Data / Rankings / Median Air Quality Index (US EPA) / Counties in Mississippi

Counties in Mississippi by median Air Quality Index (US EPA)

Bolivar County had the highest median Air Quality Index (US EPA) of 20 counties in 1999, at 67. Coahoma County had the lowest, at 8. The median was 58. Source: the U.S. Environmental Protection Agency.

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Highest67Bolivar County
Lowest8Coahoma County
Median5820 counties

Map of counties, 1999

Adams County: 58 indexBolivar County: 67 indexCoahoma County: 8 indexDeSoto County: 48 indexForrest County: 64 indexHancock County: 46 indexHarrison County: 57 indexHinds County: 45 indexJackson County: 58 indexJones County: 66 indexLauderdale County: 61 indexLee County: 63 indexLowndes County: 64 indexMadison County: 49 indexPanola County: 36 indexRankin County: 63 indexScott County: 61 indexWarren County: 54 indexWashington County: 9 indexYalobusha County: 46 index
  • Under 46
  • 46 to 52
  • 52 to 59
  • 59 to 63
  • 63 and over
  • No data
index, 1999. Hatched areas have no value for this period. Source: EPA, EPA AirData annual AQI by county: median daily AQI. Boundaries: U.S. Census Bureau cartographic boundary files.

All counties, 1999

Bolivar County: 67 indexBolivar County67Jones County: 66 indexJones County66Forrest County: 64 indexForrest County64Lowndes County: 64 indexLowndes County64Lee County: 63 indexLee County63Rankin County: 63 indexRankin County63Lauderdale County: 61 indexLauderdale County61Scott County: 61 indexScott County61Adams County: 58 indexAdams County58Jackson County: 58 indexJackson County58Harrison County: 57 indexHarrison County57Warren County: 54 indexWarren County54Madison County: 49 indexMadison County49DeSoto County: 48 indexDeSoto County48Hancock County: 46 indexHancock County46Yalobusha County: 46 indexYalobusha County46Hinds County: 45 indexHinds County45Panola County: 36 indexPanola County36Washington County: 9 indexWashington County9Coahoma County: 8 indexCoahoma County8Bolivar County: 67 indexBolivar County67Jones County: 66 indexJones County66Forrest County: 64 indexForrest County64Lowndes County: 64 indexLowndes County64Lee County: 63 indexLee County63Rankin County: 63 indexRankin County63Lauderdale County: 61 indexLauderdale County61Scott County: 61 indexScott County61Adams County: 58 indexAdams County58Jackson County: 58 indexJackson County58Harrison County: 57 indexHarrison County57Warren County: 54 indexWarren County54Madison County: 49 indexMadison County49DeSoto County: 48 indexDeSoto County48Hancock County: 46 indexHancock County46Yalobusha County: 46 indexYalobusha County46Hinds County: 45 indexHinds County45Panola County: 36 indexPanola County36Washington County: 9 indexWashington County9Coahoma County: 8 indexCoahoma County8
index. Source: EPA, EPA AirData annual AQI by county: median daily AQI. Retrieved 2026-10-12.

Full ranking

RankCounties1999
index		Change on 1998
1Bolivar County67n/a
2Jones County66+46
3Forrest County64n/a
3Lowndes County64n/a
5Lee County63+13
5Rankin County63n/a
7Lauderdale County61+16
7Scott County61n/a
9Adams County58+9
9Jackson County58+14
11Harrison County57n/a
12Warren County54+12
13Madison County49+1
14DeSoto County48-1
15Hancock County46+2
15Yalobusha County46+2
17Hinds County45+11
18Panola County36-12
19Washington County9-9
20Coahoma County8-8

Other periods

About this ranking

Median of the daily Air Quality Index (AQI) values of a US county over the days of the year with an AQI, from the EPA AirData annual summaries.

More on how it is measured
  • The daily county AQI is the highest AQI among the monitors and pollutants reported that day (ozone, PM2.5, PM10, carbon monoxide and nitrogen dioxide).
  • Lower is cleaner: 0 to 50 is good, 51 to 100 moderate and above 100 unhealthy for sensitive groups.

