Gasoline

Health Hazards

As a hydrocarbon, gasoline is considered a hazardous substance and is regulated in the United States by the Occupational Safety and Health Administration. The material safety data sheet for unleaded gasoline shows more than 15 hazardous chemicals occurring in various amounts, including benzene (up to 5 percent by volume), toluene (up to 35 percent by volume), naphthalene (up to 1 percent by volume), trimethylbenzene (up to 7 percent by volume), methyl tert-butyl ether (up to 18 percent by volume, in some states), and about 10 others. Many of the nonaliphatic hydrocarbons naturally present in gasoline (especially aromatic ones like benzene), as well as many antiknock additives, are considered carcinogenic. Because of this, large-scale or constant leaks of gasoline pose a threat to the public's health and the environment in the event the gasoline reaches a public supply of drinking water. According to the Environmental Protection Agency (EPA), one gallon of gasoline can pollute 750,000 gallons of water.

Refining

In addition to the extraction of oil and its transportation to refineries, the first step to obtain gasoline is the refining process. This process releases a number of substances with extensive air-polluting potential into the atmosphere. A considerable odor normally [Page 312]accompanies the presence of a refinery. Aside from air pollution impacts, there are also wastewater concerns; risks of spills, fires, and explosions; and health effects due to industrial noise. A persistent problem linked to hydrocarbons is corrosion of the transportation lines and storage devices. Corrosion occurs in various forms in the refining process, such as pitting corrosion from water droplets, fractures in metals due to exposure to hydrogen, and stress corrosion cracking from sulfide attack. To prevent corrosion, carbon steel is normally used for upward of 80 percent of refinery components, which is beneficial due to its low cost.

In the United States, there is strong pressure to prevent the development of new refineries, and no major refinery has been built in the country since Marathon's Gary ville, Louisiana, facility in 1976. Since the 1980s, over 100 refineries have closed due to obsolescence or merger activity within the industry. Around the world, environmental and safety concerns have led to the construction of oil refineries some distance away from major urban areas. Nevertheless, the pace of urbanization makes this practice unsustainable. The possibility of disasters due to hydrocarbon spills in the vicinity of densely populated areas increases every year.

Spills and Cleanup

Most spills involving gasoline occur at the distribution phase. On June 10, 1999, a gasoline pipeline in Bellingham, Washington, owned by the Olympic Pipe Line Company ruptured, discharging approximately 236,000 gallons of gasoline into Hanna Creek. It then leaked into Whatcom Creek, a 3.5-mile-long coastal stream that runs through a city park, residential neighborhoods, and urban industrial areas before emptying into Bellingham Bay. As the gasoline was carried down the creek, the fumes were ignited, killing three people and affecting a variety of natural resources along the creek's path.

...