11-01: Humans and Our Environment
Invention of the steam whistle
Boom in industry
Beginning of all environmental issues today
Our population is growing (about 7 billion people now)
With abundant resources populations of living things tend to increase exponentially
The carrying capacity for humans has been drastically increased by technologies
Carrying capacity: particular ecosystems have certain numbers of resources, and in order to support life, everything needs sufficient resources to survive.
Because of advantages in medicine, food growth, technology, etc, we have the ability to live longer
Our large population has a large impact on the environments we inhabit
Technology has helped us live longer and helped the population grow at an incredibly fast rate
Shared resources are often collectively over used by many individuals and under maintained often depleting or spoiling the resource
“It's just one _____” attitude adds up. As individuals, out actions have an almost insignificant impact on the environment
As a population the effects are massive and affect us all
Everyone needs to do their part, every action does make an impact (whether that action be bad, good, or neutral)
Coal, oil, and natural gas extraction take a heavy toll on ecosystems
Dams for hydroelectric power can devastate the environment they are in too
Limited landfill space
Eventually these will fill up- Increasing quantities of hazardous wastes, Single use plastics are major contributors
Pesticide and fertilizer use
Soil degradation
If not used carefully, all of these resources will used up
Monocrop farming: growing one plant at a time
Sustainable farming: rotate crops and let the land “rest”
An issue because we have the technology now to assess demand and to choose what to plant based on what will make the most money
All of the resources used to grow that such a plant will be used up and in the long run it will harm the environment devestatingly
Fishing practices aren't always regulated properly
If we catch too many fish too quickly, the fish population will dwindle and won't reproduce properly
We don't know what will happen when things go extinct
A balanced ecosystem requires equal amounts of predators and prey, as well as balanced resources
Ultimately does impact humans and their comfort Species may not be able to survive in changing conditions because of deforestation Habitat and species loss We lose populations due to changing conditions’ Invasive species Habitat fragmentation
Pollution: when a human activity causes the release of a substance that harms the environment
Pollutant: waste material from human activity that can cause harm to an ecosystem
Environmental contaminants: are substances that can harm humans and other living things
Pollutants and contaminants are types of environmental factors that affect our environment and both living and non living things
5 major gases considered to be air pollutants produced by human activities
Toxic: removes oxygen from airways, suffocates humans by preventing them from breathing in oxygen
A clear colourless odourless gas
We get it from the partial burning of organic matter like gas, coal and wood
Released from car exhausts and cigarettes
One of the contributors that causes acid rain
Smells like rotten eggs
Produced by burning sulphur containing fuels
Nitrogen is the most abundant element (air has ~78% nitrogen)
One of the contributing factors to acid rain
Everything has a pH that tells us how acid or basic something is, rain water has a certain level of acidity and when exposed to certain things, its PH changes and thus it becomes acidic and then changes the nature of the soil (and plants have a low tolerance for acidity)
Produced by burning fossil fuels
Tiny particles in the air that shouldn't be there, hard to filter out
Range of particles that includes ash from factories, smoke from fires, soil and fertiliser from farming. Pollen, dust and mould are natural particulates
Particulates can cause a range of health problems for humans
E.g. the people who helped clean up 911 dealt with this
Dust particles are less than 10 microns
Hydrocarbons come from fuels that can evaporate into the air
From the air, they can react with nitrogen oxides in the presence of sunlight to produce photochemical smog, in particular, it's the nitrogen oxides
Smoke + Fog = Smog
The mix of compounds in smog can damage plants and injure lungs
Nitrogen dioxide is in the air, Nitrogen oxides are formed when solar energy hits, and it mixes with water, when that mixture mixes with other chemicals, then they are left to be in the air
Comes from refrigerators, aerosol cans, air conditioners,
Causes ozone in the upper atmosphere to break down - this allows for more UV light to reach Earth and cause issues (e.g. skin cancer)
Ozone layer: protective layer blocking harmful rays from the planet
Ozone layer is thinning out
work
Workplace chemicals such as herbicides, solvents and volatile organic compounds (VOCs) can also harm humans in an indoor or outdoor environment
VOCs have been often used in paints
WHMIS symbols warn of dangers
Pathogens: harmful to humans (i.e. disease) that is transmitted from person to person (organic)
COVID is a pathogen
Disease causing bacteria, viruses, single celled organisms and fungi can be transmitted through air, food or water
Animals can also carry pathogens such as West Nile virus (bitten by a mosquito) and Lyme disease (bitten by a tick)
E.g.: Salmonella, E. Coli, etc.
