Issues of Pesticide + DDT
Issues of Pesticide + DDT
Issues of Pesticide + DDT
Tanvi LenaTiffany
Pest may develop resistance to the specific chemical
This happens through natural selection
MAIN PROBLEM It makes existing pesticide useless, so another must be found
Another problem is that pesticides cause environmental damage
BIOACCUMULATION BIOMAGNIFICATION
They build up in the tissues of They build up and become
organisms as they don’t get concentrated along food chains
excreted
B E EA S Y TO CONTROL PEST
A P P LY E F F E C T I V E LY
NOT
BE
A C CU MU L AT
BIODEGRADABLE
E
B E S A F E TO
B E S P E CI F I C
T R A N S P O RT
PERSISTENT
- r e m a in in g ac tiv e in th e en v ir o nm en t f o r m an y y ear s—1 0 y ear s.
- I t wo n ’t h a v e d eg r ad ed to har m less pr o d ucts – so m e to DDE, a po ten t insecticid e;
so m e will h av e sp r ea d to oth er hab itats.
- DDT is ca r r ie d g lo b ally b y win d -id en tified in p o lar ice cap s an d d eserts, th o u san ds o f
k ilo m etr e s a way.
RESISTANT INSECTS
- d e v elo p e d a g e n e tic m utatio n th at pr even ted th em f ro m b ein g killed b y th e
in sec ticid e .
- th e r esista n t in se c ts h ad an adv an tage o ver th e n o n -r esistant o nes
- - > n u m b er s in c r e a se d with every g ener atio n r epr o d uctio n sin ce th ey wer e ab le to
su r v iv e e x p o su r e to th e p esticid e
- - > p assin g o n th eir r esistan ce g en es to th eir off sp r in g . (Natu ral selectio n)
- DDT doesn't just kill pests but it kills any type of insect within the perimeter, including
harmless ones such as butterflies, bees or wasps. Why will cause damage to ecosystems by
disrupting food chains
- DDT is very soluble in fats. When herbivore feeds on plants that are contaminated with
DDT, the insecticide is not broken down or excrete. Instead, bioaccumulation happens: it
becomes concentrated in fatty tissues of the animal. when carnivores eat this herbivore, the
insecticide builds up in concentration along the food chain. This is known as
biomagnification. The high levels of concentration at range of the food chain may be toxic
and lead to the death of top carnivores in the chain. Disrupting the food web of ecosystem.
2. State and explain one reason DDT as an effective insecticide, has been banned.
DDT
1) It is not biodegradable, It can kill other harmless insects, It can bioaccumulate in animals, Bio magnification can
happen
2) -Persistent - remaining active in the environment for many years—10 years. It won’t have degraded to
harmless products, can carried globally by wind.
- Resistant insects- developed a genetic mutation that prevented them from being killed by the insecticide. passing on the
resistance genes to the next offsprings.
- It kills any type of insect within the perimeter, cause damage to ecosystems
-Bioaccumulation and biomagnification
3) Natural selection is a process by which a species changes over time in response to changes in the environment,
or competition between organisms, in order for the species to survive. The members of the species with the most desirable
characteristics are able to produce the best-adapted offspring. If a species is unable to adapt then it is at risk of
becoming extinct. For example, when insects pass on their resistance genes to their offspring due to resistance to DDT
4) Bioaccumulation is the accumulation of insecticides as fatty tissues in an animal, instead of being broken down or
excreted. This then leads to biomagnification where the amount of said fatty tissues are continued to be accumulated and
built up along the food chain, which may eventually lead to the death of the top carnivores as the amount that has been
accumulated becomes toxic. Which leads to a disturbance in the chain.
5) Be easy to apply, It won't accumulate ...
20XX PESTICIDE + DDT 8
CITATION
THANK
YOU!