Health: The Basics - Chapter 13 - Environmental Health

Health: The Basics Fifth Canadian Edition Rebecca J. Donatelle Angela M. Thompson Chapter 13...

Health: The Basics Fifth Canadian Edition Rebecca J. Donatelle Angela M. Thompson Chapter 13 Environmental Health: Thinking Globally, Acting Locally Mary McKenna PowerPoint® Lecture Slide Presentation Copyright © 2011 Pearson Canada Inc. Learning Objectives Explain the impact of global population growth on the environment Identify the major causes of air pollution and offer suggestions for reducing it Identify major sources of water pollution and offer suggestions for reducing it Describe consequences of noise pollution and what you can do to protect yourself Identify the major causes of land pollution and what can be done to reduce it Copyright © 2011 Pearson Canada Inc. 13-2 Overpopulation Effective management of the environment is needed to avoid at least 25% of all preventable diseases worldwide 13 million deaths could be prevented annually if the environment were healthier Unsafe water and air pollution causes 4 million deaths annually in children under 5 Promoting safe household water storage, better hygiene, and cleaner and safer fuels would reduce disease and death Thousands of Canadians are changing their habits and working to improve the environment Copyright © 2011 Pearson Canada Inc. 13-3 Overpopulation 2010 world population estimate 6.9 billion Prediction for 2050 = 9.2 billion Majority of population growth occurs in developing world Estimates for population growth depend on fertility rates and life expectancy As the world’s population increases so does competition for the earth’s resources North Americans consume more energy and raw materials per person than any other region of the world Copyright © 2011 Pearson Canada Inc. 13-4  Figure 13.1: Major Pathways of Human Exposure to Environmental Contaminants Copyright © 2011 Pearson Canada Inc. 13-5 Air Pollution Sources of Air Pollution Sulphur Dioxide Particulates Carbon Monoxide Nitrogen Dioxide Ozone Lead Hydrocarbons Copyright © 2011 Pearson Canada Inc. 13-6 Air Pollution Photochemical Smog Brown, hazy mix of particulates and gases Sometimes called ozone pollution Often occurs in areas of temperature inversion – layer of cool air trapped under a layer of warm air May result in: difficulty breathing, burning eyes, headaches, and nausea Long term: may cause serious effects, especially among vulnerable people Copyright © 2011 Pearson Canada Inc. 13-7 Air Pollution Acid Rain Precipitation contaminated with acidic pollutants Sources of Acid Rain − burning fossil fuels Effects of Acid Rain − environmental damage − respiratory problems − leaching of metals out of the soil − crop damage − damage to monuments and structures Copyright © 2011 Pearson Canada Inc. 13-8 Air Pollution Indoor Air Pollution Wood Stove Smoke Furnaces Asbestos Passive Smoke Formaldehyde Radon Household Chemicals Copyright © 2011 Pearson Canada Inc. 13-9 Air Pollution Ozone Layer Depletion Chemical produced when oxygen interacts with sunlight Protective membrane-like layer in earth’s atmosphere Depletion of the ozone layer by chlorofluorocarbons (CFCs); production and importation now banned in Canada Copyright © 2011 Pearson Canada Inc. 13-10 Air Pollution Global Warming Greenhouse gases produced by burning fossil fuels May be most economically disruptive and costly change of our modern society Reducing Air Pollution Need to change energy, industry, and transportation Encourage use of renewable resources such as solar, wind, and water power Copyright © 2011 Pearson Canada Inc. 13-11  Figure 13.2: This diagram shows the depletion of the stratospheric ozone layer Copyright © 2011 Pearson Canada Inc. 13-12 Water Pollution 75% of the earth is covered with water Water Contamination Point source – specific entry point Non-point source – seep into waterways − Septic Systems − Landfills − Gasoline and Petroleum Products − Dioxins Copyright © 2011 Pearson Canada Inc. 13-13 Water Pollution Chemical Contaminants Polychlorinated biphenyls (PCBs): toxic chemicals once used as insulating materials in high-voltage electrical equipment Pesticides: chemicals designed to kill insects, rodents, plants, and fungi Trihalomethanes: synthetic chemicals formed as a by-product of water treatment Lead: mineral that can damage health Copyright © 2011 Pearson Canada Inc. 13-14  Figure 13.4: Sources of Groundwater Contamination Copyright © 2011 Pearson Canada Inc. 13-15 Noise Pollution Loud noises are common and are a source of physical and mental distress Short-term exposure reduces productivity, concentration, attention span, and may affect health Symptoms of noise related distress include: sleep disturbance, headaches and tension, and negative impacts on physical health Prevent hearing loss: Play stereos at reasonable levels Wear earplugs for power equipment Establish barriers to noise Copyright © 2011 Pearson Canada Inc. 13-16 Land Pollution Solid Waste Reduce, reuse, recycle As much as 90% of garbage could be reused or recycled Hazardous Waste Solid waste that poses a hazard to humans or the environment The Canadian Environmental Protection Agency program to deal with hazardous wastes − elimination or reduction Copyright © 2011 Pearson Canada Inc. 13-17 Radiation Substance is radioactive when it emits high-energy particles from the nuclei of its atoms Types of radiation: alpha particles, beta particles, and gamma rays Ionizing Radiation Exposure is inescapable Can damage genetic material Most of us exposed to far less than “safe” maximum dosage Copyright © 2011 Pearson Canada Inc. 13-18 Radiation Nonionizing Radiation Little is known about the biologic effects of certain types of nonionizing radiation Nuclear Power Plants Account for less than 1% of total radiation exposure Proponents feel it is safe and efficient Concerns about disposal of nuclear waste and chances of a meltdown Copyright © 2011 Pearson Canada Inc. 13-19 Food Quality Food accounts for 80 to 95% of intake of the most persistent toxic contaminants Air contributes 10 to 15% and drinking water contributes very little Canada’s food is some of the safest in the world Concerns about microbial and environmental contamination in food Individuals can take steps to reduce risk Copyright © 2011 Pearson Canada Inc. 13-20