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This chapter focuses on air quality. Topics discussed include an overview of air pollution, common health effects of ambient air pollution, health effects of specific air pollutants, industrial air pollution, and air pollution and the community.

This chapter discusses outdoor air pollution in school environments. Outdoor (ambient) air pollution presents a number of issues in the school environment, including exposure of children to diesel exhaust from older buses, potential risks for students who play or exercise outdoors on smoggy days, and exposure to emissions from nearby traffic and industrial facilities. There are steps that school administrators can take to protect children and address pollution. These include limiting outdoor activities on high ozone days, keeping students indoors for recess and practices, and contacting the air pollution control authority with any concerns about sources of pollution very close to the school, and discuss the record of the polluting facility.

This chapter describes several situations in which free radicals/reactive species (RS) are especially problematic and require special protective mechanisms. The first is the gastrointestinal tract, which is exposed to pro-oxidants from the diet and must protect itself from oxidative damage using a range of antioxidants. It also produces some RS for useful purposes, including the regulation of bacterial colonization, by NADPH oxidase enzymes. The respiratory tract has to cope with inhaled air pollutants (O₃, NO₂, SO₂, and O₂ itself) and contains many antioxidants (especially GSH) in its lining fluids and cells. The relation of antioxidants (especially vitamin C) to asthma is also reviewed. Erythrocytes have special problems because of the haemoglobin they carry, which can oxidize to generate superoxide. Hence erythrocytes are rich in antioxidants. The effects of toxins (e.g. favism), glucose-6-phosphate dehydrogenase deficiency, and infection with malaria parasites on oxidative damage in erythrocytes are presented. Indeed, malaria can be treated with drugs that impose oxidative stress, such as artemisinin. Plants are discussed in detail, including the mechanisms of photosynthetic O₂ production, how plants protect themselves against O₂ toxicity (using many antioxidants, especially carotenoids), and how they can be damaged by poisons such as paraquat, air pollutants, atrazine, or oxyfluorfen. The problems of the ear and the involvement of RS in hearing loss are discussed. Conception (spermatozoa, ova), pregnancy, embryonic development, normal birth, and premature birth, and the action of teratogens are also considered in the free-radical/antioxidant context, as are the potential benefits and harm from exercise.

Chapter 3 presents the Oil Climate Index plus Gas (OCI+), the first open-source tool that assesses and compares the different climate effects of the wide range of oils produced around the world, taking into account upstream, midstream, and downstream emissions. The chapter walks through the motivation behind creating the OCI+ with collaborators from Stanford University and the University of Calgary. The underlying models composing the OCI+ are discussed and visualized in detail. Model data and uncertainty are fleshed out. The chapter discusses methods for evaluating OCI+ emissions using remote sensing, satellites that spot flares from space, and an expanding array of methane measurement instruments. Possible avenues to build out the OCI+ to include other air pollutants are presented. The chapter concludes by laying out estimated ranges of currently modeled emissions intensities of global oil and gas supplies.

This book chronicles almost five decades of efforts by the United States government to reduce the air pollution associated with burning coal, along with the often misleading political rhetoric surrounding those efforts. Given the central role that coal and its environmental consequences will play in our story, it’s helpful at the outset to understand some basic facts about the fuel. Short Answer: A combustible rock. Longer Answer: Coal is a fossil fuel—“fossil” because it’s primarily composed of the preserved remains of ancient plants and “fuel” because it can be burned to create energy. Most of the coal we use today was formed hundreds of millions of years ago when large swaths of the earth were covered in swampy forests. As plant life in these swamps died, it sank to the bottom of the water, where it was eventually buried under additional layers of sediment and slowly decomposed into a soggy, carbon-rich, soil-like substance known as peat. As still more time passed, this peat was further transformed by heat and pressure, a process known as carbonization, into the sedimentary rock we call coal. Short Answer: We mine it, mostly in Wyoming and Appalachia. Longer Answer: There are two basic methods of mining coal: underground mining and surface mining. Surface mining is typically used for shallow coal beds—those buried less than 200 feet deep. Miners access the fuel by simply removing (often with explosives) the trees and soil and rocks that sit atop it. Underground mining, by contrast, is used to extract coal that sits between 300 and 1,000 feet deep. The surface is left relatively undisturbed, and miners dig tunnels through which to enter the mine and retrieve the coal. Historically, underground mining was the more common of these two methods, but today, the majority of U.S. coal is produced at surface mines, which require far fewer workers to produce the same amount of coal. In addition to being cheaper to operate, surface mines are safer: both fatal and serious nonfatal injuries occur about three times more often in underground mines.