Biological Magnification

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Biological Magnification

• Bill Addo, Haram Chang, Jay Chen, and Nabila
  Akthar
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• Biology SB1

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What is Biological Magnification?

• Biological Magnification, also known as
  Biomagnification, is the increase of substances
  that occurs in food chains. 
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• These substances are usually found in
  contaminated environments. Substances, such as
  pesticides and mercury, are absorbed by organisms
  due to their environment or the food they
  consume. The substance then accumulates inside
  the cells. 
•  When an organism higher in the food chain eats
  multiple organisms below, each of them containing
  some of the toxins, the toxins becomes more
  concentrated in the higher food chain. Since this
  continues throughout the food chain, organisms
  higher in the food chain are the ones who will
  obtain the most toxins.
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Bioaccumulation

• Biological Magnification is often related with
  Bioaccumulation, which is the increase of the
  toxic substance in an organisms body. 
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• These two terms are different 
• Accumulation pertains to harmful substances in a
  living organism's body and its effects. 
• Magnification deals with the substance being
  passed along the food chain.
• Bioaccumulation will cause a number of problems
  within the body that contains it. 

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How Biomagnification affects animals

• A common example of Biomagnification and
  Bioaccumulation is the use of DDT in the 1960's
  and 1970s. DDT, or dichlorodiphenyltrichloroethan
  e, was overly used by humans as a pesticide. It
  soon found its way into the environment. 
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• DDT and other toxins eventually climbed up the
  food chain, and affected the bald eagles, nearly
  driving them to extinction. The DDT was absorbed
  by organisms which the bald eagles hunted, such
  as fish and carrion. Each bald eagle would eat
  multiple numbers of these fish and carrion.
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• The DDT would accumulate inside each of the
  eagles' bodies. The DDT would sterelize the birds
  or cause them to make fragile eggs that would
  break easily. This caused the birds population to
  dwindle rapidly.

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Bald Eagle Population
Figure 1

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• http//www.fws.gov/midwest/eagle/population/chtofp
  rs.html

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How DDT rises in a food chain
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Mercury

• Mercury is a natural substance, that is found in
  very small quantities in the ocean. Human
  interference with the environment, causes higher
  levels of mercury in the ocean. 
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• Algae, a producer, consistently absorbs the
  mercury which is found in its environment.
  However, it excretes it slowly. Often, zoo
  plankton will consume the algae and the mercury
  along with it. 
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• The plankton is then consumed by small fish,
  which is in turn consumed by larger fishes.
  Eventually, the fishes end up on human dinner
  tables. Humans, who consume fishes high in
  mercury, will easily become ill from mercury
  poisoning.

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Biological Magnification of Mercury
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The Biological Magnification of DDT in a marine
ecosystem.
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Toxins that Biomagnify

• DDT and Mercury are not the only toxin that
  biomagnifies. Other examples include, but are not
  limited to 
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• PCB'S (polychlorinated biphenyls) used in
  insulators, as a plasticizer, and fire retardant.
  It biomagnifies, impairs reproduction and is
  widespread in aquatic systems.
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• Cyanide is used in leaching gold and in fishing.
  It is a dangerous toxin and is known to have
  effects on coral reefs. 
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• Selenium is concentrated by farming desert soils.
  It is toxic and causes reproductive failures in
  organisms. 
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• Heavy metals such as mercury, copper, nickel,
  zinc, and lead affect the nervous system and they
  may affect reproduction. 

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Toxins in Bodies of Water
Figure 2
http//www.epa.gov/med/grosseile_site/indicators/i
mages/ddtwalleye-fig7.gif
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Toxins in Bodies of Water
Figure 3
http//www.epa.gov/med/grosseile_site/indicators/e
rie_fish.html
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Toxins in Bodies of Water
Figure 4
http//www.epa.gov/med/grosseile_site/indicators/e
rie_fish.html
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More Biological Magnification
Figure 5
http//jan.ucc.nau.edu/doetqp-p/courses/env470/Le
ctures/lec39/Lec39.htm
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Why We Should Care

• Ironically, biomagnification and bioaccumulation
  are caused by humans but also have a profound
  impact on us. 
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• It can lead to neurological effects such as
  mental retardation in infants who contract it
  through their mothers.
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• A weakened immune system is also the result of
  biomagnification.
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• Some cancers are also linked through ingesting
  these toxins.
• It can also lead to organ failure in both animals
  and humans.
• Since some animals have weaker immune systems
  then humans, they will die faster which can lead
  to extinction if it continues.

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Prevention of Biomagnification

• In an attempt to eradicate biomagnification, the
  U.S. and several countries worldwide have placed
  a ban on the use of DDT.
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• People are trying to prevent harmful substances
  such as oil and human waste from being dumped in
  water.
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• Landfills are also trying to get rid of these
  substances because they can seep into ground
  water.
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Special Thanks / Citations

• Information
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• http//en.wikipedia.org/wiki/Biomagnification
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•  http//toxics.usgs.gov/definitions/biomagnificati
  on.html
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• http//www.marietta.edu/biol/102/2bioma95.html 
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• http//www.epa.gov/med/grosseile_site/indicators/e
  rie_fish.html
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• http//jan.ucc.nau.edu/doetqp-p/courses/env470/Le
  ctures/lec39/Lec39.htm

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Special Thanks / Citations Continued

• Pictures
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• http//www.calgoldrush.com/graphics/images/contami
  nation.gif
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• http//image.wistatutor.com/content/ecosystem/biol
  ogical-magnification.jpeg 
• http//www.corg/html/stitch.php?s98965698293378i
  d34347859802049fkeep.
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• http//www.fws.gov/midwest/eagle/population/chtofp
  rs.html