Environmental contaminants can enter the body in many ways
We can inhale it, it can be absorbed, we can eat it (ingestion), or it can be injected
Your respiratory system ends with alveoli which can absorb inhaled contaminants
Body secretes mucus and has cilia (hairs and little flaps of skin that are hair-like) to trap small amounts of many particles (e.g. bacteria, dust)
We have no defence for pollutants like VOCs and pesticides
Respiratory System Harm
Contaminant | Reaction | Diseases |
---|---|---|
Smoke, particulates, smog, CO, SO2, VOCs | Eyes, nose, throat irritation, headache | Inflammation |
Smoke, particulates, smog, CO, SO2, VOCs, pathogens | Difficulty breathing, wheezing, coughing, excess mucous | Asthma, bronchitis, emphysema |
Smoke, particulates, hydrocarbons, pathogens | Inflamed lungs, dry cough | Pneumonia |
Smoke, ionising radiation, hydrocarbons, workplace chemicals, arsenic, asbestos | Chronic cough, difficulty breathing, bloody mucus | Lung cancer |
Ingest: to eat, comes down to your digestive system
Ingested contaminants can be absorbed by the digestive system
Body defences include vomiting and blood filtration by the liver
When you ingest contaminants, you may vomit because the body wants to purge itself of the contaminants
Digestive System Harm
Contaminant | Reaction | Disease |
---|---|---|
Pathogens | Intestinal pain, vomiting, cramps | Cholera, giardia, dysentery |
Alcohol, drugs | Nausea, fatigue, weight loss | Cirrhosis (liver starts to break down) |
Listeria monocytogenes | Fever, rash, nausea, headache, shock | Listeriosis |
Escherishia Coli (E. Coli) | Fever, chills, pain | Septicemia |
Workplace chemicals, drugs | Vomiting, diarrhea, trouble breathing | Heavy metal poisoning |
Alcohol, workplace chemicals, smoking | Weakness, weight loss, back pain, clay coloured stool | Cancer of esophagus, pancreas, etc. (smoking can cause many kinds of cancer) |
Skin is the first line of defence for our bodies. It contains protective layers but also capillaries that can absorb contaminants
Skin is the largest organ and it is a layer of protection for our bodies
Oils, tar, cleaning products, and pesticides can all enter this way
Pathogens like the West Nile Virus can enter skin by injection
Outer layer, inner layer, subcutaneous layer
Once the skin is breached, it can get anywhere in the body because it enters the bloodstream
Rashes, hives, itching, hair loss, burns, and skin cancer can come from exposure to environmental factors such as cleaning fluids, workplace chemicals, drugs, and radiation
Workplace chemicals and pathogens like parasites can cause harm to your circulatory and lymphatic system
Lymph is fluid found in spaces between cells. Bacteria and wastes are filtered out at lymph nodes and by spleen
Pesticides, workplace chemicals, antiseptics, bacteria and viruses, etc. can cause damage to brain, spine, and nerves
Sperm, eggs, and sex organs can be damaged or result in cancers caused by environmental contaminants as well
Meningitis: inside the brain there is an area called the meninges. There are no sensors on the brain for touch, but if a bacteria gets there then it can become swelled and eventually may lead to death
Measles is a childhood infection caused by a virus pathogen that lives in the mucus of the nose and throat
It is very contagious - even before symptoms like the rash show up
Measles infections afflict 20 million people every year and results in 100 000 deaths per year
Symptoms: runny nose, cough, tiredness, loss of appetite, fever, sensitivity to light, spots all over the body and inside mouth, conjunctivitis (pink eye)
Vaccines can protect humans from many pathogens like the measles
They work by exposing your body to weakened forms of a microbe so that the body can learn to fight off an infection
White blood cells or antibodies (soldiers) learn to fight this
Antibodies are very specific
If a certain number of people are vaccinated against a disease then the whole group becomes less likely to get it
This is called herd immunity
Recent anti-vaxx movements have endangered many lives unnecessarily
They claim that they can cause Autism and other negative effects
Anti mask rallies and protests
“This years flu strain is 65% effective” → means that you are either 100% or 0% protected, certain people will be protected and others will not - on average 65/100 will be protected and the other 35 will not be
Asthma reactions triggered by environment can be treated with medication
Antimalarial medications can kill the parasites that can cause malaria to protect a person from the disease
No medication or vaccine is 100% effective
