Unit 2 AOS 1 - Pollution Flashcards
Pollution
When a substance entering or being present in an environment has harmful or poisonous effects
Pollutant
The substance that pollutes.
Dispersal
How pollutants enter the environment
Primary pollutants
Substances released into environment directly from a polluting source. (fossil fuels)
Heavy metals
A metal with an atomic mass greater than that of calcium (mercury, lead, cadmium, arsenic)
Waste
A substance discarded after being deemed no longer useful after the completion of a process. Can become a pollutant if not treated properly (but may not)
Contaminant
A substance present where is does not naturally occur
Pollutant (regarding contaminants)
Contaminant that can result in adverse biological effects to resident biota.
Secondary pollutants
Formed by chemical changes to primary pollutants
What are some atmospheric pollutants (gases)
Gases like:
- CO2
- Carbon monoxide
- nitrogen dioxide
- sulfur dioxide
- ozone
- VOCS
- particulate matter
Water pollution
Caused b a substance that enters waterways at excessive levels
Terrestrial pollution
Imbalance in natural systems caused by humans
Noise pollution
Continuous or recurrent noise that is annoying or physically harmful.
Thermal pollution
Heat from hot water that is discharged from a power plant or factory into a river or lake that can be fatal to aquatic life
Direct pollution
Discharging a pollutant directly from the source into the environment
Point source emissions
Pollutants that come from a single discharge point, like a chimney.
Pollutant sink
process or place that removes a pollutants from the biogeochemical cycle by either storing it for a long time, or turning it into another substance.
Biomagnification
The increasing concentration of a chemical in organisms as it goes up the food chain
Mercury
Naturally occurring heavy metal found in three forms: organic, inorganic, and elemental (metallic)
Indirect pollution
When a pollutant finds its way indirectly into an environment. (nitrogen run-off)
Diffuse source emissions
Enters the environment across a broad area (like fertiliser run-off)
Fugitive emissions
Escape from an instrument or facility separate to any designated outlets
Bioaccumulation
When an organism takes in a substance faster than the body can remove it and the amount of substance in the body increases over time
Bioconcentration
A type of bioaccumulation.
a chemical taken directly from the environment, but not through food.
Local impacts
Small scale impact - affects an area of a few square kms
Global impacts
global and international impact
Inhaled
Taken in through the lungs and absorbed through the membrane surfaces into the bloodstream
Dermal absorption
Absorbed through the skin
Endocrine disruptors
Synthetic or naturally occurring chemicals that affect the hormonal systems in animals
Environmental hazards
Defined as factors of the environment which threaten or impair human health in some way
Regional impacts
large yet distinct are of impact
Exposure
A measure of how much of a pollutant a person is exposed to in a given time
Ingested
Taken in through swallowing (food/drink) and absorbed from digestive system into the liver then to the bloodstream
Toxicity
A measure of the harm (through illness or death) that a substance can cause in organisms
Acute toxicity
The adverse health effect from a single dose of a toxic substance
Chronic toxicity
Adverse health effects of repeated exposure to the material over a prolonged period
Threshold
The level of chemical exposure below which there is no adverse effect and above which there is significant toxicological effect
Lethal dose (LD)
A term to describe the dose of a substance that is sufficient to kill a percentage of an animal within a given time
How is pollutant dispersal affected?
It is affected by its characteristics
“Water is a powerful disperser”
What does this mean?
Means water can transport both water soluble and non-soluble pollutants
What different forms is mercury found in? (Give examples of each)
Organic (Methylmercury)
Inorganic (Mercuric chloride)
Elemental (Metallic) - (hg)
What are some properties of mercury?
is liquid at room temp
conducts electricity
Is toxic as vapour
‘Mercury is persistent’
What does this mean?
Elemental mercury can’t break down into less toxic substances, so stays in the environment.
The Convention on Mercury commits countries to implement:
- bans on new mercury mines
- the phase-out of existing mines
- control measures on air emissions
- regulations on artisanal and small-scale gold mining
What are some properties of Arsenic?
- Grey
- Metallic properties, semi-metal
- High toxicity
- Found naturally
- Inorganic form is the most toxic
- Carcinogen
What are some sources of arsenic?
