Parasites: Malaria

Malaria is a disease caused by parasites which is still unfortunately common in the world. Although many people mistakenly believe malaria is the result of the virus or infection caused by bacteria it is actually attributable  to a parasitic organism known as plasmodium falciparum. The life cycle of this organism is represented below.

Malaria is most present in the southern hemisphere especially in Africa. This is true for several reason. For one, the climate in the region is ideal for mosquitoes which serve as a vector which carry the parasite to humans. Another condition that makes Africa, especially sub-Saharan Africa, especially vulnerable is the poor infrastructure and high rates of poverty which characterize the region. There have been major global health initiatives to halt the spread of malaria in Africa including projects which distribute netting. The map below shows the prevalence of malaria throughout the world.

 

Malaria is one of the most serious health problems that affect the developing world. This parasitic organism places a high burden of disease on a region of the world which already struggles economically, politically, and in terms of health.

Toxic Metals: Mercury

Mercury, or "quicksilver", is one example of a toxic metal. Its atomic number is 80 and its symbol is Hg. Mercury has several qualities which make it unique. For instance, it is the only metal that is liquid at standard atmospheric conditions, aka room temperature. However, like many other metals mercury is toxic to humans.

There are both natural and man made sources of mercury emissions. In nature, volcanoes release mercury into the atmosphere when they erupt. Mercury is also released by human industries, specifically through combustion based power plants. Historically, coal-fired power plants have been a major culprit due to the fact that atmospheric mercury is a bi product of the coal burning process. However, new technology together with stricter regulations have significantly reduced mercury output by American power plants. The US Clean Air Act listed mercury as one of the toxic substances that would be monitored and limited. Plant Scherer in Macon, which provides power to most of the middle Georgia area, has in recent years reduced its mercury output to almost zero. 

Another major environmental threat posed by mercury is its tendency to bio-accumulate in fish. Fish absorb the toxic metal when it is introduced into their environment and it accumulates in their tissues.  This can cause health problem in humans who eat the fish. Public health officials advise limiting consumption of certain fish that are known to accumulate large amounts of mercury as is evidenced by the chart below.

Because mercury poisoning is a painful and scary threat, communities often react with fear when cases are reported. The media also feeds into this by frequently airing stories about local detection of mercury in fish. Below is an example of one such news cast.

The presence of mercury in our environment is important to monitor because of its impact on human health. However, history has taught us that as we learn more about its dangers, technology responds. As is demonstrated by the introduction of products such as non-mercury thermometers and emission "scrubbers" for power plants. 

Community Gardening

Community gardens are common plots of land that people can come together and use as a place to grow vegetables or flowers. The history of gardening in the United States is long and has gone through many changes of the years. For example, during WWII people were encouraged to plant "victory gardens" which were vegetable gardens that could help families sustain themselves without detracting from resources that could be devoted to the war effort. Today people grow gardens for many different reasons. Community gardens, just like private gardens, can serve many different purposes. The video below outlines several different types of community gardens.

In some places community gardens can be used to beautify the area. Other community gardens might serve as a way to bring people together. One intriguing modern use for community gardens is to provide nutritious foods in neighborhoods that might not otherwise have access to them. There are areas in the United States known as food deserts where people simply do not have access to fresh healthy food. Most of these areas are severely impoverished. Community gardens provide an alternative solution that offers nutritious foods and a chance to involve and strengthen the community.

Macon is one city which has begun to explore the possibilities of community gardens. For those who are interested in learning more, there is a community garden right next to Mercer's campus at the Methodist on Montpelier. 

Rachel Carson

Rachel Carson is a notable environmentalist and author. She was born in Springdale, Pennsylvania on May 27, 2907. Through her education at Chatham University and John Hopkins University, Carson gained a background in both English and biology. This unique skill set allowed her to become one of the most influential voices in environmental consciousness in the 1960's. Her most famous contribution to the field was her 1962 book Silent Spring. This shocking tale of the dangers of many common pesticides, such as DDT, brought to light very important environmental health concerns.

Before the publication of Silent Spring, DDT and other harsh chemical pesticides were in common usage in the agricultural sector of the United States. Carson's book opened the dialogue about the harmful effects of such pesticides on human health. Although there has been controversy, both in her lifetime and after her death in 1964, over the effect her book had on the pesticide industry and the agricultural impact of banning highly effective pesticides, most people now agree that Carson's contribution to environmental health was substantial and much needed. Although she died only two years after the publication of her book, her legacy lives on in the new breed of environmentalists who even today strive to make sure that human health is not sacrificed in the name of output or productivity.

Global Warming

The concept of greenhouse gasses leading to man-made global warming has existed in the consciousness of some for many years, and the debate grew in intensity and evidence in the 1990s. In the United States, public awareness of global warming reached its peak in 2006 with the release of the controversial documentary An Inconvenient Truth, which chronicles former Vice President Al Gore's crusade to educate the public about the dangers and man-made nature of the climate change we are experiencing.