Sunscreen and UV protective clothing can protect humans from UV light that can burn skin - the sun protection factor (SPF) tells you how effective it is
Pollutants on the air can be removed by air purifying respirators
Really toxic environments may need a supplied air respirator
After 911, people tried to clean up the rubble without protection and they are sick because of what they inhaled
The most effective way to prevent the spread of disease is to wash your hands
No need to buy a special antibiotic soap
Soap forms a reaction with certain particles and so when you wash away the soap you wash away the new compound (thus washing away the bacteria and other icky things on your hands)
Every year ~12 million Canadians get a food borne illness such as botulism which is caused by a bacterium that can live in improperly preserved food
Food poisoning - eating food that hasn't been prepared properly will make you sick
Very important to know how to handle things
Step 1: clean - protects by getting rid of any bacteria that could be harbored on your fingers
Step 2: separate raw meat from other food when preparing it - don't eat meat raw
Step 3: cook your food - don't eat anything that you shouldn't at a level of underpreparedness
Step 4: chill your food - bacteria cannot thrive when it's too cold and it will slow down their growth - the colder it is, the slower bacteria growth
If you cook it for a certain amount of time over a certain amount of heat then this will also keep your food safe as most bacteria can't exist over a certain temperature
Canadians spend ~ 90% of time indoors
Smoke: fireplaces, wood burning stoves, cigarettes, etc. all release particulate matter
Poor circulation: airtight homes, dirty air in HVAC systems, attics, basements, etc. all remain in the home
Toiletries: aerosols, lotions, vinyl shower curtains, airborne chemicals
Mold: bathrooms and kitchens, always test
Cooking: high level of particles
Candles and electronics: release toxins that can lead to headache, fatigue, etc
Cleaners and detergents: VOCs
VOCs: toxic vapours that are gassed off of manmade materials (e.g. furniture, bedding, carpets)
Certain homes have filters to combat this
The use of fossil fuels since the industrial revolution have massively increased the amount of CO2 and other GHG emissions into the environment
Deforestation also increases the amount of carbon as trees are carbon sinks
Primary carbon footprint measures GHG emissions from burning fuels for energy and transportation
Secondary carbon footprint measures GHGs from food, products, and services you buy
Everything has a carbon price tag
Some countries produce more GHG than others
Effects of climate change including fires, drought, and extreme weather often affect poorer people and countries more than wealthier people and countries
Humans spill oil in marine ecosystems which can be devastating
Oil spills on land can also end up in freshwater ecosystems like lakes, rivers, and wetlands
Less dense parts of oil float and form a thin layer called a slick
More dense parts of oil sink and form tar balls that can wash ashore long after a spill
Use kerosene to get the oil spills off you when swimming
Seagrass and kelp can be covered and killed by oil
Animals that depend on these plants for food and shelter also die
Animals can be smothered by oil or be poisoned by ingesting it
Oil also mats down fur and feathers of mammals and birds which can cause the to freeze to death and reduce their ability to swim, float, or fly
Humans produce massive amounts of gasses that make acid rain or snow
Acid precipitation can be episodic or chronic
Snowmelt vs. Water bodies that are permanently acidic
We pump in gasses like sulfur dioxide and nitrogen oxides
Chronic: always precipitation is acidic
Epositic: something precipitation is acidic
If it falls down as snow, the snow will melt and then run off, some changes are more permanent (e.g. if the water is completely acidic then it will have drastic impacts)
Reduces basic nutrients such as calcium and magnesium from soil by leaching
Loss of these nutrients slows down plant growth and makes them more vulnerable to insects, diseases and drought
Increases levels of heavy metals in soils such as aluminum; these metals can be toxic to fish, plants, birds, and other animals
Rocks in many Ontario ecosystems can not neutralize the acid and can result in dead lakes like in Killarney
Native species are adapted to live in the climate, soil, water and with the other creatures found naturally in their habitat
Non native species are introduced by humans into new habitats where they are normally not found. This happens due to travel, agriculture, perts, live bait use, etc.
