Pollution - Properties Flashcards
How can pollution be defined?
The introduction of contaminants into the natural environment which cause adverse change (harmful substance or energy released)
Which human activities can cause pollution?
- Fossil fuel combustion
- Landfill waste
- Oil spills
- Fertiliser and pesticide use
Which factors impact pollutant behaviour in the atmosphere?
- Presence of H2O
- Wind velocity and direction
- Density
- Topography and altitude
What are examples of gas pollutants?
- CO2
- CO
- NOx
- CH4
What are examples liquid pollutants?
- Pesticides
- AMD
- Oil
- Chemicals
What are examples of solid pollutants?
- Fertiliser
- Plastics
- Heavy metals
- Particulates
How does physical state impact solid pollutant dispersal?
Disperse more slowly than liquid and gas pollutants
How does physical state impact liquid pollutant dispersal?
Rapid dispersal but can become concentrated behind a dam
How does physical state impact gas pollutant dispersal?
Usually rapid dispersal unless a temperature inversion is present
What can liquid and gas pollutants cause?
Trans-boundary pollution
What is energy form?
Some pollutants are in the form of energy (e.g. heat, noise, ionising radiation)
What is density?
Mass per unit volume (impacts dispersal)
What are examples of pollutants with different densities?
High = Heavy metals
Low = CO2
What is persistence?
The length of time a pollutant remains in the environment (environmental half-life)
What are examples of pollutants with different persistence?
High = CFCs
Low = Sewage
What is toxicity?
How poisonous a substance is to living organisms
What are examples of toxic pollutants?
Lead, CO (binds to haemoglobin)
What is specificity?
How targeted a pollutant is
What is an example of a pollutant with high specificity?
Pesticides/insecticides
What is reactivity?
How reactive a pollutant is (alters toxicity)
What are examples of pollutants with different reactivity?
High = NOx
Low = CFCs (unless UV is present)
What is adsorption?
The ability to adhere/stick to a solid surface
What are examples of pollutants with different adsorption?
High = Heavy metals
Low = CO
What is solubility?
Pollutants may become soluble in water or fats (water- and lipo-soluble)
What are example of soluble pollutants?
Water = Nitrates
Lipo = Mercury
What is bioaccumulation?
The build-up of a toxin within a living organism (usually lipo-soluble as water-soluble pollutants are easily excreted?
What is biomagnification?
A toxin becomes more concentrated as it moved up trophic levels (e.g. mercury in tuna fish)
What is synergism?
The ability of a pollutant to interact with another pollutant and become more toxic
What is an example of synergism?
Tropospheric O3 and SO2 (damages leaf cuticles)
What is mutagenic action?
The ability of a pollutant to change DNA structure which will be passed on to offspring
What are examples of mutagenic action?
- Ionising radiation
- UV light
- Cadmium
What is carcinogenic action?
The ability of a pollutant to cause cancer due to cell multiplication
What is an example of carcinogenic action?
UV can cause skin cancer
What is teratogenic action?
The ability of a pollutant to cause birth abnormalities due to a change in gene expression (no DNA change)
What is an example of teratogenic action?
Mercury
What is mobility?
The ability of a pollutant to move in the environment (impacted by S/L/G)
What are examples of pollutants with different mobility?
High mobility = CFCs
Low mobility = Lead dust (high density so deposited closer to the source)
What is a primary pollutant?
A pollutant released directly into the atmosphere (CO2, NOx)
What is a secondary pollutant?
A pollutant formed by the reaction of a primary pollutant in the atmosphere (tropospheric O3)
How can pollutant sources be defined?
- Point (identifiable source)
- Diffuse (no single identifiable source)
Which environmental factors impact pollutant dispersal?
- Air/water velocity and direction
- Topography
- Adsorbent materials
- Temperature inversions
Which environmental factors impact pollutant degradations?
- Temperature
- Oxygen
- Light levels
- pH
- Pollutant interactions
How do adsorbent materials impact pollutant dispersal?
Clay particles could immobilise a pollutant
How does oxygen impact pollutant degradation
- Chemical and biological reactions
- Oxidation impacts solubility
How do light levels impact pollutant degradation?
Provides activation energy for reactions
How does pH impact pollutant degradation?
Heavy metals such as lead are more soluble in acidic conditions (increases mobility)
