Sunday, July 17, 2011

Rachel Carson responsible for the death of millions of Africans

Rachel Carson wrote a book called "Silent Spring", this book contained misrepresentations about the pesticide DDT. The government bought into her claims of DDT and many people died due to it. DDT is used to fight malaria, and if exposed to DDT can have harmful effects. Research has found that DDT can cause a significant decrease in mental and physical functioning among young children and problems increase with more exposure (Swartz, 2007). The Environmental Protection Agency (EPA) states that DDT is a human carcinogen (Swartz, 2007).

This issue is huge and from my readings of Rachel Carson she was an important icon. In my opinion the government should have had a more intelligent response to the book that Rachel Carson wrote. You can't always believe what you read. Rachel Carson should have had a more direct approach to the information she wrote about and should have been more sincere.

Fair Fairness & Accuracy in Reporting (2007, September/October) RE: Rachel Carson, Mass Murderer? 
[Web log post]. Retrieved from http://www.fair.org/index.php?page=3186

Friday, July 8, 2011

Global Enviornmental Health: Mercury, Now a Toxic Element

Global Enviornmental Health: Mercury, Now a Toxic Element

Mercury, Now a Toxic Element


Adapted from periodictable.com

Mercury is known as a chemical element. Symbol is Hg and atomic number 80 in the periodic table. 

Mercury is also known as the quicksilver and/or hydrargyrum. The word hydrargyrum is from greek language "hydro", meaning water, and "argyrum" meaning silver. Mercury is the only known metal  in liquid form at room temperature and standard pressure.


65% of mercury released into the environment is from coal-fired power plants, 40% of mercury emissions were measured within the United States  in 1999.

3.0% of mercury emissions contaminates and settles in waterways.

Fish that live in contaminated water accumulate mercury and in the higherst concentration of mercury is then converted to methylmercury, and is the most toxic form of mercury. Mercury that is consumed can have both chronic and acute symptoms such as, depression, fatigue, irritability, loss of memory, and vivid dreams.

Methylmercury poisoning can occur through exposure to water contaminated by mercury, inhaling mercury vapor, and as already mentioned through eating fish contaminated with high levels of mercury.


Methylmercury is said to be fat soluable and forms mostly around the viseral and muscle tissue areas. When large fish such as, albacore tuna, king mackerek, shark, swordfish, and tilefish consume smaller fish, a process known as bioaccumulation occurs. The toxic methylmercuy found in the small fish has now become ten times as poisonous.


Although, low amounts of mercury can still be found among areas not under study, a process known as  biomagnification can result and have a  toxic effect on consumers at the top of the aquatic food chain.



Treatment of methylmercury poisoning is currently under research however, there are five different pharmocological treatments to aid in the secreation of mercury.


Currently, the World Health Organization, OSHA, NIOSH and the Environmental Protection Agency regualte any use of the toxic mercury, and mercury should only be handled with adequate protective suites.


USGS Science for a Changing Wrold (October, 2000). Mercury in the Environment. Retrieved from http://www.usgs.gov/themes/factsheet/146-00/

Wednesday, June 29, 2011

Most Imprortant Pathogens to Know About

Tapeworms are just one of a class of parasitic flatworms, of the phylum Platyhelminthes. Thousands of species of parasitic flatworms have been identified, and live in vertebras.
Kingdom: Animalia
Phylum: Platyhelminthes
Class: Cestoda
These are the subclass in order of association:
Tapeworms are hermaphrodites, they consist of both male and female reproduction system. The reproductive system has one or many testes, cirrus, vas deferens and seminal vesicle as male organs, and a single lobed or unlobed ovary with the connecting oviduct and uterus as female organs. Although, these parasites have both reproductive systems they have to reproduce with another, which is called cross-fertilization. The life cycle of a tapeworm is not asexual, an intermediate host and a definitive host is required, which demonstrate a two-phase life cycle.
Life Cycle of Tapeworm

Tapeworm
Tuberculosis (TB) is a common and fatal infectious disease. TB is contracted from the air of other individuals who have it and cough, sneeze, or spit saliva and found in the lungs.
Tuberculosis needs to be treated immediately, and if left untreated will destroy about 50% of people. Symptoms of Tuberculosis (TB) are chronic cough, blood-tinged sputum, fever, night sweats, and weight loss. Treatment is a long-term dosing of antibiotics.
Prevention of Tuberculosis has been regular screenings and vaccinations. Most cases of Tuberculosis are found in developing countries; 13.7 million active cases were found in 2007, 9.3 million new cases, and 1.8 million deaths. South Africa is known to have the highest prevalence rate of Tuberculosis.   