While the initial debate focused on whether or not the world was experiencing a significant warming, today it has more to do with whether or not it is attributable to human interference. Estimates put the rise in the global surface temperature at 0.6 degrees Celsius, plus or minus 0.2 degrees. While this does not seem like much, the following infographic depicts how much damage even a small amount of warming can cause:

While most people will at this point agree that the earth is in fact experiencing a significant period of warming, many attribute this warming to the natural cycle of warming and cooler that the earth experiences over time. The majority of the scientific community, however, believes that this change can be attributed to the effect of greenhouse gasses in the atmosphere, which hold heat in. These experts make their case by graphing the increase in carbon dioxide (a greenhouse gas) emissions against warming trends. The result looks something like this:

While the media presents the issue as an extremely contentious one, the scientific community, with a few notable exceptions (hi Dr. Rood!), seem to believe that at least some of the warming we have experienced can be attributed to human factors. The following graphic displays the results of several different studies about opinions of global warming in the scientific community:

Ultimately, it is difficult to know exactly how much of the warming we are experiencing is attributable to human factors, and how much is part of a natural temperature cycle. However, we can all agree that whether or not humans contributed to the causes of warming, humans will suffer the consequences. It is important that rather than investing our time in ad hominem attacks against those who believe differently than us, we focus on preparing our world, especially in the underdeveloped regions that are likely to experience the brunt of climate change's most negative effects, for the changes that are occurring.

Finally, because this is a contentious issue which often makes people uncomfortable or angry, I leave you on a lighter note. Here is the definitive proof of global warming!

Banqiao Dam Disaster

On August 8, 1975 the Banqiao Reservoir Dam in Zhumadian Prefecture, Henan Province, China, suffered a catastrophic failure, leading directly to the deaths of 26,000 people and affecting more than 11 million people in total. Although some may consider a dam failure to be an engineering failure or man-made disaster, the Banqiao Dam incident is officially considered a natural disaster because of the extreme rainfall and flooding that precipitated the disaster. A typhoon caused more than a whole year's worth of rain to fall in 24 hours. While the dam was engineered to withstand above average rainfall, it did not have the capacity to handle this extreme flooding, which climate experts have labeled a "once-in-a-thousand-years" event. The water peaked at 117.94 meters above sea level, which was 0.3 meters higher than the wave protection wall. The resulting dam breakage released over 701 million cubic meters of water in six hours.

Several measures were unsuccessfully taken to avoid the breakage of the dam in the first place. Workers at Banqiao requested permission to open the dam and thus avoid catastrophic failure, however, the response authorizing them to do so, sent by telegram, failed to reach its recipients. Communications orders also failed in the transmission of evacuation orders, and seven county seats were flooded before they had been fully evacuated, leading to a high death toll. At the time, there was no cohesive early warning system in China for disasters of this kind, which could have prevented much of the damage.

The first response to the disaster was the intentional destruction of several other dams in the area in order to avoid a chain reaction of similar dam breaks. Next, the People's Liberation Army was deployed to for initial disaster aid. Their primary job was to rescue victims who had survived the initial massive release of water and were now trapped by debris, stranded in a dangerous environment, or separated from their homes and families. Next, the government began airdropping supplies of food and medicine to the worst-affected areas. The long-term consequences of this disaster and the reactions to these consequences were largely concerned with famine and epidemics due to destroyed or damaged agricultural land and the spread of water-borne illnesses. All told, it is difficult to say exactly what the death toll, environmental health impact, and economic damage caused by this disaster was. It is also difficult to say how an early warning system and more advanced and organized approach to disaster relief could have mitigated these impacts. However, this scenario does illustrate the dangers that natural disasters can pose to environmental health, especially when disaster preparedness is not functioning at the highest possible level.

Water Shortages in Gaza

I am very interested in the shortages of clean water in the Palestinian Territories, particularly in the Gaza Strip. The area has a long history of conflict, and as such the health of the population is at significant risk. In terms of climate, the region is arid, with hot dry summers and frequent periods of drought. It shares borders with Israel and Egypt and backs up to the Eastern coast of the Mediterranean Sea. Due to the tensions between Israel and the Palestinian Territories and the power and influence which Israel holds, insufficient resources are devoted to providing clean water in Palestinian areas. In fact, Israeli settlers often contribute to the problem, polluting the few water sources that Palestinians have access to. Israel also draws water from the underground aquifers which extend into Palestinian territory. Because both Israel and Palestine are pressed for water due to their environmental conditions and heavy reliance on the limited water supply available in underground aquifers, access to water often causes or exacerbates conflict.