Air Quality Rankings by City 2026: Best & Worst Air Quality Cities in the US
147 US cities ranked from cleanest to most polluted using the latest EPA AirNow observations (November 2026). The city with the worst air quality right now is El Paso, TX (AQI 65, Moderate); the best air quality city is Billings, MT (AQI 7). Use the lists below to see which cities have the worst air quality, which have the best, and where your own city falls. Weighing two specific places? Do a head-to-head air quality comparison between cities to see which is cleaner today.
If your city ranks poorly, the air inside your home is the part you can control — size a purifier for your room with our free CADR calculator.
· Real-time AQI from EPA AirNow monitoring stations
Which US cities have the worst and best air quality right now?
As of November 14, 2026, El Paso, TX has the worst air quality of the 147 US cities we track (AQI 65, Moderate), and Billings, MT has the best (AQI 7, Good). 127 cities currently have Good air (AQI 0–50) and 0 have an AQI above 100.
- ✓Worst air quality city: El Paso, TX — AQI 65 (Moderate)
- ✓Best air quality city: Billings, MT — AQI 7 (Good)
- ✓127 of 147 cities are Good (0–50); 20 Moderate (51–100); 0 above 100
- ✓Rankings use the latest EPA AirNow AQI observation for each city — lower is cleaner
Frequently asked questions
What are the top 10 US cities with the best air quality?▾
The top 10 US cities with the best air quality right now (lowest EPA AirNow AQI, November 14, 2026): 1. Billings, MT (AQI 7); 2. Milwaukee, WI (AQI 8); 3. Santa Rosa, CA (AQI 10); 4. San Francisco, CA (AQI 12); 5. San Jose, CA (AQI 13); 6. Vancouver, WA (AQI 13); 7. Lincoln, NE (AQI 13); 8. Aurora, IL (AQI 14); 9. Macon, GA (AQI 15); 10. Lubbock, TX (AQI 16).
What are the top 10 worst air quality cities in the US today?▾
The 10 US cities with the worst air quality today (highest EPA AirNow AQI, November 14, 2026): 1. El Paso, TX (AQI 65); 2. Spokane, WA (AQI 60); 3. San Antonio, TX (AQI 60); 4. Indianapolis, IN (AQI 58); 5. Anchorage, AK (AQI 57); 6. St. Paul, MN (AQI 57); 7. Minneapolis, MN (AQI 57); 8. Des Moines, IA (AQI 56); 9. Kansas City, MO (AQI 56); 10. Fresno, CA (AQI 55).
Which state has the worst air quality?▾
Arizona has the worst air quality of the 51 states ranked: its 2 monitored metro areas had a median daily AQI of 78 (Moderate) in 2025, averaging 9 days at Unhealthy or worse; the worst metro was Phoenix-Mesa-Scottsdale, AZ (median 78). California (median 61) and New Mexico (61) rank next. Each state is scored on its EPA metro areas (CBSAs) that contain a city we track, using EPA's Air Quality System annual summary for 2025: the median of those areas' median daily AQIs, ties broken by the mean number of days at Unhealthy (AQI 151+) or worse — so this reflects metro-area monitors in the latest published year, not every monitor in the state.
Which state has the best air quality?▾
Alaska has the best air quality of the 51 states ranked, with a 2025 median daily AQI of 27 (Good) across its monitored metro area and 0 days at Unhealthy or worse. Hawaii (median 29) and South Dakota (36) follow. Each state is scored on its EPA metro areas (CBSAs) that contain a city we track, using EPA's Air Quality System annual summary for 2025: the median of those areas' median daily AQIs, ties broken by the mean number of days at Unhealthy (AQI 151+) or worse — so this reflects metro-area monitors in the latest published year, not every monitor in the state.
How many US cities have unhealthy air quality today?▾
0 of the 147 cities we track currently have an AQI above 100 (Unhealthy for Sensitive Groups or worse). 20 are in the Moderate range (51–100) and 127 have Good air (0–50), based on the latest EPA AirNow observations.
What AQI counts as poor air quality for a city?▾
On the EPA scale, 0–50 is Good and 51–100 is Moderate. A city ranks as having poor air quality once its AQI passes 100 — sensitive groups are affected at 101–150, everyone at 151–200, and readings above 200 are Very Unhealthy. Lower AQI always means cleaner air.