Infectious Diseases in 7 Continents

The World Health Organization (WHO) has reported the top eleven infectious diseases worldwide.  
1.       Lower Respiratory Infection
2.       HIV/AIDS
3.       Diarrheal Diseases
4.       Tuberculosis (TB)
5.       Malaria
6.       Measles
7.       Pertussis
8.       Tetanus
9.       Meningitis
10.   Syphilis
11.   Hepatitis B

Parasites in Seven Continents

North America-Giardia duodenalis is a common parasite found in North America and around the world. Giardia duodenalis is a flagellated protozoan parasite that reproduces in the small intestine of human, cats, dogs, and birds. The mammalian host are beavers, cows, deer, and sheep. Transmission of giardia duodenalis is through ingesting contaminated food, water, fecal oral route due to inadequate hygiene.

South America-Hookwarm is a common parasitic nematode found in South America. This parasitic nematode lives in the small intestines of the host, which are human, cats, and dogs. One can prevent contraction of this parasite by using only designated receptacle to defecate, wearing shoes, and maintaining pets by de-worming.


Asia- parasitic protists which cause Malaria in South Asia. There are over 200 known species of Plasmodium of these 200, 11 of these species are known to infect humans. Some of the other species affect monkeys, rodents, birds, and reptiles. 


Tapeworms are parasitic flatworms, and infect the digestive track. The larvae can be ingested through undercooked food. In humans, the most common type is pork tapeworm, the beef tapeworm, fish tapeworms, and the dwarf tapeworm.  Most occurrences happen were there is inadequate sanitation. Sheep and cattle can also get infected with the tapeworm.  Transmission of tapeworms is generally through ingested consumption of tapeworm eggs through food, water, or soil contaminated with human or animal (host) feces.


Trichinella spiralis is a nematode parasite found in bears, humans, pigs, and rats and causes the disease Trichinosis. Also known as the "pork worm" because it is commonly found in undercooked pork. After ingestion of the parasitic nematode, inflammations occur and symptoms of diarrhea, nausea, sweating and vomiting surface. If not treated quickly, within five to seven days, fecal edema and fever occur. After 10 day of non-treatment, the individual has problems breathing, intense muscular pain, slow pulse rate and decrease in blood pressure. Heart damage can occur as well as, various nervous disorders leading to death.  
Africa and Europe-Trypanosoma is a single celled parasite that cause sleeping sickness in Sarharan Africa. They are classified as Kinetoplastida and are transmitted via a vector. Trypanosoma infect a verity of host and cause a various disease, including the fatal sleeping sickness.




Wednesday, June 22, 2011

Yes, human activity causes global warming.

Global warming is casued by human activities specifically those increased greenhouse gases through deforestations and burning of fossil fuels. With the increase of global temperatures the sea level will rise, which will result in changing patterns of percipitation. These changes will bring severe weather occurences such as, heatwaves leading to drought, and heavy rainfall leading to flooding.


Naturally occuring greenhouse gases are composed of mainly water vapor, carbon dioxide (CO2), methan (CH4), and ozone. Since the begining of the industrial revolution scientist have study the naturally occuring greenhouse gases and the human activity which seem to increase and have a harmful effect on the globle.

The recent burning of fossil fuel alone have increased carbon dioxide levels by 75% in comparison to the levels in the past 20 years. The large shift in deforestation and land use has also contributed to this increase in emission of carbon dioxide.

During the 21st century, climate change is going to have a negative impact on millions of people due to coastal flooding, with a decreased agricultural food supply resulting in malnurtition and other health conditions. 

 
If this type of global warming continues through the 21st century the cost would out weight the benefits. Economic studies suggest a great loss in the worlds' Gross Demestic Product (GDP).