2.1:Monitoring Water Quality
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Transcript of 2.1:Monitoring Water Quality
2.1:Monitoring Water Quality
GO C2Identify processes for Measuring the Quantity of Different Substances in the Environment and for Monitoring air and water Quality.
Guided QuestionGuided Question
Why is it important to monitor the quality of water?
Would you Drink this water?
MonitoringMonitoring:: keeping track of something for keeping track of something for a specific purpose.a specific purpose.
Water quality is determined by what water is Water quality is determined by what water is used for. It is regulated by technicians used for. It is regulated by technicians
Their are five categories of water use:Their are five categories of water use:
1.1. Human drinking waterHuman drinking water2.2. Recreation such as swimmingRecreation such as swimming3.3. Livestock drinking waterLivestock drinking water4.4. IrrigationIrrigation5.5. Protection of aquatic lifeProtection of aquatic life
Biological IndicatorsBiological Indicators Scientist use organisms that live in the water to Scientist use organisms that live in the water to
help determine water quality. help determine water quality.
Microbiological IndicatorsMicrobiological Indicators Microscopic organisms such as bacteria can Microscopic organisms such as bacteria can
cause serious health problems if they are cause serious health problems if they are present in high enough numbers.( E coli present in high enough numbers.( E coli bacteria)bacteria)
Aquatic InvertebratesAquatic Invertebrates Invertebrates are animals Invertebrates are animals without backboneswithout backbones. .
They are used for monitoring because different They are used for monitoring because different invertebrates prefer different living conditions.invertebrates prefer different living conditions.
Examples of IndicatorsExamples of Indicators
Biological IndicatorsBiological Indicators Which organisms indicate a high level of dissolved OWhich organisms indicate a high level of dissolved O22? good water conditions ? good water conditions
Which organisms indicate a low level of dissolved OWhich organisms indicate a low level of dissolved O22? poor water conditions ? poor water conditions
Dissolved Dissolved Oxygen Oxygen
levellevel
ConsequencesConsequences
Dissolved Dissolved OO22
8 8 Excellent Excellent
Large variety of invertebrates (insect larvae, Large variety of invertebrates (insect larvae, beetles, worms) Many species of fish and other beetles, worms) Many species of fish and other desirable organismsdesirable organisms
Dissolved Dissolved OO22
6 Good6 Good
Few mayfly larvae, some stonefly larvae, some Few mayfly larvae, some stonefly larvae, some beetles, many midge larvae, many worms beetles, many midge larvae, many worms
including leechesincluding leeches Dissolved Dissolved
OO22
4 Low4 Low
Freshwater shrimp, many midge larvae, many Freshwater shrimp, many midge larvae, many worms including leeches. Some species have worms including leeches. Some species have difficulty living in critical levels. difficulty living in critical levels.
Dissolved Dissolved OO22
2 Very 2 Very LowLow
Many midge larvae, some worms including Many midge larvae, some worms including leeches leeches
Dissolved Dissolved OO22
0 Critical0 Critical
No species of game fish exist, some midge No species of game fish exist, some midge larvae, some worms larvae, some worms
Chemical Factors that Affect Chemical Factors that Affect OrganismsOrganisms
Water found in our environment may contain Water found in our environment may contain many different organic and inorganic compounds. many different organic and inorganic compounds. The concentration of these compounds affects The concentration of these compounds affects water quality. water quality.
The following are monitored as indicators of water The following are monitored as indicators of water quality:quality: Dissolved oxygenDissolved oxygen AcidityAcidity Heavy metalsHeavy metals Plant nutrientsPlant nutrients (such as nitrogen and phosphorus)(such as nitrogen and phosphorus) PesticidesPesticides SaltsSalts (such as sodium chloride and magnesium sulfate)(such as sodium chloride and magnesium sulfate)
Dissolved OxygenDissolved Oxygen
The level of dissolved oxygen The level of dissolved oxygen depends on:depends on: Temperature (due to change Temperature (due to change
in seasons)in seasons) Turbulence (due to wind or Turbulence (due to wind or
the speed of moving water)the speed of moving water) Photosynthesis of aquatic Photosynthesis of aquatic
plants or algaeplants or algae # of organisms using up the # of organisms using up the
oxygenoxygen
Dissolved oxygen is essential Dissolved oxygen is essential for the health of aquatic for the health of aquatic
life.life.
AcidityAcidity Precipitation with a pH lower than 5.6 is Precipitation with a pH lower than 5.6 is
considered considered acid rain/snowacid rain/snow. . Acid precipitation causes major problems in the Acid precipitation causes major problems in the
spring spring when the snow melts and flows into when the snow melts and flows into aquatic systems. aquatic systems. Spring acid shock Spring acid shock causes serious causes serious harm to the eggs and young offspring of fish.harm to the eggs and young offspring of fish.
As the acidity increases the diversity of organisms As the acidity increases the diversity of organisms decreases! decreases!
Most fish disappear if the water’s pH falls to 4.5.Most fish disappear if the water’s pH falls to 4.5.