Which US region has the best air quality right now?▾
Right now the Mountain has the single cleanest reading: Billings, MT at AQI 7 (Good). The Best Air Quality by Region section below lists the lowest-AQI city in all six US regions.
How are these cities ranked from best to worst?▾
Each city is ranked by its most recent EPA AirNow Air Quality Index, from lowest (cleanest) to highest (most polluted). The AQI reflects the worst of five pollutants at that moment — usually ozone or PM2.5 — so the same 0–500 scale lets you compare any two of the 147 cities directly.
Cities With the Best Air Quality
Top 20 cleanest-air US cities right now
Cities With the Worst Air Quality
Top 20 most polluted US cities right now
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Best Air Quality by US Region Today
Lowest AQI city in each region right now — useful for regional comparisons and relocation research.
States Ranked by Air Quality (2025)
Arizona had the worst air quality of the 51 states ranked (median daily AQI 78, 9 days at Unhealthy or worse per metro area) and Alaska the best (median 27). Rank 1 is the most polluted.
Each state is scored on its EPA metro areas (CBSAs) that contain a city we track, using EPA's Air Quality System annual summary for 2025: the median of those areas' median daily AQIs, ties broken by the mean number of days at Unhealthy (AQI 151+) or worse — so this reflects metro-area monitors in the latest published year, not every monitor in the state.
| Rank | State | Metro areas (cities) | Median AQI | Unhealthy+ days | Worst metro |
|---|---|---|---|---|---|
| 1 | Arizona | 2 (4) | AQI 78 | 9 | Mesa · median 78 |
| 2 | California | 11 (13) | AQI 61 | 9 | Riverside · median 87 |
| 3 | New Mexico | 2 (2) | AQI 61 | 1.5 | Albuquerque · median 61 |
| 4 | Nevada | 2 (2) | AQI 61 | 0 | Las Vegas · median 61 |
| 5 | Utah | 1 (1) | AQI 57 | 1 | Salt Lake City · median 57 |
| 6 | Missouri | 2 (2) | AQI 56 | 3.5 | St. Louis · median 56 |
| 7 | Arkansas | 1 (1) | AQI 55 | 0 | Little Rock · median 55 |
| 8 | Indiana | 2 (2) | AQI 54 | 1 | Indianapolis · median 54 |
| 9 | Ohio | 6 (6) | AQI 54 | 0.7 | Cincinnati · median 56 |
| 10 | Louisiana | 2 (2) | AQI 54 | 0 | Baton Rouge · median 54 |
| 11 | Texas | 11 (12) | AQI 53 | 4.4 | El Paso · median 70 |
| 12 | Delaware | 1 (1) | AQI 53 | 2 | Wilmington · median 53 |
| 13 | Oklahoma | 2 (2) | AQI 52 | 1 | Oklahoma City · median 52 |
| 14 | Kentucky | 2 (2) | AQI 52 | 0.5 | Louisville · median 52 |
| 15 | Georgia | 4 (4) | AQI 52 | 0 | Atlanta · median 53 |
| 16 | Alabama | 2 (2) | AQI 52 | 0 | Birmingham · median 52 |
| 17 | Mississippi | 1 (1) | AQI 52 | 0 | Jackson · median 52 |
| 18 | Idaho | 1 (1) | AQI 51 | 0 | Boise · median 51 |
| 19 | Kansas | 1 (1) | AQI 50 | 1 | Wichita · median 50 |
| 20 | Colorado | 3 (4) | AQI 50 | 0 | Aurora · median 58 |
| 21 | Tennessee | 3 (3) | AQI 48 | 0.3 | Nashville · median 50 |
| 22 | Florida | 7 (10) | AQI 48 | 0.1 | Jacksonville · median 52 |
| 23 | Maryland | 1 (1) | AQI 48 | 0 | Baltimore · median 48 |
| 24 | Minnesota | 1 (2) | AQI 47 | 6 | Minneapolis · median 47 |
| 25 | District of Columbia | 1 (1) | AQI 47 | 2 | Washington · median 47 |
| 26 | Washington | 3 (4) | AQI 47 | 2 | Seattle · median 48 |
| 27 | South Carolina | 2 (2) | AQI 47 | 0 | Charleston · median 47 |
