Environmental Health Chapter 15 PDF

Because learning changes everything. ® Environmental Health Chapter 15 © McGraw Hill LLC. All rights reserved....

Because learning changes everything. ® Environmental Health Chapter 15 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC.  Environmental Health Defined Environmental health is concerned with the collective interactions of humans with their environment and the health consequences of these interactions: Environment: Everything that surrounds us. Environmental pollutants contribute to infectious diseases, immediate symptoms, and chronic diseases as well. Technological advances have increased our ability to affect and damage the environment. Rapid population growth means more competition for and consumption of resources. © McGraw Hill LLC 2  Population Growth and Control 1 World population: currently around 7.8 billion Increasing at a rate of 80 million per year How many people can the world hold? We use as many ecological resources as if we lived on 1.6 earths. Factors that may eventually cap population: Food Available land and water Energy Minimum acceptable standard of living © McGraw Hill LLC 3  Population Growth and Control 2 Factors that contribute to population growth: High birth rates and lack of family planning resources Lower death rates Successful population management must provide for: Less poverty, to remove the pressures to have large families Improved health Better education Increased literacy and employment opportunities for women Family planning © McGraw Hill LLC 4  Figure 15.1 World population growth. The United Nations estimates that the world population will reach 8.5 billion in 2030, 9.7 billion in 2050, and 10.9 billion in 2100. Access the text alternative for slide images. © McGraw Hill LLC SOURCE: United Nations. 2019. World Population Prospects: The 2019 Revision (https://population.un.org/wpp/). 5  Environmental Impacts of Energy Use and Production Energy consumption is at root of many environmental problems. Automobile exhaust and the burning of oil and coal by industry and by electric power plants Mining of coal and the extraction and transportation of oil and natural gas cause pollution on land and in the water. © McGraw Hill LLC 6  Figure 15.2 Energy consumption of selected countries. Access the text alternative for slide images. SOURCE: U.S. Energy Information Administration. 2021. International Energy Statistics: Total Primary Energy Consumption (Quadrillion BTU): All Countries, 2019 (http://www.eia.gov/international/rankings/world?). © McGraw Hill LLC 7  Environmental Threats of Extreme Energy Sources Worldwide energy demand is expected to continue to increase over time, even while supplies of easily accessible oil will decline. “Extreme energy sources” are fossil fuels that are relatively difficult to access and extract: Deepwater oil rigs Tar sands oil extraction Drilling and hydraulic fracturing (“fracking”) for natural gas extraction All of these pose significant new environmental risks. © McGraw Hill LLC 8  Renewable Energy Renewable energy sources are naturally replenished and essentially inexhaustible. Sustainable development: the development that meets society’s present needs without compromising the ability of future generations Some of our best sources of renewable energy: Wind power Solar power Geothermal power Biomass Biofuels © McGraw Hill LLC 9  Alternative Fuels Ethanol: An alcohol made from plant sugars. Critics claim it requires more energy to produce than it yields and diverts crops from the food supply. Although ethanol production dropped in 2020 due to the Covid-19 pandemic, it will likely remain an important alternative fuel as the economy recovers. Biodiesel: Biodiesel fuel can likewise be problematic depending on its material source. © McGraw Hill LLC 10  Hybrid and Electric Vehicles Hybrid electric vehicles (HEVs) use two or more distinct power sources to propel the vehicle: Such as batteries, a traditional internal combustion engine, and an electric motors Greater fuel economy and fewer polluting emissions Second generation of all-electric vehicles (EVs) has recently been introduced. © McGraw Hill LLC 11  Air Quality and Pollution WHO estimates that air pollution accounts for an estimated 4.2 million deaths per year. Air quality and smog: Air quality index (AQI) indicates whether air pollution poses a health concern. Used for five major air pollutants: Carbon monoxide (CO), sulfur dioxide (SO2), nitrogen dioxide (NO2), particulate matter (PM), and ground-level ozone AQI values run from 0 to 500: When it exceeds 100, air quality is unhealthful Smog is a mixture of other pollutants from car exhaust, power plants, and factory emissions. Heavy motor vehicle traffic, high temperatures, and sunny weather can increase the production of ozone. © McGraw Hill LLC 12  The Greenhouse