General Ecology ( Zoo 407)

1. Instructor

2. • Define biological magnification
• Distinguish biomagnification,
bioaccumulation,
bioconcentration and
Biodilution
• Explain the causes and effects
of biological magnification
• Outline remedies in diminishing
biological accumulation within the
ecosystem

3.  Biomagnification, also known as
Bioamplification or Biological
magnification
 The tendency of pollutants to become
concentrated in successive trophic
levels.
 It is the increasing concentration of a
substance, such as a toxic chemical, in
the tissues of tolerant organisms at
successively higher levels in a food
chain.
• It occurs when organisms at the
bottom of the food chain
concentrate the material above its
concentration in the surrounding
soil or water.
• The problem comes up when a
pollutant, such as DDT or
mercury/ PCB's is present in the
environment.

4. • Biological magnification often refers
to the process whereby certain
substances such as pesticides or heavy
metals work their way into lakes,
rivers and the ocean.
• And then move up the food chain in
progressively greater concentrations
as they are incorporated into the diet
of aquatic organisms such as
zooplankton.
• Which in turn are eaten perhaps
by fish, which then may be eaten
by bigger fish, large birds,
animals, or humans.
• Chemically, these pollutants
resemble essential inorganic
nutrients and are brought into the
producer's body and stored "by
mistake".

6. • This is the First Step in
biomagnifications; the pollutant is at a
higher concentration inside the
producer than it is in the environment.
• The Second Stage of
biomagnifications occur when the
producer is eaten.
 BIOMAGNIFICATION,
BIOACCUMULATION, AND
BIOCONCENTRATION
• Bioaccumulation occurs within a
trophic level, and is the increase
in the concentration of a substance
in certain tissues of organisms'
bodies due to absorption from
food (Nutrients) from the
environment
• Bioconcentration is defined as
occurring when uptake from the
water is greater than excretion

8. • Thus, Bioconcentration and
Bioaccumulation occur within an
organism, and Biomagnification
occurs across trophic (food chain)
levels.
• Biodilution is also a process that
occurs to all trophic levels in an
aquatic environment; it is the
opposite of biomagnification, thus
when a pollutant gets smaller in
concentration as it progresses up a
food web.
 In order for a pollutant to
biomagnifies, the following
conditions must be met:
1. The pollutant must be long-lived.
2. The pollutant must be
concentrated by the producers.
3. The pollutant must be fat-soluble

9. • This increase of toxins can occur as a
result of:
1. Persistence – where the substance
cannot be broken down by
environmental processes
2. Food chain energetics – where the
substance's concentration increases
progressively as it moves up a food
chain
3. Low or non-existent rate of
internal degradation or
excretion of the substance –
often due to water-insolubility
Biomagnification is the build
up of toxins in a food chain. As
the trophic level increases in a
food chain, the amount of toxic
build up increases

11. • Lipid, (lipophilic) or fat soluble
substances cannot be diluted, broken
down, or excreted in urine, a water-
based medium, and so accumulate in
fatty tissues of an organism, if the
organism lacks enzymes to degrade
them.
• When eaten by another organism, fats
are absorbed in the gut, carrying the
substance, which then accumulates in
the fats of the predator.
• Since 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.
• Biological magnification occurs
by increasing the toxicity of
poisonous substances as those
substances move up the food chain.

12. • An example of biological magnification
and its dangers is any small fish
that eats plankton that has been
tainted with mercury.
• Hundreds of small fish might
then contain just few parts of the
mercury, not enough to cause
major harm.

15. The field of biology that focuses on
the negative effects of harmful
chemicals and toxins on different
ecosystems and the living
organisms present there is called
“Ecotoxicology“.
• Biological magnification, despite
being a biological phenomenon, is
often caused and triggered by
anthropogenic factors.
• Some of these causes include:
1. Organic Contaminants
2. Agricultural and Industrial
wastes
3. Pollution from Plastics
(Pollution)
4. Heavy Metals from Mining

16. • Organic contaminants like
carbon, nitrogen, and
phosphorus are known to be
very abundant in the natural
environment.
• As a general rule, too much
of everything can be very
bad.
• While these chemicals are known to be
necessary for organism survival, their
excessive amounts in ecosystems can
lead to a phenomenon called
Eutrophication
• As a result, living organisms like
prokaryotes and algae exhibit rapid and
exponential growth. Because of their
excessive population, other organisms
die as a result of oxygen depletion.

