N5 Biology Assignment

National 5 Biology Assignment

Aim

To investigate the effects of using DDT as a pesticide on the environment.

Application

DDT is a chemical pesticide which came into use during WW2 which it was used to control diseases and pests such as typhus, body lice, bubonic plague and malaria.  DDT was very widely used because it is very effective, but today it is only really used in developing countries.  

Over the years, more research has been conducted into DDT, and the effects it has on the environment.  It was found that it remains in the environment for a considerable length of time, and it also accumulates in the bodies of organisms which causes detrimental effects on wildlife.  The levels of DDT increase as the chemical is passed along the food chain, and can be fatal to top-level consumers.  This is called bioaccumulation.

Sources

Source 1

One source that I used to research my aim was www.hubpages.com which was very useful in helping me to write my assignment as it contained key information which was relevant to my topic as it contained information about the effects of using DDT on wildlife.  

Raw Data:

[pic 1]

Processed Data:

[pic 2]

Analysis:

This graph shows the bioaccumulation of DDT in a food chain, with the concentration of DDT increasing 528,000 times from the water concentration to the Cormorant.  A link has been found between DDT use and cancer, with mammals showing increased rates of liver cancer after exposure.  This could be extremely harmful to ecosystems, leading to a decrease in biodiversity and some species potentially becoming extinct.  [pic 3]

Source 2

Another source that I used to research my aim was www.cfs.gov.hk which was very useful in helping me to write my assignment.  This source is reliable as the research was carried out by the Centre for Food Safety.

Raw Data:

[pic 4]

Processed data:

[pic 5]

Analysis:

This data shows that we actually consume a reasonable amount of DDT per day, and many people are probably unaware of this.  Although these levels may not be fatal to humans, they would be fatal in smaller organisms.  Also, these figures are simply an average amount, and the Centre for Food Safety stated in their report that the exposure to DDT in secondary school students could range between “0.053 (lower bound estimate) and 0.238 (upper bound estimate) μg/kg bw/day”.  This could also potentially damage our health as humans by causing cancer to develop, as this also happens with animals.

Conclusion

In conclusion, I have found that using DDT as a pesticide has an extremely detrimental effect on the environment and wildlife, as the levels of toxicity can be fatal in top-level consumers but can also effect smaller organisms too.  I also found that humans may be affected by the toxicity of DDT as my research showed a link between its use and cancers developing in mammals.

References/Bibliography

1. http://hubpages.com/politics/Bioaccumulation-and-Biomagnification# (Source 1) – 21/02/2016
2. http://www.cfs.gov.hk/english/programme/programme_rafs/programme_rafs_fc_01_01_ddt.html (Source 2) - 21/02/2016
3. http://npic.orst.edu/factsheets/ddtgen.pdf - 21/02/2016

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