Invasive species are non native species that harm native species by competing with them for resources, they may also lack predators and their population can grow quickly
E.g. purple loosestrife: In the early 1800’s people brought it over from Europe for its pretty flowers and medicinal uses. Here it has taken over many wetlands and outcompetes other plants like milkweed and cat tails which also impacts the animals that would eat them for food!
In order for us to address environmental issues scientifically, we need info
Soil, water, & air can be sampled and monitored over time to determine if changes are happening
Soil core sample is a common way to measure the quality of soil to be used for agriculture
Soil exists in layers called horizons
At a lab, the technicians will measure components such as phosphorus, potassium, magnesium and nitrogen
Water is also sampled at different depths to monitor the amount and location of different pollutants
Drinking water is also sampled constantly by towns and cities
Microbiological tests: bacteria or coliforms are living things that could be harmful to humans
Chemical tests: chemicals like nitrates or lead might indicate contamination from sewage or rusty leaking pipes
Radiological tests: some places have natural levels of uranium that must be monitored
We have a certain amount of radiation that were exposed to daily - the level must be considered
Industrial plants often release exhaust from smokestacks that are monitored for emissions of sulfur, mercury, and carbon
Particulate matter is also closely monitored because of its effects on human health
In ontario, the AQI provides information about levels of smog in the air
Air monitoring stations throughout the province provide data on 6 key air pollutants, and meteorologists update the AQI hourly
If the AQI gets really bad they will issue a smog alert to the public
Places where ice has been accumulating for thousands of years can provide air and water samples about conditions in the past
Plant pollen shows species that were alive
Ice crystal shape is related to temperature and humidity
Air bubbles show levels of oxygen and CO2
Biodiversity can be measured by counting the number of each species found in a square of a given size
Measures how well things are growing in a given area
This is a study done before a project that may affect the environment
Factors include whether the project may impact aquatic species, migrating birds, Indigenous uses
Isolated island alone in the pacific ocean
Natives cut down palm trees to build canoes & monuments to their gods
New palms couldn't grow due to rats
Eventually, the last palm was cut and the population collapsed
Often viewed as a cautionary tale for us on this little earth on vast space
Consequence when nations are not sustainable
Just like in Rapa Nui we must understand the problems we have
We have a variety of growing environmental problems that could drastically affect our way of life if not dealt with effectively
Informed citizens can act to make changes that will address these problems in a scientific way
All claims about environmental issues start with evidence
Monitoring levels of pollutants/number of species in a given area will show changes over time that can inform our decisions
We don't know what progress could stem from having these animals go extinct
Predictions can be made about the future using theories about how the world works
New theories displace older ones when new evidence is found
Compute models use theories to make long term predictions about complex data
E.g. geocentric VS. heliocentric ways of thinking
Science can be used to prove a theory wrong
In order to motivate and change people’s mindsets - we need to get people to think differently
Many cultures act as if infinite development as growth is their goal/that humans are separate and above their environment
The traditional Indigenous paradigm of connectedness of all things and sustainability is different
Current sustainability model: economy, people and nature are separate and dealt with differently
Other ideas view nature as most important - e.g. Indigenous POV’s
Most business models and governments have a very short term view
How do I make money now? How do I get elected now?
A longer term view is needed for long term survival & sustainability
The skills that we should be developing from school
To solve environmental problems, we must be critical thinker who can seek new facts, learn new skills, form new ideas to test
Reasoning
Evaluation
Problem solving
Cycle of critical thinking
Critical thinkers have produced new technologies that can help with many environmental problems
Renewable energy
Only works in some conditions
Must be able to store energy for when it can't collect the energy
Takes up a lot of space
Solar panels
Taking food scraps and isolating them - composting
Composting: organic material decomposes and forms soil that can be used - the nutrients are recycled
Not everything put in the “blue bin” is recycled - only about 30-40% (e.g. bottles, bags, etc.)