17. • In the recent years, pollution
of oceans due to excessive
plastic disposal has become a
significant global
environmental problem.
• For instance, a substance present
in plastics, called as Bisphenol A,
is considered as one of the leading
chemicals that pollute the
environment.

18. • Heavy metal refers to any metallic
chemical element that has a relatively
high density and is toxic or poisonous
at low concentrations.
• Mining include activities that result in
the discharge of heavy metal deposits
(i.e., zinc, silver, gold, cobalt) into
aquatic environments.
• As a result, levels of chemical toxicity
in these areas increases tremendously.
• Aside from polluting aquatic
plants, metal pollution of water
can also contaminate drinking
water systems.
• Disturbingly, metal
contamination is considered to be
very hard to treat.
 Examples include:

23. • Chemicals from inorganic
fertilizers, herbicides, pesticides,
and fungicides are often known to
contaminate soils and bodies of
water via runoff from rains and
storms.
• Aside from that, industrial wastes
from factories and other industrial
operations can also contribute to the
release of toxic chemicals and heavy
metals to the food chain.

24. • As alluded to earlier, biological
magnification, especially when not
controlled, can be fatal to living
organisms.
• The following are just some of its
negative effects.
1. Pollutant Build up
2. Bioaccumulation in Fat Cells
3. Effects on The Health of
Organisms

25. • Pollutant build up, especially
from those persistent
chemical elements, is one of
the most common effects of
biological magnification.
• Being made up of a single
element, these chemicals
accumulate fast, and when
they do, they become very
hard to biodegrade.
• Water plants and algae can easily
accumulate harmful chemicals
because they share similar qualities
with the kinds of nutrients these
organisms need for growth

26. • If by any chance the chemical is still
present within the plant after being
eaten by a larger organism (in the
food chain), the next organism will
get to absorb that chemical as well.
• And as it continues to consume more
of those plants, the chances that the
larger organism absorbs more
chemicals will also increase.
• One of the most common
examples of biomagnification is
algal bloom that often leads to red
tide.
• In this case, excessive amounts of
chemicals (presumed by the
organism as a nutrient) cause the
overgrowth of the alga known as
Karenia brevis.

27. • This alga, which is color red due
to the pigment Xanthophyll, is
capable of producing a certain
kind of neurotoxin that can be
deadly to organisms that
consume them.
• Symptoms of poisoning from red
tide include numbness and
digestive problems.

28. Algal Bloom

29. • While some toxins are easily removed
from the body, there are also those
foreign chemical substances that tend
to be stored within the Fat Cells
(Adipose tissues) of organisms.
• Such occurrence is very hard to treat
because some of these chemicals can
only be removed using specific
enzymes.
• If the organism is lucky enough,
it may have the capability to
produce enzymes that can
degrade such chemical.
• However, if otherwise, the
chemical substance may
gradually accumulate inside its
fat cells and become
irrecoverable.

30. • As alluded to earlier, organisms
located at the higher level of the
food chain also harbor the higher
risks for biomagnification.
• Nevertheless, the mere build-up
of these harmful chemicals inside
living cells and tissues can pose a
great risk to health.
• Mercury, for instance, is a toxic
chemical that affects the Central and
Peripheral Nervous System as well
as Cardiovascular System.
• Because of this, the ingestion of
mercury can cause a wide variety of
diseases; Reproductive problems,
Mutations, Birth abnormalities,
Behavioral changes, and Death.

32. • Alarmingly, toxic chemicals like
mercury tend to settle on the ocean
floor and are taken up by organisms
that feed on plants and sediments.
• Environmental problems like
biological magnification have already
been present for a long time
• Humans are the biggest threat to
the ecosystem, and ironically, we
are also the ones who can take
actions to prevent its destruction.
• Knowledge and awareness are
the first steps to doing this.

34. • Timely concerns about
environmental sustainability
intensify the need to teach people
about the relationship between
human health and the states of
our ecosystems.
• By engaging in activities, we
develop a greater understanding
of the core values between
humans and environment

35. References:
• https://en.wikipedia.org/wiki/Biomag
nification
• https://www.bioexplorer.net/biological
-magnification.html/
• https://www.biologycorner.com/works
heets/articles/biological_magnificatio
n.html
• “Biomagnification facts,
information, pictures |
Encyclopedia.com articles about
Biomagnification”. Accessed
December 25, 2017
• “Biology The Phosphorus Cycle –
Shmoop Biology”. Accessed
December 25, 2017.