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Biomagnification
It is also known as bioamplification or biological
magnification
It is the increase in concentration of a pollutant that occurs
in a food chain as a consequence of:
1
...
Bioenergetics in the food chain
3
...

•e
...
Pollutants in rivers or lakes are taken up by
microorganisms like plankton and are eaten by aquatic
organisms such as fish, which in turn are eaten by large birds,
animals and humans
...


As a result,organisms at the top of the food chain
generally suffer greater harm from a persistent toxin or
pollutant than those at lower levels

Because
•At each level of the food chain there is a lot of energy
loss, a predator must consume many prey, including all of
their lipophilic substances and fats which carries the
pollutant, which then accumulates in the fats of the
predator
...
e
...
They enter the
organism through contaminated air, water, or food and are
very slowly metabolized or excreted
...
Biomagnification
•Bioaccumulation is the concentration of pollutant from the
environment which occurs within a trophic level, i
...
one
level of a food chain, usually the first organism in the food
chain

•Where as biomagnification is the concentration of pollutant
across the food chain

We are concerned about these phenomena because together
they mean that even small concentrations of chemicals in the
environment can find their way into organisms in high enough
dosages to cause problems
...
long-lived
2
...
soluble in fats
4
...
short lived pollutant
• Pollutants that dissolve in
fats(Persistent pollutants)
are retained for a long time
...

• They accumulate in fatty
tissues of an organism if the
organism lacks enzymes to
degrade them
...

• If it is not mobile, it will stay
in one place and is unlikely
to be taken up by
organisms
...


•DDT :dichloro diphenyl trichloroethane
...
5 kg
6
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13 kg
1
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78 kg
0
...


•In mammals, we often test the milk
...

•The substance(pollutant) can also be taken up by organism
from surrounding water by non dietary routes
...
g
...


Bioconcentration factor can be expressed as:
The ratio of the concentration of a chemical in an organism
to the concentration of the chemical in the surrounding
environment
...


•A high BCF can lead to health problems such as genetic
mutations passed on to offsprings

In fish populations increasing numbers of fish born with
ambiguous genitalia have been identified in waterways
contaminated with pharmaceuticals
...
[organisations :Toxics
Link and DISHA on 2012]
•The trend is applicable across the country
•While 52 cases had mercury concentrates in excess of the
Prevention of Food Adulteration (PFA) Act standards of 0
...
25 ppm
PFA stipulations
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High level of mercury causes:
▪neurotoxicity and impairs motor skills
▪stunts psychological development and growth
▪can cause serious mental disorders over a gradual period
of time

Biodiversity Research Institute in Maine ,August 2013
estimated that 83% of fish worldwide have unsafe mercury levels
Over 50% of Asian population have more than the 5ug/ml mercury level
in blood
Cause for global concern because:
•Most Seafood is imported and exported
•Pollution is World-wide problem, requires cooperation of various
nations
...
g

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