Ozone depletion in the upper atmosphere was detected by satellite technology
Aerosol CFCs were banned in 1987 when it was determined that they were causing the loss
Since then, the ozone levels have increased and continue to improve
Freeon used to release CFC, it worked well at cooling things down (e.g. fridges, coolers, AC)
Invention of the steam whistle
Boom in industry
Beginning of all environmental issues today
Our population is growing (about 7 billion people now)
With abundant resources populations of living things tend to increase exponentially
The carrying capacity for humans has been drastically increased by technologies
Carrying capacity: particular ecosystems have certain numbers of resources, and in order to support life, everything needs sufficient resources to survive.
Because of advantages in medicine, food growth, technology, etc, we have the ability to live longer
Our large population has a large impact on the environments we inhabit
Technology has helped us live longer and helped the population grow at an incredibly fast rate
Shared resources are often collectively over used by many individuals and under maintained often depleting or spoiling the resource
“It's just one _____” attitude adds up. As individuals, out actions have an almost insignificant impact on the environment
As a population the effects are massive and affect us all
Everyone needs to do their part, every action does make an impact (whether that action be bad, good, or neutral)
Coal, oil, and natural gas extraction take a heavy toll on ecosystems
Dams for hydroelectric power can devastate the environment they are in too
Limited landfill space
Eventually these will fill up- Increasing quantities of hazardous wastes, Single use plastics are major contributors
Pesticide and fertilizer use
Soil degradation
If not used carefully, all of these resources will used up
Monocrop farming: growing one plant at a time
Sustainable farming: rotate crops and let the land “rest”
An issue because we have the technology now to assess demand and to choose what to plant based on what will make the most money
All of the resources used to grow that such a plant will be used up and in the long run it will harm the environment devestatingly
Fishing practices aren't always regulated properly
If we catch too many fish too quickly, the fish population will dwindle and won't reproduce properly
We don't know what will happen when things go extinct
A balanced ecosystem requires equal amounts of predators and prey, as well as balanced resources
Ultimately does impact humans and their comfort Species may not be able to survive in changing conditions because of deforestation Habitat and species loss We lose populations due to changing conditions’ Invasive species Habitat fragmentation
Pollution: when a human activity causes the release of a substance that harms the environment
Pollutant: waste material from human activity that can cause harm to an ecosystem
Environmental contaminants: are substances that can harm humans and other living things
Pollutants and contaminants are types of environmental factors that affect our environment and both living and non living things
5 major gases considered to be air pollutants produced by human activities
Toxic: removes oxygen from airways, suffocates humans by preventing them from breathing in oxygen
A clear colourless odourless gas
We get it from the partial burning of organic matter like gas, coal and wood
Released from car exhausts and cigarettes
One of the contributors that causes acid rain
Smells like rotten eggs
Produced by burning sulphur containing fuels
Nitrogen is the most abundant element (air has ~78% nitrogen)
One of the contributing factors to acid rain
Everything has a pH that tells us how acid or basic something is, rain water has a certain level of acidity and when exposed to certain things, its PH changes and thus it becomes acidic and then changes the nature of the soil (and plants have a low tolerance for acidity)
Produced by burning fossil fuels
Tiny particles in the air that shouldn't be there, hard to filter out
Range of particles that includes ash from factories, smoke from fires, soil and fertiliser from farming. Pollen, dust and mould are natural particulates
Particulates can cause a range of health problems for humans
E.g. the people who helped clean up 911 dealt with this
Dust particles are less than 10 microns
Hydrocarbons come from fuels that can evaporate into the air
From the air, they can react with nitrogen oxides in the presence of sunlight to produce photochemical smog, in particular, it's the nitrogen oxides
Smoke + Fog = Smog
The mix of compounds in smog can damage plants and injure lungs
Nitrogen dioxide is in the air, Nitrogen oxides are formed when solar energy hits, and it mixes with water, when that mixture mixes with other chemicals, then they are left to be in the air
Comes from refrigerators, aerosol cans, air conditioners,
Causes ozone in the upper atmosphere to break down - this allows for more UV light to reach Earth and cause issues (e.g. skin cancer)
Ozone layer: protective layer blocking harmful rays from the planet
Ozone layer is thinning out
work
Workplace chemicals such as herbicides, solvents and volatile organic compounds (VOCs) can also harm humans in an indoor or outdoor environment
VOCs have been often used in paints
WHMIS symbols warn of dangers
Pathogens: harmful to humans (i.e. disease) that is transmitted from person to person (organic)
COVID is a pathogen
Disease causing bacteria, viruses, single celled organisms and fungi can be transmitted through air, food or water
Animals can also carry pathogens such as West Nile virus (bitten by a mosquito) and Lyme disease (bitten by a tick)
E.g.: Salmonella, E. Coli, etc.
