1.5 - Humans And Pollution

Question 1

Define pollution

Answer 1

Pollution is the contamination of the earth and atmosphere to such an extent that normal enviroment processes are adversely affected. They are added to the eviroment faster than they can be removed

Question 2

Explain the difference using examples between the primary and secondary pollutants.

Answer 2

Primary - directly created and active on emissions e.g. carbon monoxide from incomplete combustion

Secondary - crated by primary pollutants undergoing chemical change e.g. when so2 reacts with water it form sulphuric acid

Question 3

List 5 types of pollutants

Answer 3

• inorganic substance - sulphur dioxide from a factory entering the air
• organic substance - manure used as fertiliser on farmland washing into a lake
• light - a bright garden light shining onto the neighbours house
• sound - disruptive noise coming from a busy road near a housing estate
• heat - warm water entering a river from a factory

Question 4

State one example of point source and non point souse pollution

Answer 4

Point source pollution - discrete source of contaminants waste disposal pipe of sewage works into river

Non point source pollution - dispersed source of contaminants gases from exhausted system of cars

Question 5

Explain how point and non point source pollutant differ

Answer 5

Point source pollutants come form a single indtifable source so it is easier to see who is causing it and how to manage it. Non point source pollution because of its many sources is harder to track and manage

Question 6

Air quality in Beijing is particularly poor as a result of coal-burning amongst other pollutants.
This is an example of chronic pollution. Using an example of acute pollution to support your answer, explain why Beijing air pollution is an example of chronic pollution.

Answer 6

Acute pollution occurs after a shot, intense exposure and symptoms are usually experienced within hours e.g. gulf oil spill. Pollution due to the coal burning in china is chronic as it results in low level, long term exposure and the symptoms develop much later

Question 7

Some pollutants are considered to be persistent and others are biodegradable. Using an example of each to support your answer, explain what these terms mean.

Answer 7

Persistent pollutants:
- resistant to breaking down and can remain active in the enviroment for a long time meaning they bioaccumulate in animal tissue
E.g. DTT

Biodegradable pollutants:
- so not presidir in the environment, not stored in biological matter or passed along food chains. They are broken down by decomposes, heat or light e.g. glyphosate

Question 8

State 2 uses of DTT

Answer 8

Used to control live that spread typhus and mosquitos that cause malaria; used in farming as an insecticide

Question 9

With reference to bio magnification, describe the harmful effects of DDT on birds

Answer 9

Biomagnification is the process whereby the concentration of a chemical increased at each tropic level. As DDT is persistent it will become more and more concentrated se it passes from soil to insect to insect eating bird. The birds have thinning egg shells due to the high concentrations of DEE (breakdown product of DTT)

Question 10

List some potential impacts of DTT on humans

Answer 10

• increased incidence of asthma and or diabetes in farmers, higher risk of liver, breast and pancreatic cancer, increased pregnancy and fertility issues

Question 11

Summarise Rachel Carson’s silent spring book had on the public opinion on DDT use

Answer 11

General public responded well, public awareness was high tended about the impact that human activity could have on the environment. Significant moment in enviromental history

Question 12

Evaluate the use of DDT and justify your own opinion on its use

Answer 12

Malaria is a public health challenge in many parts of the world resulting in about 1 million deaths. DDT is an effective way of controlling mosquitos and is affordable as many of the countries most affected are poor.
However it is persistent pollutant that has negative impact on enviomrental and human health, some of which are not clearly seen yet. An alternative to DDT should be found but until it is the use of DDT should be clearly regulated

Question 13

Suggest possible management strategies for plastics at each three levels

Answer 13

1. Human activity: Altering human activity
   - education on impact of pollution
   - reduction in the consumption of plastics with increased proces
   - financial incentives for recycling
   - provide alternatives
2. Release of pollutants into atmosphere: controlling release of pollutants
   - legislations against plastic pollutants
   - development of recycling
   - development technology to break down and reduce plastics
3. Impact of pollutant on ecosystem: clean up and restoration of damaged systems
   - beach clean ups
   - removing plastic from the envomrent
   - education