| 28 | Illinois | 4 (5) | AQI 45 | 2.3 | Aurora · median 56 |
| 29 | Wisconsin | 2 (2) | AQI 45 | 2 | Milwaukee · median 45 |
| 30 | Wyoming | 1 (1) | AQI 45 | 0 | Cheyenne · median 45 |
| 31 | Pennsylvania | 6 (6) | AQI 44 | 0.3 | Philadelphia · median 53 |
| 32 | Nebraska | 1 (1) | AQI 44 | 0 | Omaha · median 44 |
| 33 | Iowa | 1 (1) | AQI 44 | 0 | Des Moines · median 44 |
| 34 | North Carolina | 5 (5) | AQI 44 | 0 | Charlotte · median 52 |
| 35 | Connecticut | 2 (2) | AQI 43 | 2 | New Haven · median 43 |
| 36 | New Jersey | 3 (4) | AQI 43 | 1.3 | Jersey City · median 53 |
| 37 | Rhode Island | 1 (1) | AQI 43 | 1 | Providence · median 43 |
| 38 | Virginia | 2 (3) | AQI 43 | 0 | Richmond · median 43 |
| 39 | Michigan | 5 (5) | AQI 41 | 1.4 | Detroit · median 54 |
| 40 | New York | 5 (7) | AQI 41 | 0.8 | New York · median 53 |
| 41 | Oregon | 1 (1) | AQI 41 | 0 | Portland · median 41 |
| 42 | Maine | 1 (1) | AQI 40 | 1 | Portland · median 40 |
| 43 | Massachusetts | 3 (4) | AQI 40 | 0 | Boston · median 44 |
| 44 | West Virginia | 1 (1) | AQI 39 | 0 | Charleston · median 39 |
| 45 | Vermont | 1 (1) | AQI 38 | 1 | Burlington · median 38 |
| 46 | New Hampshire | 1 (1) | AQI 38 | 0 | Manchester · median 38 |
| 47 | Montana | 1 (1) | AQI 38 | 0 | Billings · median 38 |
| 48 | North Dakota | 1 (1) | AQI 37 | 7 | Fargo · median 37 |
| 49 | South Dakota | 1 (1) | AQI 36 | 0 | Sioux Falls · median 36 |
| 50 | Hawaii | 1 (1) | AQI 29 | 0 | Honolulu · median 29 |
| 51 | Alaska | 1 (1) | AQI 27 | 0 | Anchorage · median 27 |
Source: EPA Air Quality System, Annual AQI by CBSA, 2025. Each area’s daily AQI is the highest reading from any monitor in that area that day. “Unhealthy+ days” is the mean per metro area of days at AQI 151 or above. States with no tracked city in an EPA metro area are not listed.
About These Rankings
Rankings are based on the most recent Air Quality Index (AQI) observations from EPA monitoring stations via the AirNow network. The AQI is calculated from measurements of five major pollutants: ground-level ozone, particulate matter (PM2.5 and PM10), carbon monoxide, sulfur dioxide, and nitrogen dioxide. Lower AQI values indicate cleaner air. Rankings are rebuilt from a fresh AirNow pull each time the site is published.
How to Read These Air Quality Rankings
Every city in this list is ranked by its Air Quality Index (AQI) — a single 0–500 number the U.S. EPA uses to report how clean or polluted the air is right now and what it means for your health. A lower AQI is better: cities near the top of the “Best Air Quality” list have the cleanest air today, while those flagged as “requiring caution” have elevated pollution that can affect sensitive groups. Because the AQI is reported on the same scale nationwide, you can compare any two cities directly — an AQI of 35 in one city means the same thing as an AQI of 35 in another.
The headline AQI for each city reflects whichever pollutant is highest at the moment — usually ground-level ozone (worst on hot, sunny afternoons) or PM2.5 fine particles (worst during wildfire smoke and winter inversions). That’s why a city’s rank can shift hour to hour and season to season. Use the color-coded scale below to translate any AQI value into a plain-English health recommendation.
