Lecture 1-5

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University of Toronto Scarborough
Environmental Science
Silvija Stefanovic

Your environment is your health According to the World Health Organization (WHO): Environmental Health: The human health, disease and injuries that are determined or influenced by factors in the environment. Anything that affects human health. This includes the study of both the direct and the indirect pathological effects of various: • Chemical • Biological • Physical • Social agents (housing, urban development, land use, transportation) Environment is everything that affects a living organism • Air • Water • Soil • Biota • Manmade environment Human Alteration to Environment: • Atmosphere: CO2 increased 30% since the beginning of the Industrial revolution • Geosphere: 1/3 to 1/2 of the land surface has been transformed by human action • Biosphere: Logging • Industrialization: Pollution • Overpopulation and overconsumption The declining health of other organisms is the clearest indicator of environmental threats to human health No single factor is responsible: • Increase UV • Traces of toxic chemicals • Infections (fungi and bacteria) • Predators Note:  Environmental factors responsible for 25 % of all preventable diseases  In a developing countries diarrhea and respiratory infections are heading the list  Protecting the environment has been a mainstay of public health practices since 1878  African Americans & Hispanic & Whites  Developed & developing countries Types of Hazard: • Chemical hazard o Chemicals in air, water, soil and food • Biological hazard o Bacteria, viruses, parasites, allergens, animals such as bees and poisonous snack • Social hazard o Unsafe working conditions, poor diet, drugs, drinking, driving, poverty • Physical hazard o Radiation, fire, tornado, hurricane, volcanic eruption, earthquake Lecture 2 London smog, 1952 Result of coal burning Indonesian Fires, 1997 Was trying to clean the land for agriculture • Asthma o Particulates and/or SO2 can irritate bronchial passages leading to severe difficulties in breathing • Chronic bronchitis o Occurs when an excessive amount of mucus is produced in bronchi which results in a lasting cough o SO2 and smoking is related to chronic bronchitis • Pulmonary emphysema o Weakening of the wall of alveoli, they become enlarged and loss their resilience o Shortness of breath is the primary symptom o NO2 is related to emphysema • Primary air pollutants o Particulate matter o Carbon monoxide (Incomplete Combustion) o Sulphur oxides (Burning of coal and oil, extraction of metals from ore ) o Lead o Nitrogen oxides (Any Combustion Process)  Form nitrate particles, acid aerosols  Contribute in formation of acid rain  Transported over long distances o VOC (Volatile Organic Compounds, Solvent in industry, automobiles  Hydrocarbons: methane, butane, propane • Secondary air pollutant o Ground level Ozone (stratosphere) o Ozone (VOC + NOx + Heat + Sunlight = Ozone )  Transported on long distances  Lung damage (small airways)  Shortness of breath, chest tightness, coughing and nausea  Irritate and damage eyes, nose, sinuses and throat Smog Smoke + Fog = Smog (1905) Six Common Indoor Air Pollutants • Asbestos (fibrous minerals) o Properties:  Have separable, long, strong and flexible heating resistant fibres o Used in:  Building materials  Friction products (automobile parts)  Heat resistant fabrics, packaging and coatings o Health Affect:  Affect the lungs and the membrane  Difficulty breathing,  heart enlargement, lead to disability and death • Formaldehyde o Properties:  Naturally occurring gases, colourless, strong smell  Released by burning wood and natural gas, by automobile and by cigarettes o Used in:  Glue or adhesives in press wood products  Preservatives in some paints and cosmetics  Coatings that provide permanent press quality to fabrics and draperies  Certain insulation materials o Health Affect:  Watery eyes, burning sensation in the eyes, nose and throat  Nausea, Skin rashes, allergic  Coughing, Chest tightness, cancer • Mold and Moisture o Health Affect:  Allergens  Trigger asthma  Produce Toxins  Produce Irritants • Second-hand Smoke o Properties:  Contain 4 000 compounds (CO and Formaldehyde), 40 are carcinogens o Health Affect:  25% increased chance of developing lung cancer  Eye, nose and throat irritation  Affect the cardiovascular system  Higher risk of asthma, pneumonia, ear infection, bronchitis in children • Radon Gas o Properties:  Colorless, odourless, tasteless  Naturally occurring • Air Dust o Health Affect:  Allergens  Asthma Lecture 3 Withdrawal - total amount of water removed from a river, lake or aquifer for any purpose.  