Effect and Global Warming 1 Earth’s temperature depends on a balance between energy absorption and the amount of energy radiated. Greenhouse effect: reradiation causes a buildup of heat that raises the temperature of the lower atmosphere Global warming, or climate change, is caused by the concentration of greenhouse gases: Increased rainfall and flooding Increased mortality from heat stress, urban pollution, tropical disease, and extreme weather A poleward shift in the location of vegetation zones Alterations of ecosystems Increasingly rapid and drastic melting of the polar ice caps © McGraw Hill LLC 13  Figure 15.3 The greenhouse effect. Access the text alternative for slide images. © McGraw Hill LLC titoOnz/Alamy Stock Photo 14  Table 15.1 Sources of Greenhouse Gases GREENHOUSE GAS SOURCES Carbon dioxide Fossil fuel and wood burning, factory emissions, car exhaust, deforestation Chlorofluorocarbons (CFCs) Refrigeration and air conditioning, aerosols, foam products, solvents Methane Cattle, wetlands, rice paddies, landfills, gas leaks, coal and gas industries Nitrous oxide Fertilizers, soil cultivation, deforestation, animal feedlots and wastes Ozone and other trace gases Photochemical reactions, car exhaust, power plant emissions, solvents © McGraw Hill LLC 15  Figure 15.4 Impact of climate change on human health. Climate change can influence health and disease in many ways; the effects may vary based on location, age, socioeconomic status, and other factors. Access the text alternative for slide images. © McGraw Hill LLC SOURCE: Centers for Disease Control and Prevention. 2020. Climate Effects on Health (http://www.cdc.gov/climateandhealth/effects). 16  Thinning of Ozone Layer Another air pollution problem is the thinning of the ozone layer. A fragile, invisible layer about 10–30 miles above the earth’s surface shields the planet from the sun’s hazardous UV rays. Being destroyed primarily by chlorofluorocarbons (CFCs): Coolants in refrigerators Foaming agents Propellants Solvents Life on earth would be impossible without the ozone layer. © McGraw Hill LLC 17  Indoor Air Quality (IAQ) Indoor pollutants are linked to a range of problems. Common indoor air pollutants: Environmental tobacco smoke (ETS) Carbon monoxide and other combustion by-products Volatile organic compounds (VOCs) Biological pollutants Indoor mold © McGraw Hill LLC 18  Preventing Air Pollution Cut back on driving and keep Ventilate your home. your car well maintained. Tightly seal paint and other Buy energy-efficient appliances chemical containers. and use them only when Don’t smoke or allow smoking in necessary. your home. Use energy-efficient lighting. Clean and inspect chimneys, Insulate your home with ozone- furnaces, other appliances. safe agents. Always use an outside venting Plant and care for trees. hood when cooking. Identify a local waste hauler Use paints with low or no VOCs. who removes ozone-depleting Keep areas mold-free. refrigerants from disposed Use a HEPA air filter. refrigerators. © McGraw Hill LLC 19  Water Quality and Pollution 1 Water contamination and treatment: Ensuring safe, clean drinking water Purifying water in water-treatment plants: Screening Filtration Disinfection (chlorine) Fluoridation: Reduces tooth decay by 15–40 percent Some controversy over its safety for human health © McGraw Hill LLC 20  Water Quality and Pollution 2 Water shortages: Rapid population growth taxes the water system. World Health Organization: Two billion people do not have safe drinking water. Around 4.5 billion do not have access to safely managed sanitation. Sewage: Residual sludge from sewage treatment is often contaminated with heavy metals and chemicals such as lead, cadmium, copper, and tin. © McGraw Hill LLC 21  Protecting the Water Supply Take showers, not baths. Install faucet aerators and water-efficient showerheads. Replace old toilets. Fix any leaky faucets. Do not pour toxic materials down the drain. Do not flush old medications. © McGraw Hill LLC 22  Solid Waste Pollution 1 Biggest single component of household trash by weight is paper products. Food, yard waste, and plastic are other components. About 1 percent of solid waste is toxic. Computer components. Manufacturing, mining, and other industries all produce large amounts of potentially dangerous materials that cannot simply be dumped. Disposing of solid waste: Sanitary landfill disposal sites have several disadvantages. © McGraw Hill LLC 23  Solid Waste Pollution 2 Biodegradable: certain products that can break down naturally, safely, and quickly into raw materials: Products that are compostable may break down through biotic and abiotic processes. Recycling uses waste materials as raw materials in the production of new products. Discarded technology: e-waste: Americans produce about 7 million tons of e-waste per year (42 pounds per person). © McGraw Hill LLC 24  Figure 15.5 Components of municipal solid waste, by weight, before recycling. Access the text alternative for slide images. © McGraw Hill LLC SOURCE: U.S. Environmental Protection Agency. 