Air Quality Index (AQI) Scale Explained
| AQI | Category | What It Means for You |
|---|---|---|
| 0–50 | Good | Air quality is satisfactory, and air pollution poses little or no risk. |
| 51–100 | Moderate | Air quality is acceptable. However, there may be a risk for some people, particularly those who are unusually sensitive to air pollution. |
| 101–150 | Unhealthy for Sensitive Groups | Members of sensitive groups may experience health effects. The general public is less likely to be affected. |
| 151–200 | Unhealthy | Some members of the general public may experience health effects; members of sensitive groups may experience more serious health effects. |
| 201–300 | Very Unhealthy | Health alert: The risk of health effects is increased for everyone. |
| 301–500 | Hazardous | Health warning of emergency conditions: everyone is more likely to be affected. |
A “good” AQI is 0–50. Most people only need to take precautions once the AQI rises above 100 (Unhealthy for Sensitive Groups), while a reading above 150 means everyone should consider limiting strenuous outdoor activity. Scale and health categories follow the EPA AirNow standard.
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Browse Air Quality by State
Complete 2026 Air Quality Rankings
| Rank | City | State | AQI | Category |
|---|---|---|---|---|
| 1 | Billings | Montana | AQI 7 | Good |
| 2 | Milwaukee | Wisconsin | AQI 8 | Good |
| 3 | Santa Rosa | California | AQI 10 | Good |
| 4 | San Francisco | California | AQI 12 | Good |
| 5 | San Jose | California | AQI 13 | Good |
| 6 | Vancouver | Washington | AQI 13 | Good |
| 7 | Lincoln | Nebraska | AQI 13 | Good |
| 8 | Aurora | Illinois | AQI 14 | Good |
| 9 | Macon | Georgia | AQI 15 | Good |
| 10 | Lubbock | Texas | AQI 16 | Good |
| 11 | Chicago | Illinois | AQI 16 | Good |
| 12 | Lansing | Michigan | AQI 16 | Good |
| 13 | Columbia | South Carolina | AQI 16 | Good |
| 14 | Manchester | New Hampshire | AQI 17 | Good |
| 15 | Madison | Wisconsin | AQI 18 | Good |
| 16 | Long Beach | California | AQI 19 | Good |
| 17 | Yonkers | New York | AQI 19 | Good |
| 18 | White Plains | New York | AQI 19 | Good |
| 19 | Springfield | Illinois | AQI 19 | Good |
| 20 | Peoria | Illinois | AQI 19 | Good |
| 21 | Dayton | Ohio | AQI 19 | Good |
| 22 | Detroit | Michigan | AQI 19 | Good |
| 23 | Ann Arbor | Michigan | AQI 19 | Good |
| 24 | Atlantic City | New Jersey | AQI 19 | Good |
| 25 | Mesa | Arizona | AQI 19 | Good |
| 26 | Burlington | Vermont | AQI 19 | Good |
| 27 | Los Angeles | California | AQI 20 | Good |
| 28 | Trenton | New Jersey | AQI 20 | Good |
| 29 | New Haven | Connecticut | AQI 20 | Good |
| 30 | Buffalo | New York | AQI 21 | Good |
| 31 | Albany | New York | AQI 21 | Good |
| 32 | Erie | Pennsylvania | AQI 21 | Good |
| 33 | Columbus | Ohio | AQI 21 | Good |
| 34 | Cincinnati | Ohio | AQI 21 | Good |
| 35 | Tacoma | Washington | AQI 21 | Good |
| 36 | Scranton | Pennsylvania | AQI 22 | Good |
| 37 | Cleveland | Ohio | AQI 22 | Good |
| 38 | Akron | Ohio | AQI 22 | Good |
| 39 | Augusta | Georgia | AQI 22 | Good |
| 40 | Savannah | Georgia | AQI 22 | Good |
| 41 | Raleigh | North Carolina | AQI 22 | Good |
| 42 | Greensboro | North Carolina | AQI 22 | Good |
| 43 | Winston-Salem | North Carolina | AQI 22 | Good |
| 44 | Baltimore | Maryland | AQI 22 | Good |
| 45 | Fargo | North Dakota | AQI 22 | Good |
| 46 | Rockford | Illinois | AQI 23 | Good |
| 47 | Virginia Beach | Virginia | AQI 23 | Good |
| 48 | Norfolk | Virginia | AQI 23 | Good |