Environmental contaminants can enter the body in many ways
We can inhale it, it can be absorbed, we can eat it (ingestion), or it can be injected
Your respiratory system ends with alveoli which can absorb inhaled contaminants
Body secretes mucus and has cilia (hairs and little flaps of skin that are hair-like) to trap small amounts of many particles (e.g. bacteria, dust)
We have no defence for pollutants like VOCs and pesticides
Respiratory System Harm
Contaminant | Reaction | Diseases |
---|---|---|
Smoke, particulates, smog, CO, SO2, VOCs | Eyes, nose, throat irritation, headache | Inflammation |
Smoke, particulates, smog, CO, SO2, VOCs, pathogens | Difficulty breathing, wheezing, coughing, excess mucous | Asthma, bronchitis, emphysema |
Smoke, particulates, hydrocarbons, pathogens | Inflamed lungs, dry cough | Pneumonia |
Smoke, ionising radiation, hydrocarbons, workplace chemicals, arsenic, asbestos | Chronic cough, difficulty breathing, bloody mucus | Lung cancer |
Ingest: to eat, comes down to your digestive system
Ingested contaminants can be absorbed by the digestive system
Body defences include vomiting and blood filtration by the liver
When you ingest contaminants, you may vomit because the body wants to purge itself of the contaminants
Digestive System Harm
Contaminant | Reaction | Disease |
---|---|---|
Pathogens | Intestinal pain, vomiting, cramps | Cholera, giardia, dysentery |
Alcohol, drugs | Nausea, fatigue, weight loss | Cirrhosis (liver starts to break down) |
Listeria monocytogenes | Fever, rash, nausea, headache, shock | Listeriosis |
Escherishia Coli (E. Coli) | Fever, chills, pain | Septicemia |
Workplace chemicals, drugs | Vomiting, diarrhea, trouble breathing | Heavy metal poisoning |
Alcohol, workplace chemicals, smoking | Weakness, weight loss, back pain, clay coloured stool | Cancer of esophagus, pancreas, etc. (smoking can cause many kinds of cancer) |
Skin is the first line of defence for our bodies. It contains protective layers but also capillaries that can absorb contaminants
Skin is the largest organ and it is a layer of protection for our bodies
Oils, tar, cleaning products, and pesticides can all enter this way
Pathogens like the West Nile Virus can enter skin by injection
Outer layer, inner layer, subcutaneous layer
Once the skin is breached, it can get anywhere in the body because it enters the bloodstream
Rashes, hives, itching, hair loss, burns, and skin cancer can come from exposure to environmental factors such as cleaning fluids, workplace chemicals, drugs, and radiation
Workplace chemicals and pathogens like parasites can cause harm to your circulatory and lymphatic system
Lymph is fluid found in spaces between cells. Bacteria and wastes are filtered out at lymph nodes and by spleen
Pesticides, workplace chemicals, antiseptics, bacteria and viruses, etc. can cause damage to brain, spine, and nerves
Sperm, eggs, and sex organs can be damaged or result in cancers caused by environmental contaminants as well
Meningitis: inside the brain there is an area called the meninges. There are no sensors on the brain for touch, but if a bacteria gets there then it can become swelled and eventually may lead to death
Measles is a childhood infection caused by a virus pathogen that lives in the mucus of the nose and throat
It is very contagious - even before symptoms like the rash show up
Measles infections afflict 20 million people every year and results in 100 000 deaths per year
Symptoms: runny nose, cough, tiredness, loss of appetite, fever, sensitivity to light, spots all over the body and inside mouth, conjunctivitis (pink eye)
Vaccines can protect humans from many pathogens like the measles
They work by exposing your body to weakened forms of a microbe so that the body can learn to fight off an infection
White blood cells or antibodies (soldiers) learn to fight this
Antibodies are very specific
If a certain number of people are vaccinated against a disease then the whole group becomes less likely to get it
This is called herd immunity
Recent anti-vaxx movements have endangered many lives unnecessarily
They claim that they can cause Autism and other negative effects
Anti mask rallies and protests
“This years flu strain is 65% effective” → means that you are either 100% or 0% protected, certain people will be protected and others will not - on average 65/100 will be protected and the other 35 will not be
Asthma reactions triggered by environment can be treated with medication
Antimalarial medications can kill the parasites that can cause malaria to protect a person from the disease
No medication or vaccine is 100% effective