Heavy MetalsHeavy Metals Heavy metals have a density of Heavy metals have a density of
5g/cm5g/cm33 or higher or higher Include copper, zinc, lead, mercury, Include copper, zinc, lead, mercury,
cadmium and nickelcadmium and nickel They naturally occur in rocks and soilThey naturally occur in rocks and soil They are mined to make: batteries, They are mined to make: batteries,
tires, paints, pipes, thermometers tires, paints, pipes, thermometers and fertilizersand fertilizers
Heavy metals must be monitored Heavy metals must be monitored because they can be toxic to a because they can be toxic to a variety of organismsvariety of organisms
Plant NutrientsPlant Nutrients (Phosphorus and Nitrogen Content)(Phosphorus and Nitrogen Content)
Phosphorus and nitrogen are Phosphorus and nitrogen are important for all living things, but too important for all living things, but too much can cause problems. Excess much can cause problems. Excess PP and and NN22 comes from: comes from: Sewage outfallsSewage outfalls Runoff from fertilized fieldsRunoff from fertilized fields
High amounts of P and NHigh amounts of P and N22 cause: cause:
Increased growth in algae and green plants Increased growth in algae and green plants
Plants dies and becomes food for bacteria Plants dies and becomes food for bacteria that decompose itthat decompose it
Bacteria increase in number Bacteria increase in number
Increased bacteria use up dissolved oxygen Increased bacteria use up dissolved oxygen
Fish and aquatic insects cannot survive Fish and aquatic insects cannot survive
PesticidesPesticides Some pesticides have long lasting effects as Some pesticides have long lasting effects as
they do not break down quickly and last in the they do not break down quickly and last in the environment for a long period of time ( DDT)environment for a long period of time ( DDT)
Most are now used for ONE growing seasonMost are now used for ONE growing season They do however create organisms that can They do however create organisms that can
become RESISTANT to the pesticidebecome RESISTANT to the pesticide Larger numbers of pesticides are creating Larger numbers of pesticides are creating
problems in the environment as if they are problems in the environment as if they are mixed together they create a TOXIC mixed together they create a TOXIC substancesubstance
TOXICITY – describes how poisonous a TOXICITY – describes how poisonous a substance is substance is
Measuring ToxicityMeasuring Toxicity Toxins or poisons are substances that Toxins or poisons are substances that
produce serious health problems or death produce serious health problems or death when introduced into an organism. when introduced into an organism.
In order to compare toxins, a measurement In order to compare toxins, a measurement called called LD50LD50 is used. is used.
LDLD stands for stands for lethal doselethal dose; ; 5050 represents represents 50%50%..
LD50 is the LD50 is the amount of a substance that amount of a substance that causes 50% of animals to die if they are given causes 50% of animals to die if they are given a specified dose of the substance all at once.a specified dose of the substance all at once.
Table salt – 3000mg/kg, Caffeine – 192 mg/kg, Table salt – 3000mg/kg, Caffeine – 192 mg/kg, DDT 87mg/kg (all given to rats by mouth)DDT 87mg/kg (all given to rats by mouth)
Measuring Chemicals in the Measuring Chemicals in the EnvironmentEnvironment
The concentration of chemicals in the The concentration of chemicals in the environment is usually measured in environment is usually measured in parts per million (ppm)parts per million (ppm)
One part per million means that one One part per million means that one unit of an element can be found in unit of an element can be found in one million units of solutionone million units of solution
Some times the concentrations are Some times the concentrations are expressed in expressed in parts per billion parts per billion (ppb)(ppb) or or parts per trillion (ppt)parts per trillion (ppt)
1 ppm1 ppm is about the same as 1 drop of is about the same as 1 drop of food colouring in a half filled bath tubfood colouring in a half filled bath tub
1 ppb1 ppb is about the same as 1 drop of is about the same as 1 drop of food colouring in a swimming poolfood colouring in a swimming pool
1 ppt1 ppt is about the same as 1 drop of is about the same as 1 drop of food colouring in 1000 swimming food colouring in 1000 swimming poolspools
Determining ppmDetermining ppm
ppm= ppm= Part (g or mL) Part (g or mL) ie. 1 Part per ie. 1 Part per million million 1 000 000 mL 1 000 000 mL millilitresmillilitres
ppm =ppm = mg mg = = mg mg = = g or mL _ g or mL _
L 1 000mL 1 000 000mL L 1 000mL 1 000 000mL
ExampleExample
If there are 20 mg of oxygen If there are 20 mg of oxygen dissolved in 5 L of water, how many dissolved in 5 L of water, how many ppm of dissolved oxygen is there?ppm of dissolved oxygen is there?
ppm = ppm = 20 mg 20 mg = 4 mg/L = 4 ppm= 4 mg/L = 4 ppm
5 L5 L
Example 2Example 2 If there is 5mL of oxygen dissolved in If there is 5mL of oxygen dissolved in
995 mL of water, how many ppm of 995 mL of water, how many ppm of dissolved oxygen is there?dissolved oxygen is there?
ppm = ppm = g or mL _ g or mL _
1 000 000mL 1 000 000mL
ppm = ppm = 5 mL 5 mL = 0.005 mL/mL = 0.005 mL/mL
1000mL1000mL
ppm = ppm = 0.0050.005 = 5000 ppm = 5000 ppm
10001000
Water Quality – Hot Water Quality – Hot TopicTopic
http://www.youtube.com/watch?v=2igTexiW3bg
Do you think it will be banned?Do you think it will be banned? Do you think it Do you think it should should be?be? Could it be a risk to humans?Could it be a risk to humans? Should it be used, even if not a risk Should it be used, even if not a risk
to human?to human? Homework: can you find any Homework: can you find any
triclosan in your home?triclosan in your home?