SmogRank / World / North America / Canada / New Brunswick

Most polluted cities in New Brunswick, Canada

5 measured cities, this year; 1 above the WHO annual guideline. Worst: Bathurst at 5.2 µg/m³, #2,560 in the world.

Ranked by unhealthy days: the share of each city's measured days with a daily mean over 35.4 µg/m³ (US AQI 101+), Unhealthy for Sensitive Groups or worse on the US EPA's scale. Ties go to the higher average.

Quebec: 16 measured citiesNew Brunswick: 5 measured citiesNova Scotia: 3 measured citiesPrince Edward Island: 1 measured city#5 Miramichi: 4.2 µg/m³#4 Moncton: 4.3 µg/m³#3 Fredericton: 4.4 µg/m³#2 Saint John East: 4.8 µg/m³#1 Bathurst: 5.2 µg/m³
Each dot is a measured city, coloured by its PM2.5; tap a dot to open the city.
← Bathurst 0% 0.75%0
Every measured city in New Brunswick, Canada, one column each, ranked by unhealthy days: height is the share of its measured days that were unhealthy, colour its average. Point at it to read a city; tap to open it.
  1. 1Bathurst 0%
  2. 2Saint John East 0%
  3. 3Fredericton 0%
  4. 4Moncton 0%
  5. 5Miramichilast full day 3 Oct 0%
Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales

Estimated: cities without a monitor

New Brunswick cities we can't measure, with model estimates for the last 7 days. Listed by population, not ranked: estimates aren't precise enough to rank. Model estimates from the Copernicus Atmosphere Monitoring Service (CAMS), adjusted to measured cities nearby where there are any. Adjusted, a single day lands within ×1.5 of what a monitor would read about two times in three; unadjusted, it can be off by half or double. Treat them as a guide, not a measurement.

City7-day estimateBand
Saint John≈ 6 µg/m³Good
Dieppe≈ 4 µg/m³Good
Riverview≈ 4 µg/m³Good
Quispamsis≈ 4 µg/m³Good
Edmundston≈ 3 µg/m³Good
Lutes Mountain≈ 4 µg/m³Good
Saint John West≈ 6 µg/m³Good

Bad-air episodes in New Brunswick

Times when many cities around here had PM2.5 at twice their usual or more on the same days.

Use this board

SmogRank, most polluted cities in New Brunswick, Canada, PM2.5, this year to 6 Oct 2026, 22:00 UTC, smogrank.com/ca/region/new-brunswick?w=year.

Download top 10 (PNG)

You're welcome to reuse a single chart, image or figure with this citation and a link. Terms. Raw monitor readings in bulk are published by OpenAQ, under each provider's licence.

Updated 2026-10-06 22:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the US AQI PM2.5 sub-index.