Water Pollution: Pesticides

Question 1

Name the principal properties of pesticides

Answer 1

1. specificity
2. Persistence
3. Bioaccumulation
4. Biomagnification
5. Mobility

Question 2

Name the direct effects of pesticide pollution

Answer 2

• harm non target species by being toxic
• sub lethal doses may inhibit metabolic processes and cause ill health
• high doses may kill
• even lower doses may cause extinction by reducing breeding rates

Question 3

Name the indirect effects of pesticide pollution

Answer 3

• reduction of food availability (it their food species is affected)
• predators may become more commun

Question 4

Name the different groups of insecticides

Answer 4

Organochlorine
Organophosphate
Pyrethroids

Question 5

Explain what are organochlorines and how they affect living organisms

Answer 5

• high insect toxicity
• low mammal toxicity
• persistant and liposolubles —> bioaccumulation and biomagnification

Question 6

Explain what are organophosphates and how they affect living organisms

Answer 6

• not persistant or liposoluble
• toxic to mammal (dangerous while they are being used and soon afterwards)
• sheep farmers exposed suffered damage to nervous system (paralysis)

Question 7

Name the methods to reduce pesticide pollution

Answer 7

1. Restriction on use
2. Use of non-persistant pesticides
3. Use of more specific pesticides
4. Use of more systemic pesticides
5. Biological control and other non-chemical techniques
6. Pest resistant crops
7. Better application techniques