unit 3: science 9- environmental chemistry Flashcards
MSDS’s
Material safety data sheets
They are a form of label that gives information about the harmful substance to the buyer of the product
If describes precautions that should be taken when handling, using, transporting and disposing of the product
It also provides details about heal effects and how to contain or store the product
Transport of hydrocarbons in soil
Contamination of soul by hydrocarbons is a problem throughout Canada
Hydrocarbons are from vehicles and in industry… They contaminate by being carried through water in the soil and spread over a wide area. They can concentrate inside the pores of the grains and not travel very far but cause a difficulty to clean up
Most hydrocarbons are toxic to plants, animals and humans
Impact of the oil spill on people
Many commercial fishers could no longer sell fish
People who relied on wildlife for food ha to purchase food instead
Tourism decreased due to loss of recreation in an oil spill area
All of these effects caused a long term clean up to fully repair most of the damages done by the spill
Factors affecting biodegration
Slow biodegration in the winter due to little bacteria growth
Other factors other than temp are soil moisture, pH, oxygen supply and nutrient availability
You can plant vegetation to help with the biodegration process
Storage of hazardous chemicals
Leave all products in organizational containers (secured lids) and labels
In a location out of reach from children
Store in cool, dry, ventilated places
Don’t store flammable substances in glass containers or substances such as gasoline should be stored outside of the house
Store different substances on separate shelves from each other
Discard of containers that are leaking or substances that are old
Dispersion
The scattering of a substance away from its source
Ex. If you spilled to much fertilizer on your lawn you could disperse it throughout the soil
Some substances that contaminate groundwater
Minerals in rocks and soil: iron, calcium
Organic substances ( natural or human made): pesticides, solvents
Leached from landfill sites: heavy metals (mercury)
Leak from underground storage or pipelines: gasoline, oil
Inorganic substances( industrial processes ect.): salt, fertilizers
Improper micro-organisms: bacteria, viruses
Household chemicals: detergents, nitrates
What dilutes or disperses a chemical quickly?
A fast flowing river or air mass
Dilution or dispersion combined with another clean-up process such as biodegration can be very effective
Crude oil spills
Exxon Valdez is a good example…
Occurred in prince William sound and changed the beauty of the lake
The small molecules oil spilled and dispersed into the air and water
Tar balls of heavy hydro garçons were washed ashore or sank into the sediment under the water
This is a long term problem and caused a major impact on the environment
Factors that affect the rate of groundwater
The soil had pores.. These pores are tiny spaces between soil grains that are sometimes tightly packed that the pores are not connected. In this case the water cannot flow through the soil as easily. If the pores are connected the soil is permeable and transports pollutants through the water more easily.
Transport in groundwater
Water that soaks into soil moves first into a zone near the surface where the soil grains contain both air and water (water table) Next it will move deeper and enters a zone where all the spaces are filled with water (groundwater)
Groundwater can move sideways, up and down
The water can exonerate concentrated with substances such as lead and creates problems to drink the water and use for other purposes
Impact of oil spills on plants and animals
Floating algae can be killed, invertebrates near shore could not survive due to decreased oxygen, loss of food and the toxic effect of hydrocarbons
Fish eggs and young fish were sensitive to the oil and died
Adult fish could escape by swimming away but the lost their habitat and good resources
Seabirds and mammals can become covered in oil so many of them would die as well
Biomagnification
Increase in concentration of a chemical or element as it moves up the food chain
Ex. Mercury: comes from emissions from coal-fires power plants ect. The mercury falls into fresh or salt water where bacteria join it to an organic molecule that alga can absorb
After this point mercury enters the good chain through the alga and leads to insects, green plants and fish. Eventually making it onto our plates and harming humans
Mercury contaminated water is a problem in Canada’s Great Lakes
Oil spill clean up
Booms am be used to clean up and obtain the spills in water
Ground spills occur too and have different procedures to clean up the spills
Crude oil
A mixture of many chemicals
Contains hundreds of different molecules in all shapes and sizes
Some in crude oil contain nitrogen, oxygen and sulfur
Crude oil cannot be used right when bit comes out from the ground.. It had to be refined through a process
Concentration of pollutants in the environment can be changed using different techniques such as..
Dispersion, dilution, biodegratuon, phytoremediation and photolysis
Hazardous chemicals include
Household cleaners Personal hygiene products Pet-care products Paint and paint products Pesticides and fertilizers Automotive fluids
New product regulations
Intended use, physical and chemical properties and active ingredient(s)
Instructions for use, safety precautions
Heal effects, environmental effects, toxicity to humans and first aid instructions in case of poisoning
Transportation of consumer goods
Should be placed in the trunk of a car where they will not fall over (secure)
Do not mix together hazardous household wastes when bringing to a collection site
Factors of the direction and distance of airborne pollutants
Pollutants properties, wind speed, and the direction of prevailing winds
Disposal if hazardous chemicals
Never pour wastes down the drain or into the soil
Do not throw them away in the garbage
If you do pour the substance down the drain it can enter into the sewage system it septic tanks and not be filtered, therefor they are entering into the surface water and harming the soil water, drinking water and even air
Aerobic and anaerobic biodegration
Aerobic: uses oxygen in the air to grow and produce bacteria for breakdown
Anaerobic: without oxygen in the air to thrive the breakdown with bacteria
Solid waste garbage
Some substances such as gasoline and oil can be recycled at a hazardous waste collection site
Take antifreeze to a recycling centre and don’t out it into the ground or drain where it will enter into your septic tank
Never place car batteries in a home garbage. They can be recycled
Take care or aresol cans, syringes, fertilizers, pesticides and paint products by putting them in a hazardous materials collection site
Transport in air
Release of the chemical at the source
Dispersion if chemical in the atmosphere
Deposition if the chemical in soil or water
The distribution of airborne pollutants may be limited by lack of wind, precipitation.