Some may be returned to the source for reuse  Use about 54 % of the world's reliable runoff of surface water and could be using 70-90% by 2025 World’s problems  Some areas have lots of water but the largest rivers are far from agricultural and population centers  Lots of precipitation arrives during short period but cannot be collected and stored  Lakes and rivers shrinks  Diarrheal deaths kill over 2 million children annually Surface water - In urban areas  Rivers  Lakes  Springs  Cisterns Ground water- In rural areas  wells Quality of water  Water pH  Hardness  Color  Turbidity  Taste  Odor  Microbes and Chemicals Contaminants in Drinking Water • Microbes • Radionuclides • Inorganic Contaminants o Arsenic o Fluoride o Lead o Nitrates • Industrial Organic Contaminants o Pesticides and Herbicides o Volatile Organic Compounds (VOC) • Disinfection by-products 1. Microbes • Example: o Norwalk viruses, enteroviruses, adenoviruses - diarrheal illness o Hepatitis A- liver inflammation o Cryptosporidium – parasite that enters lake and rivers through sewage and animal wastes o Giardia lamblia - enters lake and rivers through sewage and animal wastes, diarrhea, vomiting, cramps 2. Radionuclides • Example: o Radon: a colorless and odorless gas • Health Affect o Damage to DNA, Increase risk of getting cancer o Cause several types of cancer if breathed or swallowed • Found o Normally, found in the basement. 3. Inorganic Contaminants: Arsenic • Health Affect: o High concentration of arsenic is poisonous o Lower concentrations can cause skin cancer o Drinking cause skin damage, and problems with circulatory system • Found: o 200 different minerals, usually in low concentrations • Fact: o Arsenic dissolves very readily in groundwater o Able to move long distances from its source Fluoride • Health Affect: o Fluoride concentration greater than 1.5 milligrams per liter can become potentially harmful o Exposure to high concentrations of fluoride can cause dental fluorosis and skeletal fluorosis (bone disease) • Found o Fluoride is found in the common mineral fluorite and in certain types of micas and clay minerals o Highest concentrations of fluoride are found in region of volcanic activity • Fact: o Fluoride ions are not really reactive, therefore, high levels of fluoride are typically found close to its source material o Added to promote dental health Lead: • Health Affect: o Anemia (Appear like zombie) o Brain, kidneys and nervous system damage o Abdominal pain o Sleeplessness o Headache o Miscarriages and stillbirths (Dead birth) o Most serious for young children (intellectual development, behavior, size and hearing of infants) • Fact: o Lead pipes are banned Nitrate • Health Affect: o Inhibits the red blood cell’s ability to transfer oxygen o Methemoglobinemia – oxygen starvation, cyanosis (bluish discoloration of the skin and lips) o Spontaneous abortion (Freaky) and neural tube defects Industrial Contaminants: Pesticides and Herbicides • Example: o Chlorinated Hydrocarbon o DDT, Chlordane, Lindane o Persistent, bio accumulating • Health Affect: o Not mammal-toxic o Very negative ecological effects • Example: o Organophosphates and Carbamate o Round-up - grasses o Metolachlor, Alachlor (weeds) o Triazine 2,4-D; 2,4,5-T (many plants) • Health Affect: o Not bio accumulating But Very mammal-toxic Industrial Contaminants: MTBE (Methil-Tert-Butyl Ether) • Properties: o Volatile o Flammable o Colorless liquid • Use: o Fuel additive, replace the use of lead as octane enhancer o Used to reduce carbon monoxide and ozone levels caused by auto emission Disinfection By-products Form when disinfectants react with naturally occurring organic and inorganic matter in water • Examples: o Trihalomethane – excess over many years cause liver, kidney, or central nervous system problems, increased risk of getting cancer o Haloacetic Acid – increased risk of getting cancer o Bromate – increased risk of getting cancer o Chlorite – children could experience nervous system effect, some people may experience anaemia Case Study: • Walkerton example (E.coli) • The surface of a water pipe containing bacteria, isolated from Walkerton during the investigation in 2000. Case Study: • Concentrations of arsenic in groundwater from wells in Bangladesh. Concentrations above 50 μg per liter are harmful to human health. Approximately 25% of the wells exceed the recommended maximum safe concentration. Case Study: • Groundwater in aquifer in semiarid basins in the Basin and Range area of Nevada and Arizona comes from rainfall on the higher ranges. If these rocks contain arsenic, concentrations in the groundwater of the basin will be the result. Case Study: • Areas in Nova Scotia (orange) where well water is likely to have arsenic concentrations in excess of 10 μg per liter Case Study: • Outcrop of alternating black shale (black) and sandstone (buff) beds at “The Ovens”, Cunard Cove, near Lunenburg, Nova Scotia. As in many black shale beds, arsenic is also present. Case Study: • Fluorosis is widespread in India, primarily as the result of drinking water or eating food with anomalously high fluoride concentrations. Areas underlain by granites have the highest rates of fluorosis. Case Study: • Areas in Africa with excessive concentration of fluoride in groundwater. Note the high concentrations along the East African Rift Valley. Case Study: • The farming community of Maria, Quebec, had previously relied on groundwater drawn from shallow wells dug in glacial sediment. In the early 1970s, deeper
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