000 to 100,000 years.

A temperature rise as fast as the one we have seen over the last 30 years has never happened before, as far as scientists can ascertain. Moreover, normally the Earth should now be in a cool-down-period, according to natural effects like solar cycles and volcano activity, not in a heating-up phase.