Sunscreen and UV protective clothing can protect humans from UV light that can burn skin - the sun protection factor (SPF) tells you how effective it is
Pollutants on the air can be removed by air purifying respirators
Really toxic environments may need a supplied air respirator
After 911, people tried to clean up the rubble without protection and they are sick because of what they inhaled
The most effective way to prevent the spread of disease is to wash your hands
No need to buy a special antibiotic soap
Soap forms a reaction with certain particles and so when you wash away the soap you wash away the new compound (thus washing away the bacteria and other icky things on your hands)
Every year ~12 million Canadians get a food borne illness such as botulism which is caused by a bacterium that can live in improperly preserved food
Food poisoning - eating food that hasn't been prepared properly will make you sick
Very important to know how to handle things
Step 1: clean - protects by getting rid of any bacteria that could be harbored on your fingers
Step 2: separate raw meat from other food when preparing it - don't eat meat raw
Step 3: cook your food - don't eat anything that you shouldn't at a level of underpreparedness
Step 4: chill your food - bacteria cannot thrive when it's too cold and it will slow down their growth - the colder it is, the slower bacteria growth
If you cook it for a certain amount of time over a certain amount of heat then this will also keep your food safe as most bacteria can't exist over a certain temperature
Canadians spend ~ 90% of time indoors
Smoke: fireplaces, wood burning stoves, cigarettes, etc. all release particulate matter
Poor circulation: airtight homes, dirty air in HVAC systems, attics, basements, etc. all remain in the home
Toiletries: aerosols, lotions, vinyl shower curtains, airborne chemicals
Mold: bathrooms and kitchens, always test
Cooking: high level of particles
Candles and electronics: release toxins that can lead to headache, fatigue, etc
Cleaners and detergents: VOCs
VOCs: toxic vapours that are gassed off of manmade materials (e.g. furniture, bedding, carpets)
Certain homes have filters to combat this
The use of fossil fuels since the industrial revolution have massively increased the amount of CO2 and other GHG emissions into the environment
Deforestation also increases the amount of carbon as trees are carbon sinks
Primary carbon footprint measures GHG emissions from burning fuels for energy and transportation
Secondary carbon footprint measures GHGs from food, products, and services you buy
Everything has a carbon price tag
Some countries produce more GHG than others
Effects of climate change including fires, drought, and extreme weather often affect poorer people and countries more than wealthier people and countries
Humans spill oil in marine ecosystems which can be devastating
Oil spills on land can also end up in freshwater ecosystems like lakes, rivers, and wetlands
Less dense parts of oil float and form a thin layer called a slick
More dense parts of oil sink and form tar balls that can wash ashore long after a spill
Use kerosene to get the oil spills off you when swimming
Seagrass and kelp can be covered and killed by oil
Animals that depend on these plants for food and shelter also die
Animals can be smothered by oil or be poisoned by ingesting it
Oil also mats down fur and feathers of mammals and birds which can cause the to freeze to death and reduce their ability to swim, float, or fly
Humans produce massive amounts of gasses that make acid rain or snow
Acid precipitation can be episodic or chronic
Snowmelt vs. Water bodies that are permanently acidic
We pump in gasses like sulfur dioxide and nitrogen oxides
Chronic: always precipitation is acidic
Epositic: something precipitation is acidic
If it falls down as snow, the snow will melt and then run off, some changes are more permanent (e.g. if the water is completely acidic then it will have drastic impacts)
Reduces basic nutrients such as calcium and magnesium from soil by leaching
Loss of these nutrients slows down plant growth and makes them more vulnerable to insects, diseases and drought
Increases levels of heavy metals in soils such as aluminum; these metals can be toxic to fish, plants, birds, and other animals
Rocks in many Ontario ecosystems can not neutralize the acid and can result in dead lakes like in Killarney
Native species are adapted to live in the climate, soil, water and with the other creatures found naturally in their habitat
Non native species are introduced by humans into new habitats where they are normally not found. This happens due to travel, agriculture, perts, live bait use, etc.