| 49 | Santa Fe | New Mexico | AQI 23 | Good |
| 50 | Amarillo | Texas | AQI 24 | Good |
| 51 | Toledo | Ohio | AQI 24 | Good |
| 52 | Durham | North Carolina | AQI 24 | Good |
| 53 | Worcester | Massachusetts | AQI 24 | Good |
| 54 | Boise | Idaho | AQI 24 | Good |
| 55 | Portland | Maine | AQI 24 | Good |
| 56 | Wilmington | Delaware | AQI 24 | Good |
| 57 | Sacramento | California | AQI 25 | Good |
| 58 | Riverside | California | AQI 25 | Good |
| 59 | Syracuse | New York | AQI 25 | Good |
| 60 | Harrisburg | Pennsylvania | AQI 25 | Good |
| 61 | Boston | Massachusetts | AQI 25 | Good |
| 62 | Cambridge | Massachusetts | AQI 25 | Good |
| 63 | Allentown | Pennsylvania | AQI 26 | Good |
| 64 | Seattle | Washington | AQI 26 | Good |
| 65 | Fort Wayne | Indiana | AQI 26 | Good |
| 66 | Birmingham | Alabama | AQI 26 | Good |
| 67 | New York | New York | AQI 27 | Good |
| 68 | Pittsburgh | Pennsylvania | AQI 27 | Good |
| 69 | Newark | New Jersey | AQI 27 | Good |
| 70 | Jersey City | New Jersey | AQI 27 | Good |
| 71 | Hartford | Connecticut | AQI 27 | Good |
| 72 | Charleston | South Carolina | AQI 27 | Good |
| 73 | Cheyenne | Wyoming | AQI 27 | Good |
| 74 | Stockton | California | AQI 28 | Good |
| 75 | Philadelphia | Pennsylvania | AQI 28 | Good |
| 76 | Flint | Michigan | AQI 28 | Good |
| 77 | Baton Rouge | Louisiana | AQI 28 | Good |
| 78 | Bakersfield | California | AQI 29 | Good |
| 79 | Oakland | California | AQI 29 | Good |
| 80 | Charlotte | North Carolina | AQI 29 | Good |
| 81 | Washington | District of Columbia | AQI 29 | Good |
| 82 | Springfield | Massachusetts | AQI 30 | Good |
| 83 | Portland | Oregon | AQI 30 | Good |
| 84 | Providence | Rhode Island | AQI 30 | Good |
| 85 | Irvine | California | AQI 31 | Good |
| 86 | Orlando | Florida | AQI 31 | Good |
| 87 | Memphis | Tennessee | AQI 31 | Good |
| 88 | Visalia | California | AQI 32 | Good |
| 89 | St. Petersburg | Florida | AQI 32 | Good |
| 90 | West Palm Beach | Florida | AQI 32 | Good |
| 91 | Salt Lake City | Utah | AQI 32 | Good |
| 92 | Pensacola | Florida | AQI 33 | Good |
| 93 | Tucson | Arizona | AQI 33 | Good |
| 94 | Knoxville | Tennessee | AQI 33 | Good |
| 95 | Richmond | Virginia | AQI 33 | Good |
| 96 | Jacksonville | Florida | AQI 34 | Good |
| 97 | Honolulu | Hawaii | AQI 34 | Good |
| 98 | Nashville | Tennessee | AQI 35 | Good |
| 99 | Lexington | Kentucky | AQI 36 | Good |
| 100 | Jackson | Mississippi | AQI 36 | Good |
| 101 | Laredo | Texas | AQI 37 | Good |
| 102 | Miami | Florida | AQI 37 | Good |
| 103 | Tampa | Florida | AQI 37 | Good |
| 104 | Modesto | California | AQI 38 | Good |
| 105 | Dallas | Texas | AQI 38 | Good |
| 106 | Fort Worth | Texas | AQI 38 | Good |
| 107 | McAllen | Texas | AQI 38 | Good |
| 108 | Brownsville | Texas | AQI 38 | Good |
| 109 | Charleston | West Virginia | AQI 38 | Good |
| 110 | Fort Lauderdale | Florida | AQI 39 | Good |
| 111 | Las Vegas | Nevada | AQI 39 | Good |
| 112 | St. Louis | Missouri | AQI 39 | Good |
| 113 | New Orleans | Louisiana | AQI 39 | Good |
| 114 | Oklahoma City | Oklahoma | AQI 39 | Good |
| 115 | San Diego | California | AQI 41 | Good |
| 116 | Tallahassee | Florida | AQI 41 | Good |
| 117 | Sarasota | Florida | AQI 42 | Good |
| 118 | Albuquerque | New Mexico | AQI 42 | Good |
| 119 | Corpus Christi | Texas | AQI 43 | Good |
| 120 | Louisville | Kentucky | AQI 45 | Good |
| 121 | Little Rock | Arkansas | AQI 45 | Good |
| 122 | Reno | Nevada | AQI 46 | Good |
| 123 | Wichita | Kansas | AQI 46 | Good |
| 124 | Houston | Texas | AQI 47 | Good |