The pollutant will be depositors closer to its source if it is carried to the ground by rain or snow
It is hard to identify a pollutant that had travelled thousands of kilometres. Due to the movement of these chemicals it has become an international problem in which they are signing agreements to limit the amount of airborne pollutants.
Transport in the soil
Water landing on a field or your yard does four things:
Some evaporates
Some soaks into the soil and is taken by plants
Some runs into the street or stream
Some soaks though the soil, moves downwards, dissolves substances in the soil and carries them along
These substances are called leachate
Composition of soil can affect this: if packed closely- harder to leachate, if not packed- most likely to leachate compared to packed clay
Acids or other hazardous chemicals in the soil can neutralize organic substances such as broken down leaves that become organic material
Photolysis
The breakdown of compounds by sunlight. Some substances degrade from exposure to light
Ex. Photodegradable plastic: problem is that it will not break down if buried and out of sight from sunlight
Phytoremediation
Green plants can be used to remove or degrade hazardous materials
It reduces the concentration of harmful chemicals in the soul or groundwater
Plants can be used to clean up metals, hydrocarbons, solvents, pesticides, radioactive materials, explosives and landfill leachates
Dilution
Reduces the concentration of a pollutant by mixing the polluting substance with large quantities of air or water
Ex. If you drip some bleach into a sink of water it will dilute into the water and spread the molecules
Government regulations
Designed to protect consumers and reduce the risks of transporting,storing,using and disposing of hazardous materials
Hazardous waste collection sites
Found in almost all of Alberta communities
Wastes such as paints and fertilizers will be taken to theses sites for disposal
Materials that cannot be recycled will be safely packaged in large containers where they are sealed with later
Biodegration
Nature uses living things to clean up the environment
Organisms such as earthworms, bacteria and Fungi help the biodegration of most organic substances degrade
Algae live at the soil surface can use the broken down substance as organic compounds through photosynthesis for food
Carbon atoms in these molecules can be used to build compounds such as carbohydrates and protein
Transport in surface water
Potentially hazardous chemicals can enter the surface water from different sources such as air, groundwater, runoff from different sites, and the outflow from sewage treatment plants
These chemicals can be dispersed throughout the surface water by these sources becoming attached to solids and can build to in lakes or river bottoms, affecting organisms
We need to track and monitor the water continually due to this issue
Nitrogen oxides
Also air pollutants which form smog and acid rain
Like sulfur dioxide that affect our health by irritating the respiratory system and eyes
Formed mainly from the combustion in vehicles
Sulfur dioxide
Is an air pollutant that forms smog and acid rain
Can affect respiratory system and irritate eyes
Major source is industrial processes such as oil and gas industry, burning fuels such as coal, oil and natural gas
Combine with oxygen to form nitrogen which is harmful to plants, animals and non living objects (major air pollutants)
Pesticides have changed:
Because pesticides may be toxic scientists are designing new ones that last only one growing seasons and are broken down by bacteria
Some insects have become resistant to pesticides and build their generation to e resistant as well
Not all pesticides break down entirely in the environment, this causes the tissues of organisms to accumulate and cause serious health problems
Spring acid shock
The Canadian Shield has been affected by acid precipitation which causes acid deposition
In areas where acid precipitation is a problem it deposits into snow and ice in the winter. In the winter the snow and ice melt, therefor the water flows into streams and lakes… This is known as spring acid shock
Carbon monoxide
A colourless and odour less gas and is known as the silent killer
Main source is form human activity in noter vehicles
Other sources include: combustion of wood, natural gas, industrial processes, airplanes and forest fires
Dangerous because it reduces the amount of oxygen carried by the blood if inhaled and may result in headaches, sleepiness, chest pains, brain damage and even death
Microbiological indicators
Organisms such as bacteria cause serious health problems if they are present in large numbers
Samples of water are taken and tested for microorganisms… If the count is high the water requires additional treatment before it is considered for for humans
Not a good indicator of water quality:
Clarity is not a good indicator of water quality because clear water can sometimes be harmful to humans and other organisms
Ex: lakes affected by acid rain are crystal clear and lifeless
The ozone layer
Occurs in high in the earths atmosphere15-20 km above the surface
This ozone absorbs ultraviolet radiation which is a good thing
As the ozone layer became thinner over the years, more UV radiation is allowed to reach the earths surface, which is a bad thing. This can cause a harmful effect in organisms:
Increased risk if skin cancer in the cataracts in humans
Plankton in the sea are sensitive to UV radiation could die off of exposed to large amounts. This would affect all the animals that feed on plankton
Water quality is determined according to the 5 categories:
Human drinking water Recreation/swimming Livestock drinking water Irrigation Protection of aquatic life
Parts per trillion
(ppt) is difficult and requires special costly equipment
Only extremely hazardous substances are measured to this level of concentration
Aquatic environments
Diversity of all organisms decreases as acidity increases and dissolved oxygen decreases
If the pH in the water is below 5.0 there will not be many fish
Few insects and many worms may mean that the water contains little dissolved oxygen
