Air Quality in Missouri

Missouri has 21 counties with EPA air quality monitoring. Air quality is stable across the state, with an average of 230 "Good" days per county per year. The best air quality is in Taney (median AQI 26) and the most polluted is St. Louis City (median AQI 54).

County	Median AQI	Max AQI	Good Days	Unhealthy Days	Trend	Top Pollutant
Andrew	43	100	223	0	→ stable	Ozone
Boone	39	77	244	0	→ stable	Ozone
Buchanan	44	77	216	0	→ stable	PM2.5
Callaway	40	77	249	0	→ stable	Ozone
Cass	42	107	278	1	→ stable	Ozone
Cedar	40	80	305	0	→ stable	Ozone
Clay	41	122	280	4	→ stable	Ozone
Clinton	41	101	219	1	→ stable	Ozone
Greene	45	90	227	0	→ stable	PM2.5
Jackson	46	109	213	1	→ stable	PM2.5
Jasper	41	99	289	0	↑ worsening	Ozone
Jefferson	40	105	292	1	→ stable	Ozone
Lincoln	42	143	222	2	→ stable	Ozone
Monroe	36	84	350	0	→ stable	Ozone
Perry	42	93	214	0	→ stable	Ozone
Saint Charles	44	129	191	3	→ stable	Ozone
Saint Louis	43	122	266	2	↓ improving	Ozone
Sainte Genevieve	43	100	225	0	→ stable	Ozone
St. Louis City	54	156	139	10	→ stable	PM2.5
Stoddard	29	71	99	0	→ stable	PM2.5
Taney	26	73	104	0	↓ improving	PM2.5