Bushfires and volcanoes, found in earths crust
What are some man-made sources of Arsenic
glass, mining, paper products, timber treatments
What are some environmental effects of Arsenic
reduced organism health, death of plants and animals, and imbalances of population in ecosystems
What is a carcinogen?
A cancer-causing substance
The impact of pollution can be viewed at what three levels? Define each.
Local - Small scale impact
regional - large yet distinct are of impact
global - global and international impact
What can contribute to illness caused by a specific environmental hazard.
- Environmental factors (housing, climate)
- Demographic factors (socio-economic status)
- Genetics
- Other exposure
What ways can substances be absorbed into the body?
- ingestion
- inhalation
- dermal absorption
The dosage of a chemical pollutant a person receives is affected by:
- respiration rate
- concentration
- frequency of exposure
- length of exposure
- properties of the chemical
- body weight
What are some examples of new potential hazards and risks?
Ozone depletion, GMO and electromagnetic fields
A pollutant is degradable if it _____________
breaks down in the environment due to sunlight, soil and water organisms or other chemical reactions.
what is the endocrine system?
The endocrine system is a set of glands and the hormones they produce.
What glands around the body excrete hormones?
- Pineal gland
- Pituitary gland
- Thyroid gland
- Adrenal gland
- Pancreas
- Ovary
- Testes
Define hormones
Hormones are chemicals that coordinate different functions around the body by carrying messages to the blood in organs.
What types of organisms have endocrine system?
All eukaryotic organisms
What is the function of the endocrine system?
The hormones that the endocrine system produces helps to guide the development, growth, reproduction, and behaviour of animals & humans.
How do endocrine-disrupting chemicals affects the endocrine system?
- EDCs can affect/reduce the production of hormones in endocrine glands, copy or counteract the action of hormones at ‘target tissues’
- Can speed up the metabolism of hormones & therefore reduce their action
What stages of development are most at risk to exposure to EDCs?
- Exposure during early development, like in the womb, or during childhood, can cause permanent effects.
What are some impacts of EDCs that would impact the health of the environment?
- Aquatic animals are particularly affected, especially carnivores as they are at the top of the food chain.
- Eggshells can end up thinning in birds of prey
- Reduction in the frog population.
- Overall, there are many negative effects that primarily impact animals.
Contamination
Is the presence of a substance where it does not naturally occur or is found at concentrations above background levels.
Light pollution
Light from cities and tons at night that interfere with astronomical observations
Pollutant sink
Is a process or place that removes, stores or absorbs the pollutant
eg. carbon dioxide (CO2) dissolving in water both in oceans and freshwater bodies
Pollutant sources
Either point or diffuse sources
Mobile emissions
Come from mobile sources
eg. a motor vechile
Transport mechanisms for pollutants
Air pollutants are generally transported by air circulation (wind) while
Water pollutants are transported via the water cycle through the movement of streams, run-off and tidal currents
Environmental health
Those aspects of public health concerned with the factors, circumstances, and conditions in the environment or surroundings of humans that can have an influence on healthy and wellbeing
Environmental indicators
Are identified and measured as a way of assessing the overall condition of an environment.
Good environmental indicators reflect an understanding of the links between a human activity and its consequence
eg. exhaust from cars decreases air quality in cities
Typical indicators
A Physical environmental indicator, A Chemical environmental indicator, A biological environmental indicator, A socioeconomic environmental indicator
a physical environmental indicator
Measures a physical feature of the environment
eg. the amount of sunlight through water or reaching the forest floor
A chemical environmental indicator
Measures a chemical factor affecting the environment
eg. Ph level or phosphorus level
A biological environmental indicator
Measures effects on a plant or animal
eg. the change over time in the number of a certain plant species in a given area
Salinity
Conductivity measures the amount of inorganic salt materials dissolved in a soil or water sample
Salinity can also be measured by evaporating a given amount of the water and weighing the remaining salt
It is measured in milligrams per litre (mg/L)
Range of tolerance
Chemical and physical conditions within which an organism will live, grow and function normally
What is dosage
What is DDT
