pollutant properties

HideShow resource information
View mindmap
  • Pollutant Properties
    • Toxicity
      • Measure of how poisonous a material is
      • Damages Proteins
      • Examples
        • Carbon Monoxide
          • Binds to haemoglobin in blood, prevents it from carrying oxygen
        • Lead
          • Inhibits enzymes in nerve cells, affects polarisation processes
        • DDT
          • Prevents passage of nerve impulses, causes leakage of ions, causing the nerve to fire at incorrect times
        • Acids
          • Change shape of cell membrane by affecting hydrogen bonds, also inhibits enzymes
    • Non Toxic pollutants that can indirectly harm
      • Sewage
        • Causes deoxygenation of lakes and rivers, leading to animal deaths
      • Greenhouse Gases
        • Heat the earth changing habitats on a planetary scale
      • CFCs
        • Create holes in the ozone layer that causes UV rays to get through easier, higher levels of cataracts and skin cancer
    • Specificity
      • Different organisms can be affected by the same toxin
        • Pyrethroid
          • Affects both mammals and insects, however insects are more sensitive to this toxin
            • Therefore farmers can apply doses that are lethal  to insects but are not lethal to mammals (I.E. livestock and humans)
    • Persistence
      • Measure of how long it takes a pollutant to break down chemically
        • This name is not used for substances that will not break down such as elements or very stable compounds
      • Examples
        • CFCs
          • Chemically stable so may remain in the atmosphere for many decades
        • DDT
          • Will gradually stable but still is found occasionally in wildlife 30 years after it was banned
        • Heavy Metals
          • Lead, mercury and other elements do not break down as there is nothing for them to break down into
      • Non-persistent Pollutants
        • Sewage
          • As long as the conditions are warm with plenty of oxygen the sewage will break down rapidly as the conditons are right for the bacteria
        • Pyrethroid
          • Breaks down rapidly in comparison to other pesticides such as DDT
    • Biodegradability
      • Degradation
        • Process of chemical breakdown
      • The action by which pollutants are broken down by decomposers (bacteria and fungi)
        • Affected by temperature and oxygen availability
      • Biodegradable Pollutants
        • Sewage
        • Paper
        • Cardboard
      • Less Biodegradable Pollutants
        • Plastics
        • DDT
    • Mobility
      • How easily a pollutant moves through the environment
      • More mobile pollutants cause problems over a large area but will be less comcentrated
      • Examples
        • Sulphur dioxide
          • Can travel long distances in clouds before it causes acid rain
        • Smoke particles
          • easily washed out of the atmosphere so do not travel far unless they rise high into the atmosphere quickly
        • Suspended Sediments
          • Are carried different lengths depending on size of debris and speed of water flow
    • Solubility
      • Measure of ease of molecules separating and dispersing in liquid
      • Water Solubility
        • materials dissolving in water are very mobile in the hydrosphere
      • Liposolubility
        • If dissolve in fats, can remain in bodies of animals for a very long time
        • Liposoluble examples
          • Chlorinated organic compounds
            • Organochlorine insecticides
            • Dioxins
            • PCBs
          • Heavy Metals
            • Mercury
            • Lead
    • Bioaccumulation
      • Process by which pollutant are absorbed and stored in living organisms
      • Exposure to small doses over long periods of time cause chemicals to accumulate
        • This build up causes the problems
      • Mainly Liposoluble pollutants as they build up in the fat
        • Water soluble pollutants excreted too easily
      • Chlorinated organic compounds
        • Organochlorine insecticides
        • PCBs
        • Dioxins
      • Heavy Metals
        • Mercury
        • Lead
    • Biomagnification
      • Increase in the concentration of a pollutant as it travels up the food chain

Comments

No comments have yet been made

Similar Environmental Science/Studies resources:

See all Environmental Science/Studies resources »See all pollution resources »