Rachel Carson responsible for the death of millions of defenseless Africans

Rachel Carson

Born: May 27, 1907
in Springdale, Pennsylvania

Died: April 14, 1964
in Silver Spring, Maryland

Who is she?

     Rachel Carson was a scientist, writer and ecologist from Pennsylvania. She loved nature and graduated from Pennsylvania College for Women  in 1929 with a degree in marine biology and from John Hopkins University in 1932 with a Masters in zoology. She worked at the U.S. Bureau of Fisheries as a writer and at the U. S. Fish and Wildlife Service as a scientist, editor, then editor in chief. She also regularly wrote pamphlets on conservation and natural resources. She received "heat" from several chemical agencies and members in government for pointing out the harmful effects of DDT and misusing pesticides therefore influencing the banning of DDT. She remained strong minded in her protests and testified before Congress in 1963 demanding new policies that protected human health and the environment. She died one year later after losing a battle to breast cancer.

How is she responsible for the death of millions?

     In her 1962 book Silent Springs she stretched the truth about the effects of DDT. In response to her claims and protests DDT was banned. She is responsible for the death of millions because DDT is used as a form of pest control for the Anopheles mosquito which spreads malaria.  Due to the banning DDT was no longer used and the mosquito was allowed to flourish further spreading the disease. Millions of  people mostly those in subtropical and tropical climates including Africa are affected from and even die from malaria. 

My impressions of her.

  It it disappointing that she presented misinformation in her book, but I get the impression that her intention was not to kill millions of people by influencing the banning of the pesticide used to control the mosquito population. By looking at her bibliography it appears as if her focus in life was to protect human life and conserve the environment for future generations. Even when she was battling breast cancer it appeared as if her goal was to make the world a better place through environmental awareness. Maybe she stretched the truth because she felt that she was fighting a losing battle both professionally and physically. Even if her intention was a positive one it was still wrong for her to do what she did. I do not hate her, but instead hope that updated scientifically sound information is used to develop more efficient environmental health practices and laws.

Mercury in the environment and its Human Health Risks

Link to brochure

What is Mercury and why should you be concerned?

Mercury is a chemical element on the periodic table with the symbol Hg. It is highly toxic in both its liquid and gaseous forms. If ingested or inhaled it can cause brain, liver, and central nervous system damage. It is bioacumulative and is easily absorbed through the skin. When exposed to high amounts over long periods of time death can occur. When working in a lab it should be used under a well- ventilated hood. In the natural environment Mercury ingestion can be minimized by eating aquatic foods lower on the food chain.

Global Cycle of Mercury

The global cycle of mercury includes a combination of anthropogenic sources (industrial combustion, mining) and natural sources (ocean soils) which introduces mercury into water sources. As mercury enters the aquatic environment it is consumed by small organisms which are consumed by more predatory species further concentrating the levels of mercury toxicity.

Conversion of Mercury into Methyl Mercury

Methyl mercury is mercury’s most toxic form. It affects the immune system, alters genetic systems and damages the nervous system. It is particularly toxic to developing embryos. Mercury becomes methyl mercury through oxidation of Hg (0) to Hg (II) and 2 transformations from Hg (II) to CH3HG+ (methylation)

Bioaccumulation and Biomagnification of Methyl Mercury in Aquatic Food Chains

Mercury biomagnifies from the bottom to the top of the food chain.

For example, if an anchovy eats 10 plankton contaminated with 10 mg of Hg the anchovy would have accumulated 100 mg of Hg. If a catfish eats 5 anchovies it would have accumulated 500 mg of Hg. If a King Mackerel eats 4 cat fish it would have accumulated 20,000 mg of Hg. If a human eats 2 King Mackerel it would consume 40,000 mg of Hg as opposed to 1,000 mg from eating 2 catfish.

Concentrations of Concern in Freshwater fish

Regulations Regarding Human Consumption

The FDA has 3 recommendations for selecting and eating fish

1. Do not eat predatory fish high in mercury
2. Eat up to 12 ounces a week of a variety of fish and shellfish that are lower in mercury.
3. Check local advisories about the safety of fish caught by family and friends at your local water sources

Mechanism of Toxicity

As mentioned earlier, toxicity increases through bioaccumulation and biomagnification. However, toxicity will decline if an individual stops eating fish or eats fish with lower concentrations of mercury. In humans, about half the body burden of mercury can be eliminated in 70 days if no mercury is ingested during that time

Mercury in the environment

Mercury in Dorena Lake

Mercury Tuna version of Mc Donald's Supersize me experiment