1.5 humans and pollusion Flashcards
what is the definition of a pollutant?
pollution is the adition of a substanse or agent to an envirment through human acitivity,
at a rate greater than that at which it can be rendered armless by the envirment,
and which has an applicable effect on the organisms of that envirment.
pollutants can be catagorised as ‘secondary’ and primary’ what is the difference? examplain with examples?
Primary- directly created and activated on emmisson. E.g carbon manoxide from incomplete combustion.
Secondary- created by primary pollutants under going hcmeical or physical change. E.g when so2 reacts with water it forms carbonic acid.
what are the diffrent forms a pollutant can be?
inorganic substanse, organic substanse, light, sound, thermal energy, invasive species, biological agents and heat.
can you give an example of an inorganic substance that is a polluter?
sulpher dioxide from a factory enetering the air.
can you give an example of an organic substance that is a polluter?
manue used as fertilizer on farmland washing into a lake.
can you give an example of light as a polluter?
a bright garden light shining into the nabours house
can you give an example of sound as a polluter?
disruptive noise comming from a busy road near a hpusing estate
can you give an example of heat as a polluter?
warm water from a factory flowing into a rivier.
give an example of point sourse pollution?
direct source of contaminents- waste disposal pipe of sewage works into river.
give an exmaple of non-point souce pollution?
dispersed soruce of contaminents- gasses from exhaust sytems on cars.
explain how point-sorce and non-point source pollution differ?
point source pollution come from a single, idenitifiable source, so it is easeir to see who is causing it and how to manage it.
non-point source pollusion has many sources, and is therefore harder to track and manage.
what is acute pollusion?
accute pollution occurs after a short, intesne exposion to a pollutant. Symotoms are usally experinced within hours e.g gulf oil spill.
what is chronic pollution?
chronic pollusion occurs after a long term, low level exposion, and the symtoms develop much laster.
some pollustants are considered persitant while otheres are considered biodigradible, using an example, expain the diffrence.
persistant pollutants are resistant to breaking down and can remain active in the anivemtn for a long time, menaing they can bioaccumulate in animal tissue e.g DDT
Biodigradable pollutants do not persiti in the envirment, not stored in biodigradable matter or apssed alongfood chains. They are broken down by decomposers, heat or light E.g glyphosate
state two uses of DDT?
1) used to controle lice that spread typhus and mosquitoes that carried malaria.
2) used in farming as a insectide
with reference to biomagnification, discribe the harmful effects of DDT on birds?
biomagnification is the process by which the consentration of a chemical increases at each trophic level.
As DDT is persistant, it will become more and more consentrated as it passes from sil, to insect to insect eating bird.
The birds get thinning egg shells due to the high concentration of DDE, which is the break-down product of DDT.
list some of the potntional harmfull impact of DDT on humans?
increased incidents of athsma and diabities in farmers, higher risk of liver, breast and pancrious cancer. Increased infertility and pregancy issues.
evaluate the use of DDT?
Maleria is a publish health challange in many parts of the world resulting in about 1 million deaths annuallly. DDT is effectove in controlling mosquitoes and it is afforable, which is impriamt as malargia prone counties tend to be LIC.
However, it is a pissistant pollutant that has a negative impact on envitmental and human health, some of which are still unknown.
An alternative to DDT should be found until then, the use of DDT must be closly regulated.
what are the three ways of making chnage in ESS?
Legistantion,
Education
MItigation
