Hempcar.org-Pollution: Petrol vs Hemp

• Overall ozone (smog) forming potential of biodiesel is less than diesel fuel. The ozone forming potential of the speciated hydrocarbon emissions was nearly 50 percent less than that measured for diesel fuel.1

• Sulfur emissions are essentially eliminated with pure biodiesel. The exhaust emissions of sulfur oxides and sulfates (major components of acid rain) from biodiesel were essentially eliminated compared to sulfur oxides and sulfates from diesel.1

• Criteria pollutants are reduced with biodiesel use. The use of biodiesel in an unmodified Cummins N14 diesel engine resulted in substantial reductions of unburned hydrocarbons, carbon monoxide, and particulate matter. Emissions of nitrogen oxides were slightly increased.1

• Carbon Monoxide: The exhaust emissions of carbon monoxide (a poisonous gas) from biodiesel were 50 percent lower than carbon monoxide emissions from diesel.1

• Particulate Matter: Breathing particulate has been shown to be a human health hazard. The exhaust emissions of particulate matter from biodiesel were 30 percent lower than overall particulate matter emissions from diesel.1

• Hydrocarbons: The exhaust emissions of total hydrocarbons (a contributing factor in the localized formation of smog and ozone) were 93 percent lower for biodiesel than diesel fuel.1

• Nitrogen Oxides: NOx emissions from biodiesel increase or decrease depending on the engine family and testing procedures. NOx emissions (a contributing factor in the localized formation of smog and ozone) from pure (100%) biodiesel increased in this test by 13 percent. However, biodiesel's lack of sulfur allows the use of NOx control technologies that cannot be used with conventional diesel. So, biodiesel NOx emissions can be effectively managed and efficiently eliminated as a concern of the fuel's use.1

• Biodiesel reduces the health risks associated with petroleum diesel. Biodiesel emissions showed decreased levels of PAH and nitrited PAH compounds which have been identified as potential cancer causing compounds. In the recent testing, PAH compounds were reduced by 75 to 85 percent, with the exception of benzo(a)anthracene, which was reduced by roughly 50 percent. Targeted nPAH compounds were also reduced dramatically with biodiesel fuel, with 2-nitrofluorene and 1-nitropyrene reduced by 90 percent, and the rest of the nPAH compounds reduced to only trace levels.1

• Acute Oral Toxicity/Rates: Biodiesel is nontoxic. The acute oral LD50 (lethal dose) is greater than 17.4 g/Kg body weight. By comparison, table salt (NaCL) is nearly 10 times more toxic.1

• Skin Irritation: A 24-hr. human patch test indicated that undiluted biodiesel produced very mild irritation. The irritation was less than the result produced by a 4 percent soap and water solution.1

• Aquatic Toxicity: A 96-hr. lethal concentration for bluegill of biodiesel grade methyl esters was greater than 1000 mg/L. Lethal concentrations at these levels are generally deemed "insignificant" according to NIOSH (National Institute for Occupational Safety and Health) guidelines in its Registry of the Toxic Effects of Chemical Substances.1

• Biodegradability: Biodiesel degrades about four times faster than petroleum diesel. Within 28 days, pure biodiesel degrades 85 to 88 percent in water. Dextrose (a test sugar used as the positive control when testing biodegradability) degraded at the same rate. Blending biodiesel with diesel fuel accelerates its biodegradability. For example, blends of 20 percent biodiesel and 80 percent diesel fuel degrade twice as fast as #2 diesel alone.1

• Flash Point: The flash point of a fuel is defined as the temperature at which it will ignite when exposed to a spark or flame. Biodiesel's flash point is over 300 deg. Fahrenheit, well above petroleum based diesel fuel's flash point of around 125 deg. Fahrenheit. Testing has shown the flash point of biodiesel blends increases as the percentage of biodiesel increases. Therefore, biodiesel and blends of biodiesel with petroleum diesel are safer to store, handle, and use than conventional diesel fuel.1

Although the concept of ethanol as a fuel began as early as the first Model T car designed by Henry Ford, American usage of ethanol-blended gasoline did not begin until the late 1970s. Environmentally, the use of ethanol blends has since assisted in reducing carbon monoxide emissions as mandated by the U.S. Clean Air Act of 1990.2