United States counties with air quality monitors only, about 1,000 of some 3,100 in recent years; a county without monitors has no value. The number of days with an AQI differs between counties because some monitors run only in the ozone season.

Every value in the ranking comes from the same publisher and the same period, so the counties are compared on one definition. 9 counties with data in other periods have no value for 1999 and are left out rather than filled from another source. Equal values share a rank.

How to cite

U.S. Environmental Protection Agency, Air Quality System, AirData. EPA AirData annual AQI by county: median daily AQI. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Retrieved 2026-10-12.

Citation styles

The publisher is the author. Invokely is named only as the place the figures were read, where a style asks for it.

APA 7

U.S. Environmental Protection Agency. (2026). EPA AirData annual AQI by county: median daily AQI (Counties in Mississippi by median Air Quality Index (US EPA), 1999) [Data set]. Retrieved October 12, 2026, from https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual

MLA 9

EPA AirData annual AQI by county: median daily AQI, Counties in Mississippi by median Air Quality Index (US EPA), 1999. U.S. Environmental Protection Agency, 13 July 2026, https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Invokely, https://invokely.ai/rankings/median-air-quality-index/mississippi-counties?period=1999. Accessed 12 Oct. 2026.

Chicago (author-date)

U.S. Environmental Protection Agency. 2026. EPA AirData annual AQI by county: median daily AQI. Counties in Mississippi by median Air Quality Index (US EPA), 1999. Dataset. Accessed October 12, 2026. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Also distributed by Invokely, https://invokely.ai/rankings/median-air-quality-index/mississippi-counties?period=1999.

Harvard

U.S. Environmental Protection Agency (2026) EPA AirData annual AQI by county: median daily AQI, Counties in Mississippi by median Air Quality Index (US EPA), 1999 [Dataset]. Available at: https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual, via Invokely: https://invokely.ai/rankings/median-air-quality-index/mississippi-counties?period=1999 (Accessed: 12 October 2026).

BibTeX
@misc{environmental_counties_in_mississippi_by_1999,
  author = {{U.S. Environmental Protection Agency}},
  title = {{EPA AirData annual AQI by county: median daily AQI: Counties in Mississippi by median Air Quality Index (US EPA), 1999}},
  year = {2026},
  howpublished = {Data set},
  url = {https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual},
  urldate = {2026-10-12},
  note = {Accessed via Invokely, https://invokely.ai/rankings/median-air-quality-index/mississippi-counties?period=1999. Publisher attribution: U.S. Environmental Protection Agency, Air Quality System, AirData. EPA AirData annual AQI by county: median daily AQI. https://aqs.epa.gov/aqsweb/airdata/download\_files.html\#Annual. Retrieved 2026-10-12.},
}
RIS
TY  - DATA
AU  - U.S. Environmental Protection Agency
TI  - EPA AirData annual AQI by county: median daily AQI: Counties in Mississippi by median Air Quality Index (US EPA), 1999
PY  - 2026
DA  - 2026/07/13
PB  - U.S. Environmental Protection Agency
DB  - Invokely
UR  - https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual
L2  - https://invokely.ai/rankings/median-air-quality-index/mississippi-counties?period=1999
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/rankings/median-air-quality-index/mississippi-counties?period=1999.
N1  - Publisher attribution: U.S. Environmental Protection Agency, Air Quality System, AirData. EPA AirData annual AQI by county: median daily AQI. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Retrieved 2026-10-12.
ER  -
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Rank Counties in Mississippi by median Air Quality Index (US EPA) using official data, and cite the source.
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Questions

Which county has the highest median Air Quality Index (US EPA)?

Bolivar County, with 67 in 1999, according to the U.S. Environmental Protection Agency.

Which county has the lowest median Air Quality Index (US EPA)?

Coahoma County, with 8 in 1999.

Where does this ranking come from?

Every value comes from one source and one period, so the places are comparable: U.S. Environmental Protection Agency, EPA AirData annual AQI by county: median daily AQI. Retrieved 2026-10-12. 9 counties have no value for 1999 and are not ranked.

Median Air Quality Index (US EPA): other rankings

Counties in Mississippi: more rankings