© 2011 Pearson Education, Inc. AP Environmental Science Mr. Grant Lesson 82 Environmental Health

© 2011 Pearson Education, Inc. Objectives: Define the term environmental toxicology. Explain the goals of environmental health and identify major environmental health hazards.

© 2011 Pearson Education, Inc. Define the term environmental toxicology. Environmental Toxicology Environmental toxicology deals specifically with toxic substances that come from or are discharged into the environment, and includes the study of health effects on humans, other animals, and ecosystems.

© 2011 Pearson Education, Inc. Explain the goals of environmental health and identify major environmental health hazards. Environmental Health seeks to assess and mitigate environmental factors that adversely affect health and the ecological systems. Environmental Health threats include physical, chemical, biological, and cultural hazards Disease is a major focus of environmental health. We have successfully fought some infectious diseases, but others are spreading. Sanitation, clean water, food security, education, and access to medical care are strategies to enhance environmental health. Toxicology is the study of poisonous substances. Several major environmental hazards (cigarette smoke, radon, asbestos, lead, and PBDEs) exist indoors.

© 2014 Pearson Education, Inc. Environmental Health  Environmental health  field that assesses environmental factors that influence human health and quality of life  Including natural and human-caused factors  Practitioners seek to prevent adverse effects on human health and ecological systems  Many environmental health hazards exist in the world around us

© 2014 Pearson Education, Inc. We face four types of environmental hazards  Physical hazards  hazards that occur naturally in our environment  Exposure to ultraviolet (UV) radiation from sunlight  Earthquakes, volcanoes, fires, floods, droughts  We can’t prevent them, but we can prepare for them  We increase our vulnerability by deforesting slopes (e.g., landslides), channelizing rivers (e.g., flooding), etc.  We can reduce risk with better environmental choices

© 2014 Pearson Education, Inc. We face four types of environmental hazards  Chemical hazards  synthetic chemicals such as pharmaceuticals, disinfectants, pesticides  Harmful natural chemicals (e.g., venom) also exist and chemicals that we take from nature and process

© 2014 Pearson Education, Inc. We face four types of environmental hazards  Biological hazards  result from ecological interactions  Viruses, bacteria, and other pathogens  Infectious disease  disease occurring when species parasitize humans, fulfilling their ecological roles  Vector = an organism that transfers a pathogen  We can’t avoid risk, but we can reduce infection

© 2014 Pearson Education, Inc. We face four types of environmental hazards  Cultural hazards  result from where we live, our socioeconomic status, our occupation, our behavioral choices  Smoking, drug use, diet and nutrition, crime, mode of transportation— some we control, others we can not  Health factors (e.g., living near toxic waste) are often correlated with poverty

© 2014 Pearson Education, Inc. Disease is a major focus of environmental health  Despite our technology, disease kills most of us  Disease has a genetic and environmental basis  Cancer, heart disease, respiratory disorders have some genetic basis  Air pollution, poverty, and poor hygiene foster illnesses  Noninfectious diseases cause over half of the world’s deaths  Infectious diseases account for 1 in 4 deaths  15 million people/year

© 2014 Pearson Education, Inc.

Disease is a major focus of environmental health  Where you live helps determine your disease  Infectious disease causes half of all deaths in developing countries  Money lets developed countries have access to hygiene and medicine to combat these diseases

© 2014 Pearson Education, Inc. Disease is a major focus of environmental health  Lifestyles in developed nations affect diseases  U.S. smoking dropped 42%  But obesity has more than doubled  Public health efforts decrease some infectious diseases  But some (AIDS) are spreading  Some develop resistance to antibiotics

© 2014 Pearson Education, Inc. Social and environmental factors can influence the spread of infectious disease  Our mobility spreads diseases worldwide  Severe acute respiratory syndrome (SARS) in 2003  H1N1 swine flu in 2009–2010  Climate change will expand the range of diseases  New disease threats may arise  Some pathogens evolve rapidly  Humans can alter existing diseases to make them more deadly—bioterrorism is a growing concern  To predict and prevent diseases, experts deal with complicated interrelationships between technology, land use, and ecology

© 2014 Pearson Education, Inc. We are fighting disease with diverse approaches  One of the best way to reduce disease is to improve the basic living conditions of the poor  Food security, sanitation, clean drinking water  Also, provide expanded access to health care  Health clinics, immunizations, pre- and postnatal care

© 2014 Pearson Education, Inc. We are fighting disease with diverse approaches  Education campaigns work in rich and poor nations  Agencies, organizations, and governments work together  The United Nations, the World Health Organization, U.S. Agency for International Development, etc.  Private organizations donate millions of dollars  The Bill and Melinda Gates Foundation has donated over $15 billion to global health programs since 1994

© 2014 Pearson Education, Inc. Toxicology is the study of chemical hazards  Toxicology  the study of the effects of poisonous substances on humans and other organisms  Toxicity  the degree of harm a toxicant can inflict  Toxicant  any toxic substance (poison)  “The dose makes the poison”: toxicity depends on the combined effect of the chemical and its quantity

© 2014 Pearson Education, Inc. Toxicology is the study of chemical hazards  We have been adding increased amounts and numbers of chemicals into the environment around us  Environmental toxicology  deals with toxic substances that come from or are discharged into the environment  Studies health effects on humans, other animals, and ecosystems

© 2014 Pearson Education, Inc. Many environmental health hazards exist indoors  Americans spend roughly 90% of their lives indoors  Indoor spaces can be rife with hazards  Radon  a highly toxic, radioactive gas that is colorless and undetectable  Can build up in basements  Found in areas with certain types of bedrock  Asbestos  a mineral that insulates, muffles sounds, and resists fire  Asbestosis  disorder that occurs when inhaled crystals of asbestos cause scarred lungs that cease to function  Can lead to lung cancer

© 2011 Pearson Education, Inc. Environmental health hazards exist indoors

© 2014 Pearson Education, Inc. Many environmental health hazards exist indoors  Lead poisoning  caused by lead, a heavy metal  Damages the brain, liver, kidney, and stomach  Causes learning problems, behavior abnormalities, and death  Exposure is from drinking water that flows through lead pipes or from lead paint  Efforts in the United States have led to declines in poisoning, but China still used lead paint in toys until recently  In 2012, the Centers for Disease Control (CDC) cut the danger threshold for lead in children’s blood from 10 to 5 micrograms/deciliter

© 2014 Pearson Education, Inc. Many environmental health hazards exist indoors  Polybrominated diphenyl ethers (PBDEs)  a group of chemicals with fire-retardant properties  Used in computers, televisions, plastics, and furniture  Persist and accumulate in living tissue  Mimic hormones and affect thyroid hormones  Also affect brain and nervous system development and may cause cancer  Concentrations are rising in breast milk  Now that they’re banned in Europe, concentrations have decreased  The United States has not addressed the issue

© 2014 Pearson Education, Inc. Risks must be balanced against rewards  As with most hazards, there is a tradeoff between the risk of harm and reward  We must judge how these compare  We use bisphenol A despite its health risks  Are safer and affordable alternatives available?  Chemicals have given us our high standard of living  Food, medicine, conveniences