PM2.5 stands for particulate matter 2.5 microns or smaller. These particles are 30 times thinner than a human hair and come from car exhaust, power plants, wildfires, and burning fuel. They are small enough to bypass your body's natural defenses and enter your bloodstream.

How does air pollution affect the body?

Air pollution affects virtually every organ in the body. PM2.5 particles enter your lungs, pass into your bloodstream, and travel to your heart, brain, kidneys, liver, and other organs. This causes chronic inflammation, increasing risks of heart disease, stroke, lung cancer, dementia, and many other conditions.

How many people are affected by air pollution?

99% of the global population breathes air that exceeds WHO safety guidelines. Air pollution kills approximately 8 million people every year—more than AIDS, malaria, and tuberculosis combined.

Portugal's Porto Air Pollution Report

Overview

Air Pollution in Porto

Porto faces significant air pollution challenges. 100% of districts exceed the WHO guideline for clean air. This is putting 1.8 million across 18 districts at risk.

The average PM2.5 over 2023 was 7.7µg/m³. That's 1.5 times the WHO guideline for clean air of 5µg/m³.

This is equivalent of everybody, including children, smoking about 128 cigarettes in a year.

Trends

Air Quality Trend

Annual PM2.5 levels from 2014 to 2023. The WHO guideline for safe air is 5 µg/m³.

Health Impact

Life Expectancy Impact

If Porto met the WHO guideline of 5 µg/m³, the average person would live 0.26 years longer.

That's 456K years of life stolen from 1.8 million people. Years of watching children grow up. Years of building a career. Years of quiet mornings and celebrations.

Lives cut short. Breathing kills.

Most Polluted

Districts with Highest Pollution

The top 10 most polluted districts in Porto. These areas face the greatest health burden from air pollution.

1.Maia
0.4 years lost
2.Matosinhos
0.3 years lost
3.Vila do Conde
0.3 years lost
4.Gondomar
0.3 years lost
5.Porto
0.3 years lost
6.Vila Nova de Gaia
0.3 years lost
7.Valongo
0.3 years lost
8.Póvoa de Varzim
0.3 years lost
9.Trofa
0.3 years lost
10.Santo Tirso
0.2 years lost

Exposure

Population Exposure by Pollution Level

Distribution of population across different PM2.5 pollution levels. The WHO guideline is 5 µg/m³—only populations below this threshold are breathing safe air.

< 5 µg/m³

5-10 µg/m³

100%

1.8M

10-15 µg/m³

15-25 µg/m³

25-35 µg/m³

> 35 µg/m³

Districts

All 18 Districts in Porto

Complete air quality data for every district in Porto, sorted by population.

District	Population	PM2.5 µg/m³	Years Lost
Vila Nova de Gaia	299K	8.2	0.3 years
Porto	227K	8.2	0.3 years
Matosinhos	168K	8.5	0.3 years
Gondomar	162K	8.3	0.3 years
Maia	134K	8.8	0.4 years
Valongo	94K	8.1	0.3 years
Paredes	83K	6.6	0.2 years
Vila do Conde	78K	8.3	0.3 years
Penafiel	69K	6.1	0.1 years
Santo Tirso	67K	6.9	0.2 years
Póvoa de Varzim	62K	8.1	0.3 years
Felgueiras	55K	5.5	0.1 years
Paços de Ferreira	55K	6.0	0.1 years
Amarante	51K	5.5	0.0 years
Marco de Canaveses	49K	5.9	0.1 years
Lousada	47K	5.8	0.1 years
Trofa	38K	8.0	0.3 years
Baião	17K	5.0	0.0 years

Showing 18 districts, sorted by population (largest first). PM2.5 values are for 2023. Years lost calculated against WHO guideline of 5 µg/m³.

Breathing in Porto is Injurious to Health.