Net Reduction in Ground-level Ozone Forming Emissions: Ground-level ozone causes human respiratory problems and damages many plants but does nothing to increase ozone concentration in the stratosphere that protects the earth from the sun's ultraviolet radiation. There are many compounds that react with sunlight to form ground-level ozone, which, in combination with moisture and particulate matter, creates 'smog', the most visible form of air pollution. These compounds include carbon monoxide, unburned hydrocarbons, benzene, and nitrogen oxides (nitrous oxide and nitric oxide).2

In an effort to reduce automobile emissions that contribute to the formation of ground-level ozone, the highly populated state of California has legislated stringent automobile emissions standards. Several Canadian urban centers record similar hazardous exposures to carbon monoxide, especially during late fall and winter, and would be out of compliance if Canada implemented air quality legislation equivalent to the U.S. Clean Air Act. In Canada, southern Ontario, southern British Columbia, and parts of Nova Scotia and New Brunswick are prone to smog. Using oxygenated fuels, such as ethanol, is one way of addressing the issue of air pollution.2

The net effect of ethanol use results in an overall decrease in ozone formation. The emissions produced by burning ethanol are less reactive with sunlight than those produced by burning gasoline, resulting in a lower potential for forming the damaging ozone. In Canada, where the volatility of ethanol blends must match normal gasoline, the ozone forming potential of ethanol blends is even lower than in the U.S., where ethanol blends are allowed to have increased volatility.2

Reduction in Harmful Greenhouse Gases: The 'Greenhouse Effect' refers to the Earth's atmosphere trapping the sun's radiation. It is a term often used synonymously with 'Global Warming', which refers to the increasing average global temperature, arising from an increase in greenhouse gases from industrial activity and population growth. Greenhouse gases contributing to the Greenhouse Effect include carbon dioxide, methane, and nitrogen oxide.2

The term 'Climate Change' refers to a wide range of changes in weather patterns that result from global warming. A substantial increase in the Earth's average temperature could result in a change in agricultural patterns and melting of polar ice caps, raising sea levels and causing flooding of low-lying coastal areas.2

The use of ethanol-blended fuels such as E85 (85% ethanol and 15% gasoline) can reduce the net emissions of greenhouse gases by as much as 37.1%. Ethanol-blended fuel as E10 (10% ethanol and 90% gasoline) reduces greenhouse gases by up to 3.9%. By the year 2010, the reductions for E85 and E10 are projected to be 44.5% and 4.6%, respectively. This represents only a small percentage of the total greenhouse gas reduction required from the Kyoto Protocol. It is expected that once ethanol is made from cellulose, the greenhouse gas emissions reductions will further improve. Hemp produces four times as much cellulose per acre than trees.2

Reduction in Net Carbon Dioxide (CO2) Emissions: Use of 10% ethanol-blended fuels results in a 6-10% net reduction of CO2. The carbon dioxide released from ethanol production and use is less than that absorbed by the plants and soil organic matter used to produce ethanol. The carbon dioxide produced during ethanol production and gasoline combustion is extracted from the atmosphere by plants for starch and sugar formation during photosynthesis. It is assimilated by the crop in its roots, stalks and leaves, which usually return to the soil to maintain organic matter, or in the grain, the portion currently used to produce ethanol. Over time, the organic matter breaks down to CO2, but with the implementation of conservation measures, such as reduced tillage, the soil organic matter will build up. Therefore, by increasing its organic matter content, the soil acts as a significant sink for carbon dioxide.2

Volatile Organic Compounds (VOC's):Volatile organic compounds are highly reactive in the atmosphere, and are significant sources of ground-level ozone formation. Because ethanol oxygenates the fuel, there is approximately a 7% overall decrease in exhaust VOC's emitted from low-level ethanol-blended fuels relative to conventional fossil fuels. In high level blends, the potential for exhaust VOC reduction is 30% or more. 2

Sulphur Dioxide (SO2) and Particulates: As ethanol contains no sulphur, and because it promotes more complete fuel combustion, blending gasoline with ethanol would reduce any potential for these emissions and the adverse effects of sulphur. In diesel engines, where SO2 and particulates are of concern, the use of ethanol-blended diesel or neat ethanol shows a significant reduction in these emissions. 2