CHAPTER 15 ENVIRONMENTAL CONCERNS: WASTES AND POLUTION. 487 centre d Mary recently accepted jobs as teachers chemicals. The sanitarian recommended that Tom the Blackford school Corporation. When they and Mary drink bottled water until the well water moved to the Blackford community, they pur could be tested further. After some investigation, chased a modest home on five acres of land out county officials determined that Mary and Toms side the city. They had only been living in their 15-year-old home had been built close to a former new home two months when they noticed that landfill that had been closed about 20 years ear their water was beginning to taste different The lier. Tom and Mary were now faced with an ource of their water was a well on their own expensive, unforeseen, and long-term problem, not property. A testing of the water by the local health to mention the devaluation of their property. department sanitarian revealed that their water was contaminated with lead and perhaps other INTRODUCTION health are affected by the quality of our environment, and the way we live our lives& As human beings, we are a part of the environment in which we live. Our lives and all the external influences the quality of the environment. In this chapter we explain in detail and I inin r illustrate with examples the ways in which our interactions with the environment surrounding and have direct consequences for the quality of our lives. While this chapter seeks to and develogment of describe and define wastes and pollution, Chapter 16 examines more specifically an organism or The environment is defined as all the external conditions, circumstances and/ ogontramro the health consequences of these environmental hazards influences surrounding and affecting the growth and development of an organism or a community of organisms. In order to fully understand environmental concerns that threaten our health, we must understand how we interact with our environ- ecology ment. The study of how living things interact with each other and their environ- between organisms ment is called ecology, and the zone of the earth where life is found is known as and their evironment the biosphere. NATURAL ENVIRONMENTAL HAZARDS biosphere the zone of the earth where life is found While the purpose of this chapter is to point out and explain environmental hazards associated with human activities, it is important to recognize the ex tence and influence of natural hazards in the environment that damage or destroy wildlife habitats, kill or harm humans, and damage property. These hazards naiural hazards may be physical, biological, chemical, or even psychological or social. Physical that incease hazards are caused by forces either internal to the earth's surface or on the sur- proboliltyof disease face itself. Natural hazards resulting from internal forces include earthquakes and iniury or death volcanos. Those on the surface include winds lightning, storms, floods, fires, and of humans drough