4.2 Toxic Air Pollutants

In addition to the six criteria air pollutants listed above, the Clean Air Act also requires the regulation of 189 other hazardous chemicals known as the Toxic Air Pollutants (TAPs). These pollutants are suspected or known to cause cancer or other serious health effects when people are exposed to certain quantities or in frequent exposures or over long periods of time. Operators of firms that have received permits under the Clean Air Act must comply with state and federal regulations to limit releases of TAPs and report any releases above the permitted levels. The list of toxic chemicals released to the air by major industrial plants is compiled by the Environmental Protection Agency (EPA) into an annual inventory known as the Toxic Release Inventory (TRI). The TRI not only includes chemicals emitted to the air, but also to surface water and land through the storage, treatment, transfer or disposal of the chemicals. TRI data is available for all facilities in the program since 1987 and includes over 650 chemicals. However, not all firms that emit these toxic chemicals are required to report their annual discharges. Smaller companies with fewer than 10 employees or those that emit less than the established amount for each EPCRA Section 313 chemical on the TRI list are not included in the annual TRI report.

Louisiana industries released 49,184,501 pounds of toxic air pollution in 2014.

source: EPA Toxic Release Inventory

The Air Quality Index, or AQI, is a measure of actual levels of criteria pollutants in the air you breathe. It is measured on a scale ranging from 0-500. Lower scores mean better air quality and less pollution, while higher scores mean that there is more pollution in the air. The air quality scores are broken down into easy-to-understand color-coded categories. Green indicates that the air quality is good, and purple or maroon indicate that the air quality is unhealthy or hazardous to breathe. Sensitive groups include children, active adults (because they tend to breathe more during heavy activity), those with respiratory diseases like asthma, and the elderly.

Air Quality Index Levels of Health Concern Numerical
Good 0 to 50 Air quality is considered satisfactory, and air pollution poses little or no risk.
Moderate 51 to 100 Air quality is acceptable; however, for some pollutants there may be a moderate health concern for a very small number of people who are unusually sensitive to air pollution.
Unhealthy for Sensitive Groups 101 to 150 Members of sensitive groups may experience health effects. The general public is not likely to be affected.
Unhealthy 151 to 200 Everyone may begin to experience health effects; members of sensitive groups may experience more serious health effects.
Very Unhealthy 201 to 300 Health warnings of emergency conditions. The entire population is more likely to be affected.
Hazardous 301 to 500 Health alert: everyone may experience more serious health effects.

Note: Values above 500 are considered Beyond the AQI. Follow recommendations for the “Hazardous category.” Additional information on reducing exposure to extremely high levels of particle pollution is available here. Source: AirNow.gov

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4.1 Air Quality

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