| 125 | Sioux Falls | South Dakota | AQI 47 | Good |
| 126 | Atlanta | Georgia | AQI 48 | Good |
| 127 | Montgomery | Alabama | AQI 49 | Good |
| 128 | Grand Rapids | Michigan | AQI 51 | Moderate |
| 129 | Fort Collins | Colorado | AQI 51 | Moderate |
| 130 | Omaha | Nebraska | AQI 51 | Moderate |
| 131 | Austin | Texas | AQI 52 | Moderate |
| 132 | Denver | Colorado | AQI 52 | Moderate |
| 133 | Aurora | Colorado | AQI 52 | Moderate |
| 134 | Phoenix | Arizona | AQI 54 | Moderate |
| 135 | Scottsdale | Arizona | AQI 54 | Moderate |
| 136 | Colorado Springs | Colorado | AQI 54 | Moderate |
| 137 | Tulsa | Oklahoma | AQI 54 | Moderate |
| 138 | Fresno | California | AQI 55 | Moderate |
| 139 | Kansas City | Missouri | AQI 56 | Moderate |
| 140 | Des Moines | Iowa | AQI 56 | Moderate |
| 141 | Minneapolis | Minnesota | AQI 57 | Moderate |
| 142 | St. Paul | Minnesota | AQI 57 | Moderate |
| 143 | Anchorage | Alaska | AQI 57 | Moderate |
| 144 | Indianapolis | Indiana | AQI 58 | Moderate |
| 145 | San Antonio | Texas | AQI 60 | Moderate |
| 146 | Spokane | Washington | AQI 60 | Moderate |
| 147 | El Paso | Texas | AQI 65 | Moderate |
Frequently Asked Questions About Air Quality Rankings
Which US city has the best air quality?
Currently, Billings, MT has the best air quality in the United States with an AQI of 7 (Good). Rankings come from the latest EPA AirNow observations available when this page was published.
Which US city has the worst air quality today?
Currently, El Paso, TX has the highest pollution levels with an AQI of 65 (Moderate). Air quality can change significantly throughout the day and by season.
How often are these air quality rankings updated?
Rankings are rebuilt every time the site is published, using the latest observations EPA AirNow has for each city. We publish several times a month, so a ranking can be hours to a few days old — individual city pages show the exact observation time behind each number.
What is considered "good" air quality?
Air quality is considered "Good" when the AQI is between 0-50. At this level, air pollution poses little or no risk, and outdoor activities are safe for everyone including sensitive groups. Currently, 127 out of 147 cities have good air quality.
How many US cities do you track for air quality?
We track EPA AirNow air quality observations for 147 cities across the United States, covering all 50 states plus Washington D.C. Our data comes from EPA-certified monitoring stations that measure PM2.5, ozone, and other key pollutants.
Which states have the best air quality in the US?
By 2025 EPA AQS metro-area data, the five states with the lowest median daily AQI are Alaska (27), Hawaii (29), South Dakota (36), North Dakota (37), Montana (38). The full table in the States Ranked by Air Quality section above lists all 51; view our state-by-state air quality data for city detail.
Is it safe to move to a city with moderate air quality?
Cities with moderate air quality (AQI 51-100) are generally safe for most people. However, sensitive groups including those with asthma, respiratory conditions, or heart disease should monitor local conditions. Check our health guides for specific recommendations.
What causes cities to have poor air quality?
Poor air quality is typically caused by vehicle emissions, industrial pollution, wildfires, weather patterns (like temperature inversions), and geographic factors. Cities in valleys or near industrial areas often experience higher pollution levels. Learn more about air pollution causes and health effects.