Name | Symbol | Major Sources | Impact |
Greenhouse Gases |
Carbon dioxide | CO2 | Is produced by the combustion of fossil fuels in power plants, industrial facilities, cars, trucks, and boats. Burning biomass, like agricultural debris, can also release CO2. | The largest greenhouse gas by quantity. Rarely directly toxic, except in extremely high concentrations. |
Methane | CH4 | A major component of natural gas, methane is released from gas pipelines and facilities. It is also released some agricultural activities like rice production. | A greenhouse gas that is 25x stronger than carbon dioxide over a 100-year period. It can also contribute to ozone formation. |
Nitrous Oxide | N2O | This gas is produced primarily in agriculture- and particularly as a byproduct of fertilizer use. There are also some industrial processes that produce N20. | A greenhouse gas that is nearly 300 x stronger than carbon dioxide over a 100-year period. Rarely toxic in the environment, but can cause dizziness, nausea, and brain damage in high concentrations. (N2O is laughing gas.) |
Air Pollutants |
Ammonia | NH3 | A common component of fertilizer, and fertilizer manufacturing, that is also produced in other industrial processes. | An eye, ear, and lung irritant that may also cause organ damage in high concentrations. |
Black Carbon | BC | Black carbon is essentially a form of soot. It is produced in fossil fuel combustion and biomass burning. | As a small particle, BC can be a respiratory hazard. It also absorbs heat in the atmosphere and can contribute to warming. |
Carbon Monoxide | CO | The combustion of fossil fuels is the major source of carbon monoxide. | Carbon monoxide is a health hazard that can cause illness and even death in high quantities. Even when it is not present in high enough concentrations to be directly toxic, its presence can reflect the overall concentration of air pollution. |
Mercury | Hg | Burning fossil fuels, and particularly some kinds of coal, can released mercury. It is also released in some industrial processes. | A health hazard, and particularly a neurotoxin. |
Nitrogen Oxides | NOx | Combustion of fossil fuels in cars and powerplants. The production and use of fertilizer is also a source of NOx. | A health hazard that can cause respiratory problems. It can also contribute to the formation of acid rain and ozone. |
Non-methane volatile organic compounds | NMVOCs | Volatile organic compounds are a wide class of compounds that can readily evaporate. Gasoline fumes are an example of a volatile organic compounds. NMVOCs includes compounds like benzene, formaldehyde, and ethylene. Most of these compounds come from chemical processes, such as plastics manufacturing, though there are some agricultural sources - like pine tar. Methane, which is also a volatile organic compound is displayed elsewhere in this tool. | Many of these compounds can be toxic, and some are carcinogenic. For example, benzene, can cause anemia, low birth rates, and leukemia |
Organic carbon | OC | OC refers to particulate matter that contains carbon. The sources of OC could include fossil fuel combustion, industrial processes, or biomass burning. | Organic particles could enter a person's lungs and cause breathing problems. Some of these particles can be toxic. |
Particulate Matter - 10 microns | PM10 | PM10 is essentially soot. Technically speaking it is particles in the atmosphere that are 10 microns or smaller (one micron is 1/1000th of a millimeter). PM10 can come from combustion of fossil fuels, other industrial sources, automobiles, biomass burning, and dust from agricultural fields. | Particles can enter a person's lungs and cause breathing problems. Some particles are non-toxic but can lead to breathing problems when they clog lungs. Other particles can clog lunch and can be chemically toxic. |
Particulate Matter - 2.5 microns | PM2.5 | PM2.5 is essentially soot. Technically speaking it is particles in the atmosphere that are 2.5 microns or smaller (one micron is 1/1000th of a millimeter). PM2.5 can come from combustion of fossil fuels, other industrial sources, automobiles, biomass burning, and dust from agricultural fields. PM10 and PM2.5 often have similar sources, and they just differ in the sizes of the particles. | Particles can enter a person's lungs and cause breathing problems. Some particles are non-toxic but can lead to breathing problems when they clog lungs. Other particles can clog lunch and can be chemically toxic. |
Sulfur Dioxide | SO2 | Sulfur dioxide comes from the combustion of fossil fuels and industrial processes. While there can be natural sources of SO2, like volcanoes, they are not significant in Louisiana and Mississippi. | SO2 can cause respiratory problems in people and can cause acid rain in the environment. |