Invasive species are non native species that harm native species by competing with them for resources, they may also lack predators and their population can grow quickly
E.g. purple loosestrife: In the early 1800’s people brought it over from Europe for its pretty flowers and medicinal uses. Here it has taken over many wetlands and outcompetes other plants like milkweed and cat tails which also impacts the animals that would eat them for food!
In order for us to address environmental issues scientifically, we need info
Soil, water, & air can be sampled and monitored over time to determine if changes are happening
Soil core sample is a common way to measure the quality of soil to be used for agriculture
Soil exists in layers called horizons
At a lab, the technicians will measure components such as phosphorus, potassium, magnesium and nitrogen
Water is also sampled at different depths to monitor the amount and location of different pollutants
Drinking water is also sampled constantly by towns and cities
Microbiological tests: bacteria or coliforms are living things that could be harmful to humans
Chemical tests: chemicals like nitrates or lead might indicate contamination from sewage or rusty leaking pipes
Radiological tests: some places have natural levels of uranium that must be monitored
We have a certain amount of radiation that were exposed to daily - the level must be considered
Industrial plants often release exhaust from smokestacks that are monitored for emissions of sulfur, mercury, and carbon
Particulate matter is also closely monitored because of its effects on human health
In ontario, the AQI provides information about levels of smog in the air
Air monitoring stations throughout the province provide data on 6 key air pollutants, and meteorologists update the AQI hourly
If the AQI gets really bad they will issue a smog alert to the public
Places where ice has been accumulating for thousands of years can provide air and water samples about conditions in the past
Plant pollen shows species that were alive
Ice crystal shape is related to temperature and humidity
Air bubbles show levels of oxygen and CO2
Biodiversity can be measured by counting the number of each species found in a square of a given size
Measures how well things are growing in a given area
This is a study done before a project that may affect the environment
Factors include whether the project may impact aquatic species, migrating birds, Indigenous uses
Isolated island alone in the pacific ocean
Natives cut down palm trees to build canoes & monuments to their gods
New palms couldn't grow due to rats
Eventually, the last palm was cut and the population collapsed
Often viewed as a cautionary tale for us on this little earth on vast space
Consequence when nations are not sustainable
Just like in Rapa Nui we must understand the problems we have
We have a variety of growing environmental problems that could drastically affect our way of life if not dealt with effectively
Informed citizens can act to make changes that will address these problems in a scientific way
All claims about environmental issues start with evidence
Monitoring levels of pollutants/number of species in a given area will show changes over time that can inform our decisions
We don't know what progress could stem from having these animals go extinct
Predictions can be made about the future using theories about how the world works
New theories displace older ones when new evidence is found
Compute models use theories to make long term predictions about complex data
E.g. geocentric VS. heliocentric ways of thinking
Science can be used to prove a theory wrong
In order to motivate and change people’s mindsets - we need to get people to think differently
Many cultures act as if infinite development as growth is their goal/that humans are separate and above their environment
The traditional Indigenous paradigm of connectedness of all things and sustainability is different
Current sustainability model: economy, people and nature are separate and dealt with differently
Other ideas view nature as most important - e.g. Indigenous POV’s
Most business models and governments have a very short term view
How do I make money now? How do I get elected now?
A longer term view is needed for long term survival & sustainability
The skills that we should be developing from school
To solve environmental problems, we must be critical thinker who can seek new facts, learn new skills, form new ideas to test
Reasoning
Evaluation
Problem solving
Cycle of critical thinking
Critical thinkers have produced new technologies that can help with many environmental problems
Renewable energy
Only works in some conditions
Must be able to store energy for when it can't collect the energy
Takes up a lot of space
Solar panels
Taking food scraps and isolating them - composting
Composting: organic material decomposes and forms soil that can be used - the nutrients are recycled
Not everything put in the “blue bin” is recycled - only about 30-40% (e.g. bottles, bags, etc.)
Ozone depletion in the upper atmosphere was detected by satellite technology
Aerosol CFCs were banned in 1987 when it was determined that they were causing the loss
Since then, the ozone levels have increased and continue to improve
Freeon used to release CFC, it worked well at cooling things down (e.g. fridges, coolers, AC)