2022. Advancing Sustainable Materials Management: 2018 Fact Sheet (Pub. No. 530-F-20-009). Washington, DC: EPA. 25  Table 15.2 How Long Items Take to Biodegrade ITEM TIME REQUIRED TO BIODEGRADE Banana peel 2–10 days Paper 2–5 months Rope 3–14 months Orange peel 6 months Wool sock 1–5 years Cigarette butt 1–12 years Plastic-coated milk carton 5 years Aluminum can 80–100 years Plastic bottle 450 years Plastic six-pack holder ring 450 years Disposable diapers 500 years Plastic bag 1000 years Glass bottle 1 million years Styrofoam Does not biodegrade © McGraw Hill LLC 26  Reducing Solid Waste Limit your purchase and use of plastic products. Buy products with the least amount of packaging. Buy recycled or recyclable products. Use your own reusable containers and utensils at work. Use reusable containers to store food. Take foam pellets to a commercial mailing center that accepts them for recycling. Do not throw away electronic items—recycle them. Start a compost pile. © McGraw Hill LLC 27  Chemical Pollution and Hazardous Waste 1 Asbestos: Widely used for fire protection and insulation in buildings until the late 1960s. Causes asbestosis, lung cancer, and other serious lung diseases. Lead: In pipes and paints (until banned in 1978). Presence of lead pipes contributed to the drinking water crisis in Flint, Michigan. © McGraw Hill LLC 28  Chemical Pollution and Hazardous Waste 2 Pesticides: Pesticides are chemicals that kill unwanted pests. Herbicides (plant killers) and insecticides (insect killers) are used extensively in agriculture. Often have toxic effects on unwanted targets. Buildup in the food change through biomagnification. Mercury: From coal-fired power plants, mining and smelting operations, and consumer products Damages nervous and other body systems Bioaccumulates—large, long-lived fish carry high levels of mercury © McGraw Hill LLC 29  Chemical Pollution and Hazardous Waste 3 Other chemical pollutants: Dispose of hazardous wastes in the home properly. Preventing chemical pollution. Read labels and try to buy the least toxic products. Eat and live organically. Dispose of your household hazardous waste properly. Buy organic and local produce. Store pesticides or toxic household products in a locked place. Hire a licensed exterminator. © McGraw Hill LLC 30  Radiation Pollution Radiation differs in wavelength and energy; shorter waves have the highest energy level. Ultraviolet rays, microwaves, X-rays, from the sun, electronics, uranium, and nuclear weapons. Gamma rays at high doses can cause radiation sickness and death. Nuclear weapons and nuclear energy. Nuclear power was first developed as alternative power. Accidents in nuclear plants have been disastrous. Problem of waste disposal. Medical uses of radiation: X-rays © McGraw Hill LLC 31  Radiation in the Home and Workplace Electromagnetic radiation: Microwave ovens and computer monitors Cell phones Radon gas is radioactive. Avoiding radiation: Only get X-rays when necessary. Follow recommendations for radon testing. Use sunscreen and clothing. © McGraw Hill LLC 32  Noise Pollution Prolonged exposure to sounds above 80–85 decibels can cause permanent hearing loss. Some ways to avoid exposing yourself to excessive noise: Wear ear protectors when working around noisy machinery. When listening to music on a headset, set the volume below 60 percent of the maximum. For children, avoid toys that make loud noise. Avoid exposure to painfully loud sounds and repeated exposure to any sounds above 80 decibels. © McGraw Hill LLC 33  Figure 15.6 The intensity of selected sounds. Access the text alternative for slide images. Stocktrek/age fotostock; Stockbyte/Getty Images; Daxiao Productions/Shutterstock; Brand X Pictures/Getty Images; Pacific Northwest Photo/Shutterstock; Siede Preis/Photodisc/Getty Images; JupiterImages/Comstock Images/Getty Images; Stockbyte/Getty Images; Ken Karp/McGraw Hill; Jupiterimages/Stockbyte/Getty Images © McGraw Hill LLC 34  Review 1 Explain the concept of environmental health and how it has developed. Explain how population growth affects the earth’s environment. Explain the impact of energy use and production on the environment. Describe the causes and effects of air and water pollution. © McGraw Hill LLC 35  Review 2 Describe the problem of solid waste disposal. Identify environmental issues related to chemical pollution and hazardous waste. Identify environmental issues related to radiation pollution. Explain the concept of noise pollution and its impacts. © McGraw Hill LLC 36  Because learning changes everything. ® www.mheducation.com © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC.